roots international No. 2, 2012

Cover / Editorial / Content / Cone-beam computed tomography in endodontics— Overcoming limitations / Diagnosis and management of a longitudinal fracture necrosis associated with an extensive periodontal defect / Dental occlusion/TMJ and general body health / Canal anatomy: The ultimate directive in instrument design and utilisation / WaveOne― First experiences of third-year students / Scouting the root canal with dedicated NiTi files / Infection control / Analysis of micro leakage using a self-etching adhesive system on casting and fiber glass posts / Industry News / “History & Heritage —Forging the Future” / International Events / Submission Guidelines / Imprint

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issn 2193-4673

roots
international magazine of

Vol. 8 • Issue 2/2012

endodontology

2

2012

| case report
Cone-beam computed tomography
in endodontics—Overcoming limitations

| opinion
WaveOne―First experiences
of third-year students

| industry report
Analysis of micro leakage using
a self-etching adhesive system
on casting and fiber glass posts

[2] => RO0110_01_Titel

Distributed by

crosslinked gutta-percha core obturator

Gutta-percha

Crosslinked gutta-percha core

• superior 3D fills
• ease of retreatment
• post space simplified

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[3] => RO0110_01_Titel

editorial _ roots

I

Dear Reader,
_Vince Lombardi so eloquently stated, “Practice does not make perfect. Only perfect practice makes
perfect.” In other words, we can perform a procedure repeatedly yet not obtain the expected outcome for
success. We must continually advance in all disciplines of dentistry in order to provide our patients with the
most predictable treatment regimens possible, understanding that the greatest variable that stands in our
way is the human variable. Elevating the standards of endodontic care is inexorably tied to an important
dynamic, our armamentaria.1 The objective of endodontic treatment has remained a constant since rootcanal treatment was first performed: the prevention and/or treatment of apical periodontitis such that there
is complete healing and an absence of infection.2 The most important advancements in clinical endodontics
forever changed the endodontic landscape with the emergence and development of four technologies.3, 4

Dr Gary Glassman

The dental operating microscope, not only provides us superior vision to diagnose cracks and track
vertical fractures3,5, but also to locate anatomy and then subsequently address that anatomy. Sonic and
ultrasonic instruments have allowed us to be able to carry out refinement of access openings, locate
calcified canals in a controlled and predictable manner, and eliminate the smear layer, and biofilm that
has remained in the canal after instrumentation.3, 6, 7 NiTi files have allowed more predictable canal
shapes,3 in reduced time compared to stainless-steel files, while maintaining the original canal anatomy
and producing less extrusion of debris.8, 9 Mineral trioxide aggregate is a remarkable and biocompatible
restorative material that has become the standard for pulp capping and root perforation, and has salvaged
countless teeth that previously had been considered hopeless. Perhaps the greatest international attention in recent years has focused on methods to improve endodontic disinfection in the root-canal system.3
Files shape; irrigants clean. We rely on our irrigants and irrigant delivery systems to penetrate into the
complex anatomy that our instruments cannot shape, in order to eliminate the organic tissue and bacterial inoculum that exists within. The early works of Hess suggest this is ongoing to be challenging by virtue
of it complexity.10
As I fly 32,000 feet over the Pacific Ocean after lecturing and running Essential Endo Clinical Skill set
programmes in both Europe and Asia, it boggles my mind how, with all the modern technologies that exist
today to provide predictable endodontics, the fundamentals are often ignored: Vision, tooth isolation and
irrigation. An overwhelming number of general dentists and, surprisingly, endodontists worldwide do not
use rubber dams and provide endodontic treatment through a matte of caries. Saliva is allowed to slop into
the pulp chamber like the pungent backwater of a contaminated estuary. This is analogous to providing
state-of-the-art building technology with the finest of materials but constructing the foundation on a bogland. To take short-cuts during treatment to reduce costs, and to justify it to oneself, is to retreat into a
mindset of persistent cognitive dissonance. In order to achieve endodontic nirvana and enjoy the successes
that the recent technologies allow us to achieve, we must get back to fundamentals and provide grass roots
education in a stepwise, systematic manner to those who will be providing the treatment.“
“Science and research will elevate the specialty of endodontics to its rightful pinnacle.”11 “The
cornerstone to our specialty’s integrity and relevance must be built on a strong foundation of randomised clinical trials and evidenced-based endodontics.”11 The future of endodontics is bright and
holds incredible promise as we continue to develop new techniques and technologies that will allow us
to perform endodontic treatment painlessly and predictably, and continue to satisfy one of the main
objectives in dentistry, that being to retain the natural dentition.12

Dr Gary Glassman
Doctor of Dental Surgery
Fellow of Royal College of Dentists of Canada

Editorial note: A complete list of
references is available from the
publisher.

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[4] => RO0110_01_Titel

I content _ roots

page 6

I editorial
03

page 8

page 16

I industry report

Dear Reader

30

| Dr Gary Glassman

Analysis of micro leakage using a self-etching adhesive
system on casting and fiber glass posts
| Prof Alejandro Paz et al.

I case report
06

Cone-beam computed tomography in endodontics—
Overcoming limitations

I industry news
34

| Dr Shanon Patel

08

| VDW

Diagnosis and management of a longitudinal fracture
necrosis associated with an extensive periodontal defect

34

| Dr Antonis Chaniotis

36

20

Dental occlusion/TMJ and general body health

I meetings

| Dr Yong-Keun Lee et al.

38

“History & Heritage—Forging the Future”
AAE holds its annual session in Boston
| Fred Michmershuizen

Canal anatomy: The ultimate directive in instrument
design and utilisation

40

| Dr Barry L. Musikant

I about the publisher

WaveOne―First experiences of third-year students
| Prof Michael A. Baumann

24

Moisture-activated temporary filling and sealing material
| Centrix

I opinion
16

Everything you like about X-Smart—with a Plus
| DENTSPLY

I reviews
12

RECIPROC wins innovation prize 2011

41
42

International Events

| submission guidelines
| imprint

Scouting the root canal with dedicated NiTi files
| Dr Gilberto Debelian et al.

I special
28

Infection control

Cover image courtesy of Produits Dentaires SA
(www.pdsa.ch)

| Dr Frank Y. W. Yung

page 20

04 I roots
2_ 2012

page 24

page 38

[5] => RO0110_01_Titel

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[6] => RO0110_01_Titel

I case report _ CBCT in endodontics

Cone-beam computed
tomography in endodontics—
Overcoming limitations
Author_ Dr Shanon Patel, UK

Fig. 1_The Accuitomo CBCT scanner
(Morita) housed in a purpose-built
acquisition room; the radiographer
sits on the other side of the room,
allowing her to programme the
scanner.

Fig. 1

_Introduction
Fig. 2_A periapical radiograph of
the upper left quadrant does not
show any signs of apical pathology.
Note that the zygomatic buttress is
obscuring the apices of teeth #26
and 27. Tooth #25 had been root
treated to an acceptable standard.

Irreversible pulpitis can often be challenging to
diagnose and therefore frustrating to manage. Often
patients will complain of poorly localised pain on one
side of their face; they may be unable to localise even
the quadrant from which the symptoms originate.
Clinical examination may be unremarkable, no obvious signs may be elicited, and the results of vitality
testing may be inconclusive.

In these situations, it is not uncommon for conventional radiographs (film or digital sensors), taken
at several different views of the area of interest,
not to reveal anything untoward. This is because conventional radiographs have several limitations. The
image is the result of the complex (3-D) anatomy
being radiographed being compressed into a 2-D
“shadowgraph”; this inevitably results in loss of potentially useful information (for example, the axial
plane that is not usually seen with radiographs ). The
images produced with radiographs, even when taken
with a beam-aiming device, have a certain degree of
geometric distortion, as it is often impossible to place
the image receptor parallel to the long axis of the
tooth. Finally, the anatomy overlying the area of interest (for example, zygomatic buttress, cortical bone)
often masks the area of interest—this phenomenon is
known as anatomical noise.
CBCT may be used to overcome the limitations of
conventional radiographs. CBCT is an imaging system
that has been specifically designed to produce 3-D
images of the maxillo-facial skeleton (Fig. 1). These
images are produced quickly and effortlessly, and
assessed using relatively simple software on standard
PCs.
Having access to CBCT imaging is a tremendous
benefit in specialist endodontic practice. Most importantly, using a small field of view, the effective dose to
the patient can be kept to a minimum.
The case described in this article demonstrates
how CBCT may be used to manage a common diagnostic problem more effectively.

_Case report
A 45-year-old fit and healthy female patient was
referred by her GDP for management of her pain,
localised to the left side of her face. On presentation,

Fig. 2

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[7] => RO0110_01_Titel

case report _ CBCT in endodontics

Figs. 3a & b_Reconstructed
sagittal (a) and axial (b) slices clearly
show the presence of a periapical
radiolucency (yellow arrow), and
three canals.

Fig. 3a

Fig. 3b

the patient complained of poorly localised pain over
the left side of her maxilla. The pain was spontaneous,
woke her up at night, and was dull and throbbing in
character. These symptoms had been present for five
days and were steadily deteriorating.

be carried out until a definitive diagnosis has been
made. In this case, a periapical radiolucency was
readily detected with CBCT.

She had seen her dentist when the symptoms first
developed. He examined her and diagnosed tooth #25
as the cause of her symptoms and with her consent
root treated this tooth. Unfortunately, the symptoms
did not improve after this treatment.
Clinical examination revealed that the upper
and lower left quadrants were heavily restored; however, none of these teeth was tender to percussion
or palpation. None of the teeth was mobile and all
responded positively to vitality testing.
Conventional radiographs did not reveal anything
untoward: tooth #25 had undergone a well-executed
root-canal treatment, and no periapical radiolucencies could be detected (Fig. 2). A small-volume CBCT
scan was taken of the upper left quadrant. Reconstructed sagittal images clearly showed a periapical
radiolucency associated with the distobuccal root of
tooth #26, and the axial slices revealed the presence
of three canals (mesiobuccal, distobuccal and palatal;
Figs. 3a & b).

Perhaps not surprisingly, this same apical pathology could not be detected with conventional radiography, as the cortical plate and zygomatic buttress
masked the pathological changes occurring in the
cancellous bone. This case highlights the difficulties
that even experienced endodontists commonly face
in everyday practice, and demonstrates how CBCT
may be used to help make an accurate diagnosis.
The reconstructed axial slices were also useful
during examination. They confirmed the number and
exact position of the root-canal entrances before
treatment was commenced. This resulted in a conservative access-cavity preparation and swift identification of the root-canal entrances, thus allowing
treatment to be carried out effectively and efficiently._

Fig. 4_Completed root-canal
treatment.

_author

roots

Dr Shanon Patel
(BDS, MSc, M.Clin.Dent.,
MFDS Royal College of
Surgeons, MRD Royal
College of Surgeons)
Specialist endodontist

A diagnosis of chronic periapical periodontitis was
made for this tooth, and with the patient’s consent
this tooth was root treated in a single visit under local
anaesthetic (Fig. 4). The patient was contacted the
following day and reported that she was completely
asymptomatic.

_Discussion
The key to effective management is accurate diagnosis. Invasive (and irreversible) treatment should not

Fig. 4

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[8] => RO0110_01_Titel

I case report _ fracture diagnostic and management

Diagnosis and management
of a longitudinal fracture
necrosis associated with an
extensive periodontal defect
Author_ Dr Antonis Chaniotis, Greece

Fig. 1a

_Introduction
The terminology and classification of incomplete tooth fractures have received significant
attention in the scientific literature for many decades. Numerous terms and definitions have
been proposed through the years,
arising from the difficulties related to diagnosis,
prognosis assessment and treatment planning. Cuspal fracture (Gibbs 1954), fissure fracture (Thoma
1954), fissural fracture (Down 1957), crack lines and
greenstick fracture (Sutton 1961; 1962), cracked
tooth syndrome (Cameron 1964), hairline fracture
(Wiebusch 1972), split-root syndrome (Silvestri 1976),
enamel infraction (Andreasen 1981), crack lines and
craze lines (Abou-Rass 1983), and incomplete tooth

Fig. 1b

08 I roots
2_ 2012

fracture (Luebke 1984) are some of the terms used
through the years. Many of these terms were used
by different authors to describe the same clinical
entity.
Recently, the American Association of Endodontists categorised longitudinal tooth fractures into five
major classes:
_craze line;
_fractured cusp;
_cracked tooth;
_split tooth; and
_vertical root fracture (VRF).
Craze lines affect only the enamel, originate on the
occlusal surface, are typically from occlusal forces or
thermo-cycling, and are asymptomatic.

[9] => RO0110_01_Titel

case report _ fracture diagnostic and management

Fig. 1c

Fig. 1d

A fractured cusp is defined as a complete or
incomplete fracture initiated from the crown of the
tooth and extending sub-gingivally, usually directed
both mesiodistally and buccolingually.

these types of cracks is poor, with a high potential
for unfavourable post-treatment sequelae. In their
paper, Berman and Kuttler (2010) conclude that pulp
necrosis, in the absence of extensive restorations,
caries or luxation injuries, is likely caused by a longitudinal fracture extending from the occlusal surface
and into the pulp. They suggest, based on the available
literature, that these types of teeth may have a poor
prognosis after endodontic treatment, with the potential ramification of extensive periodontal and/or
periapical bone loss. They therefore suggest extraction as the primary treatment option.

A cracked tooth is defined as an incomplete
fracture initiated from the crown and extending subgingivally, usually directed mesiodistally.
A split tooth is defined as a complete fracture
initiated from the crown and extending sub-gingivally, usually directed mesiodistally through both of
the marginal ridges and the proximal surfaces.
A true VRF is defined as a complete or incomplete
fracture from the root at any level, usually directed
buccolingually.

Although this conclusion appears reasonable
enough, it should be noted that the detection of the
incomplete fracture line limits before proceeding to
the extraction of a longitudinally fractured tooth is of
outmost importance.

Cracked teeth are thought to occur as a result of
para-functional habits or weakened tooth structure.
The fractures are incomplete, tend to present in a
mesial-to-distal orientation, and are generally centred on the occlusal table. The symptoms that develop subsequent to these cracks have been termed
“cracked tooth syndrome”. This has been described
as acute pain that results during the mastication (or
release) of small, hard food substances and is exacerbated by cold. However, the signs and symptoms
of a cracked tooth may also be consistent with an
irreversible pulpitis or necrosis.

The detection of incomplete longitudinal fractures is a challenging task that is very often neglected. Generally, a combination of simple inspection,
transillumination, staining with dyes, diagnostic
surgery, microscopy and a cone-beam computerised
tomography scan is necessary to identify and confirm the presence of cracks. The extraction of cracked
teeth without identifying and documenting the
fracture line limits is unjustifiable according to the
author.

Based on the available literature and investigations on root cracks and fractures, it has been suggested that the endodontic prognosis for teeth with

The aim of the present case report is to demonstrate the importance of the diagnostic procedures
in the prognosis and treatment planning of incompletely longitudinally fractured teeth.

Fig. 1e

Fig. 1f

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[10] => RO0110_01_Titel

I case report _ fracture diagnostic and management
After administrating infiltration anaesthetic, a
rubber dam was placed. The temporary filling material was removed and the underlying dentine
was stained with methylene blue dye (Figs. 1b & c).
A fracture line was detected, extending from the
mesial marginal ridge across the dentinal structure
to the distal marginal ridge (Figs. 1c & d). The pulp
chamber was accessed in order to determine the
extent of the fracture line. Upon accessing the pulp
chamber, the pulp floor calcifications were removed
with ultrasonics under the microscope (Fig. 1e). The
pulp floor and the axial dentinal walls were stained
again with methylene blue dye and inspected under
the microscope (Fig. 1f). No fracture lines or cracks
were detected across the pulp floor, while the mesial
and the distal fracture line appeared to end before
entering the mesiobuccal and the distal root-canal
orifices.

Fig. 1g

_Case report
A 30-year-old male patient was referred to our endodontics practice for the evaluation and possible
treatment of his mandibular left first molar. The referral note mentioned a possible diagnosis of VRF and
suggested the extraction of the tooth, followed by
grafting and implant placement. The patient’s medical history was non-contributory. There was no history of trauma and no para-functional habits were
identified. There was a buccal swelling in the furcation
area and the tooth was percussion sensitive. The referring dentist had removed the amalgam restoration
and placed a temporary filling material. Cold and electric vitality tests were negative. There was a deep buccal periodontal probing defect. The clinical view of the
mandibular left first molar can be seen in Figure 1a.
The radiographic examination revealed an extensive
periapical lesion extending through the furcation
area (Fig. 2a).
The clinical and radiographic image indicated an
incomplete longitudinal fracture necrosis with an
associated extensive endodontic-periodontal defect.
A decision was made to seek to identify the fracture
line in order to assess the restorability of the tooth.

Fig. 1h

Fig. 1i

10 I roots
2_ 2012

The fractured tooth was judged as treatable and
restorable. Standard non-surgical root-canal treatment was accomplished under the microscope and
the tooth was restored using a dual-cured composite
resin build-up.
Shaping of the canals was accomplished using
the HyFlex CM rotary files (Coltène/Whaledent) and
cleaning of the canals was achieved according to
a strict irrigation protocol. The irrigation protocol
followed entailed syringe irrigation with a 6%
NaOCl solution with surface modifiers (CanalPro,
Coltène/Whaledent). The irrigation solution was activated with a #15 ultrasonic K-file (SATELEC) after
the completion of the shaping procedures (3 x 20
seconds per canal). The canals were dried with paper
points and flooded for five minutes with a 17% EDTA
solution (CanalPro). The final rinse was achieved
using sterile water. The canals were dried again and
were flooded for another five minutes with a 2%
chlorhexidine solution (Vista Dental). The canals
were rinsed again with sterile water and were dried
with sterile paper points (Roeko Cellpack, Coltène/
Whaledent).

[11] => RO0110_01_Titel

case report _ fracture diagnostic and management

Fig. 2a

Fig. 2b

Fig. 2c

Fig. 2d

The obturation of the canals was achieved using
the continuous wave of condensation technique plus
injectable thermo-plasticised gutta-percha backfilling.

According to the author, the operating microscope
is an indispensable aid for the detailed assessment
and documentation of incomplete fractures. A combination of microscopic inspection, transillumination,
staining with dyes and diagnostic surgery is what it
takes to identify incomplete fractures properly.

The pulp floor chamber was cleaned through
sodium bicarbonate sand-blasting (Fig. 1g) and the
orifices were covered with flowable dual-cured composite resin under the microscope. The build-up was
accomplished using dual-cured composite resin and
the occlusion was adjusted. The radiographic image of
the tooth after the completion of the root-canal treatment and the build-up can be seen in Figures 2b and c.
The tooth was monitored for one year. The oneyear follow-up radiograph revealed uneventful healing (Fig. 2d). The periodontal probing was within normal limits all around the tooth and the clinical view
was favourable (Figs. 1h & i).
The patient was referred back to his prosthodontist
for full-coverage crown protection. The prognosis of
this case was judged as excellent.

_Discussion
The diagnosis, prognosis assessment and treatment planning of cases with incomplete longitudinal
fractures can be really challenging. These fractures are
very difficult, if not impossible, to identify in the 2-D
periapical radiograph. The 3-D small field of view CBCT
scan provides far more information. However, even
with the CBCT scan, the incomplete fractures might
remain undetectable. The clinical identification of the
fracture lines and their extent throughout the tooth
structure is generally a difficult task.

The treatment planning of cases with incomplete
fractures should not rely on hypothesis, but should
always rely on microscopic diagnosis and documentation. Not every single case of a cracked tooth needs
extraction. The extraction of incompletely fractured
teeth without assessing and documenting the extent
of the fracture line is unjustifiable._

roots

_about the author

Dr Antonis Chaniotis graduated from the University of
Athens Dental School (Greece) in 1998. In 2003, he completed
the three-year postgraduate programme in Endodontics at
the dental school. He is a clinical instructor affiliated with the
undergraduate and postgraduate programmes in the Endodontics department at the dental school. He has worked in a
private practice in Athens limited to microscopic endodontics
since 2003.
He has published articles in local and international journals and he has lectured at
over 40 local and international congresses. In 2010, he joined the Roots Forum and
became well known for his clinical skills through his microscope-enhanced endodontic video case-management series. He has served as the administrator of the EndoImplant-Algorithm video blog of the Dental Tribune Study Club since January 2011.
Dr Antonis Chaniotis can be contacted via his e-mail address at antch@otenet.gr
or through his website, www.endotreatment.gr

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[12] => RO0110_01_Titel

I review _ dental occlusion/TMJ

Dental occlusion/TMJ
and general body health
Clinical evidence and mechanism of an
underestimated relationship
Author_ Dr Yong-Keun Lee & Dr Hyung-Joo Moon, South Korea

_During the treatment of symptoms originating
from disorders of the temporomandibular joint (TMJ)
and occlusion, it was found that restoring the TMJ to
its normal condition resulted in a change of general
body health. In most cases, this change was improved
general body health. Owing to similar reports, a connection between TMJ status and general body health
was therefore hypothesised. However, the mechanism
of this relationship remains unclear.
In this article, the relationships between dental
occlusion/TMJ status and general body health are
reviewed with reference to peer-reviewed papers. A
conceptual theory is proposed that may explain this
mechanism.

_TMJ and myofascial pain
Dental occlusion is the relationship between the
maxillary and mandibular teeth when they approach
each other.1 The TMJ is the joint of the jaw, which
is unique in that it is the only bilateral joint that
crosses the midline.2 As the treatment of dental diseases aims to achieve harmony within the entire
stomatognathic system, teeth could be literally considered to be a set of gears anchored in bone, while
the upper and lower jaws are attached to each other
by the TMJ.3
The causes of TMJ disorders can be divided into five
categories: dental, trauma, lifestyle habits, stressful
social situations and emotional factors.4 Trauma can
be in the form of whiplash, traction appliances and
blows to the head, face or jaw.4 Evidence of significant
trauma to the TMJ has also been found following
hyperextension of the cervical spine.5 With regard to
habits, bad posture, bad ergonomics at work, oral and

12 I roots
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[13] => RO0110_01_Titel

FDI World Dental Federation
Leading the World to Optimal Oral Health

2012 Hong Kong
FDI Annual World Dental Congress
29 August - 1 September 2012

1. Celebrate the uniqueness of FDI at its
100th Annual World Dental Congress;

6. Enjoy exclusive face-to-face encounters
with your peers worldwide;

2. Learn about the latest developments
from international and regional experts;

7. Develop your knowledge and skills
through a new and innovative programme;
8. Sample some of the best cuisine
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inhabitants!

3. Discover the newest technology,
equipment, products and materials;
4. Interact with renowned world
specialists;
5. Empower yourself through FDI
sessions on policy and public and oral
health;

9. Marvel at the breathtaking views of
Hong Kong and Macau;
10. Uncover the riches and mysteries of
mainland China.

Leading the world into a new century of oral health

www.fdicongress.org

congress@fdiworldental.org

Design: b’com · +33 (0)6 50 46 60 70

10 reasons to join FDI in Hong Kong,
World Oral Health Capital 2012

[14] => RO0110_01_Titel

I review _ dental occlusion/TMJ
childhood habits, as well as poor diet and strenuous
activities such as heavy lifting, have been cited.4
Myofascial pain, deriving from the hyperalgesic
trigger points located in skeletal muscle and fascia, is
commonly characterised by persistent regional pain.6
The myofascial component has generally been considered to be part of pain syndromes that involve TMJ.
Trigger points in masticatory muscles are presumably
caused by malocclusion, misalignment and habitual
para-function of the jaws, abnormal head and neck
postures, or trauma.6

The biomechanical impact on cervical vertebrae
during mastication has been calculated, which confirmed that vertical occlusal alteration can influence
stress distribution in the cervical column.15 Possible
associations between trunk and cervical asymmetry
and facial symmetry have been reported.16 For example, it has been found that visual perception control is
most important in orienting the head in the frontal
plane.16 A relationship between dental occlusion and
postural control has also been postulated.17
TMJ and body stability

_Relationship between TMJ and general
Dental occlusion/TMJ condition exerts an influbody health
ence on body stability. Human beings assume a relaThere have been several studies on the relationship
between occlusion/TMJ and general body health.
Among other findings, it has been found that lesions
in the masticatory muscles or dento-alveolar ligaments can perturb visual stability and thus generate
postural imbalance.7 The position and functioning of
the mandible also have an effect on the centre of
gravity.8,9

“...lesions in the
masticatory muscles
or dento-alveolar
ligaments can perturb
visual stability.”
Dental occlusion is associated with reduced lower
extremity strength, agility and balance in elderly people.10 The proper functional occlusion of natural or
artificial teeth has been shown to play an important
role in generating an adequate postural reflex.11 The
subgroups of general body conditions associated
with TMJ may be divided into the following three
categories:
Synchronisation of the head and jaw muscles with
other muscles
There is a necessary systematic synchronisation of
the head and jaw muscles with the other muscles of
the body to maintain proper body posture. The functional coupling of the stomatognathic system with
the neck muscles is well known. Patients suffering
from occlusal or TMJ disorders have frequently reported dysfunction and pain in their neck muscles.12,13
An imbalance of sternocleidomastoid muscle activity,
often leading to neck pain, can be induced by a unilateral loss of occlusal support.14

14 I roots
2_ 2012

tively unstable postural state when in the standing
position; therefore, the maintenance of a standing
position is related to fluctuation in the centre of
gravity, which is controlled by information from the
ocular region, the three semicircular canals and antigravity muscles.18
It has been suggested that occlusion and head
position affect the centre of gravity, resulting in an
increased risk of falling when abnormal.19 Poor or
absent dental occlusion may decrease proprioception
in this area, interfering with the proper stability of the
head posture.7 It is thought that tooth loss is a risk factor for postural instability.20 Physiologically, mechanical receptors in the periodontal membrane control
mandibular movements and coordinate masticatory
function,21 and this is related to the motor activity of
the neck muscles.22
Fluctuation in the centre of gravity caused by
altering the occlusal contact area experimentally was
examined experimentally, and the results confirmed
that occlusal contact affects gravity fluctuation and
that appropriate occlusion attained by maintaining
even occlusal contact in the posterior region is crucial
for gravity fluctuation.23
TMJ and physical performance
TMJ conditions can influence physical performance. Trainers often advise athletes to wear occlusal
splints or mouth guards during competitions in order
to increase motor performance.24 It has also been reported that proper teeth clenching plays an effective
role in the enhancement of physical performance.25
The relationship between the presence of occlusal
support in edentulous subjects and their capacity for
physical exercise has been investigated, and it was
concluded that reconstruction of occlusal support
holds significance not only for the restoration of
masticatory function but also for the maintenance
of physical exercise.26

[15] => RO0110_01_Titel

review _ dental occlusion/TMJ

I

_Mechanism of relationship between the _Correlation between trigger points and
TMJ and general body health based on acupuncture points
the myofascial aspect
It is the first hypothesis of this article that TMJ
and other parts of the body are connected through fasciae, which is a connective element between various
anatomical structures,27 very similar to a three-dimensional network extending throughout the whole
body.28,29 This network can be stretched by the contraction of underlying muscles and transmit tension over
a distance.30,31
The fascial tissues are arranged vertically, from head
to toe, and four interconnected transverse fascial
planes criss-cross the body. Therefore, should an injury
occur in one part of the body, pain and dysfunction may
occur throughout the body.32

_Mechanism based on qi and the meridian
aspect
The second hypothesis is that the TMJ and other
parts of the body are connected through the meridian
system, which is constituted of the fasciae. Traditionally, acupuncture meridians are believed to form a
network throughout the body, connecting peripheral
tissues to each other.33 Studies that seek to understand the acupuncture point/meridian systems from
a Western perspective have mainly focused on identifying distinct histological features that differentiate
acupuncture points from surrounding tissue.34 One
of the histological and anatomical associations with
the meridians is intermuscular or intramuscular loose
connective tissue (fascia).
Ancient acupuncture texts contain several references to “fat, greasy membranes, fasciae and systems
of connecting membranes” through which the qi is
believed to flow.35 In terms of connective tissue associations, several authors have suggested that a connection may exist between the acupuncture meridians,
which tend to be located along the fascial planes
between muscles or between a muscle and bone or
tendon, and the connective tissue.34,35
In view of experimental evidence, it has been
hypothesised that the network of the meridians can be
viewed as a representation of a network of interstitial
connective tissues. These findings are supported by ultrasound images showing connective tissue cleavage
planes at the acupuncture points in human beings.34
Rather than viewing acupuncture points as discrete
entities, it has been proposed that these points might
correspond to sites of convergence in a network of
connective tissue permeating the entire body, similar
to highway intersections in a network of primary and
secondary roads.34

Although separated by two millennia, the traditions of acupuncture and myofascial pain therapies
share fundamental similarities in the treatment of pain
disorders.36 Recent reports have suggested substantial
anatomic, clinical and physiological overlap of the
myofascial trigger points and acupuncture points.36
The analogy between the trigger points and acupuncture points has been discussed since 1977,37 when
100% anatomic and 71% clinical pain correspondences
for the myofascial trigger points and acupuncture
points in the treatment of pain disorders were reported.
A number of similarities between them were also
suggested. The two structures have similar locations
and needles are used at either point to treat pain. The
pain associated with the local twitch response at trigger points is similar to the de qi sensation, and the referred pain generated by needling trigger points is similar to the propagated sensation along the meridians.

“...the traditions of
acupuncture and myofascial
pain therapies share fundamental similarities...”
It was pointed out, however, that the acupuncture
points located at the trigger points are not frequently
used by acupuncturists, and do not share the same clinical indications as the trigger point therapy.38 It was further argued that the claim of 71% correspondence between the acupuncture points and the trigger points37
is conceptually impossible. Furthermore, even putting
this conceptual problem aside, no more than 40% of
the acupuncture points correlated with the treatment
for pain and, more likely, only approximately 18 to 19%
of the points are actually correlated.39 The correlation
between the trigger points and the acupuncture points
clearly need to be further investigated in the future.
The fascial connection theory we propose can
explain the functional connection between dental
occlusion/TMJ and other parts of the body based on
either myofascial release or the qi and meridian system,
or a combination of the two. Therefore, dental occlusion should be built up and maintained in a normal
natural condition, while causes for deterioration of the
TMJ status should be treated in an effort to restore the
natural condition._
Editorial note: This article is a summary of two review papers
recently published in the Journal of Alternative and Complementary Medicine 17 (2011): 995–1000 & 1119–24. A
complete list of references is available from the authors.

_contact

roots

Dr Yong-Keun Lee and
Dr Hyung-Joo Moon are
practicing dentistry at the
Moon Dental Hospital and
ICPB in Seoul in South Korea. They can be contacted
at ykleedm@gmail.com

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[16] => RO0110_01_Titel

I opinion _ instrument design

Fig. 1

Fig. 2

Canal anatomy: The ultimate
directive in instrument design
and utilisation
Author_ Dr Barry L. Musikant, USA

Fig. 1_Mandibular first molar
(mesiodistal).
Fig. 2_Mandibular first molar
(buccolingual).

16 I roots
2_ 2012

_It may sound so basic that one would not even
think to ask the question, but what constitutes an
endodontic education? After teaching thousands of
dentists over many years, I believe that the mechanical aspect of endodontic education is a rote exercise.
The students are presented with a set of instruments
and told how to use them. In the case of K-files, they
may be told that the instrument must first engage
dentine by rotating the instrument clockwise for the
flutes to engage the dentine followed by a pull stroke
that cleaves off the engaged dentine, or they may be
taught to use these instruments with a watch-winding motion combined with an up-and-down stroke
that randomly engages and cleaves small amounts of
dentine away. That the K-file also impacts debris and
distorts curved canals to the outside wall are considered side-effects that will not occur once the dentist
learns how to use these instruments properly. Under
any circumstances, any negative side-effects are not
considered to be due to deficiency of design so much
as the dentist’s lack of skill. This mindset solidifies the

continued use of K-files, even as the introduction of
rotary NiTi has taken increasing hold.
The course of endodontic instrument development might take a different turn if the choice of
instrument design and implementation were based
on critical analysis. As it is, the increased adoption of
rotary NiTi is confirmation that the pre-existing use
of K-files as the sole instruments to shape and
cleanse canals is inadequate. What is ironic is that
while the adoption of rotary NiTi has been most dramatic, drastically reducing the usage of K-files, this
clearly discernible trend has not led to a re-examination of why K-files, now used a good deal less, are
still being used at all. The irony is doubly compounded by the fact that as the vulnerabilities,
namely instrument separation, of rotary NiTi have
become more pronounced, it has led to a rebound in
the increased usage of K-files to further shape the
glide path so the fracture-prone NiTi instruments
are subject to less stress.

[17] => RO0110_01_Titel

opinion _ instrument design

Fig. 3

Increasing the reliance on K-files, a system that
demands a substitute in the form of rotary NiTi,
represents a dichotomy in that neither system is
workable by itself, with the weaknesses of both still
present when combined. The result is a balancing act
in which each tooth presents its own unique conditions for an ever-changing combination of these
two shaping systems, a balancing act that is inherently unstable and leads to a reduced rate of successful outcomes. The most obvious shortcomings
of K-files include the impaction of debris and the
distortion of curved canals to the outer wall—something already attributed to the lack of operator skill.
Rotary NiTi’s greatest shortcoming is unpredictable
separation, a problem intimately associated with
the torsional stress1 and cyclic fatigue2 generated
by this form of motion and compounded in canals
of increasing curvature. The solution to this weakness is the use of these instruments in reciprocation
rather than rotation. The form of reciprocation cho-

sen for these instruments is a hybrid one that still
produces 200 full rotations per minute, reducing but
not eliminating cyclic fatigue,3 while a 30-degree
clockwise stroke compensates for a 150-degree
counter-clockwise arc of motion, significantly reducing the torsional stress formerly generated by
full rotation.
The introduction of a hybrid reciprocating system
without question leads to less instrument separation. Yet, the manufacturer of this system also understood that marketing benefits would be derived
if the system were less expensive with fewer instruments being the most direct way to reduce costs. They
evidently determined that the increased costs for
the one recommended instrument would be acceptable because the overall cost to the dentist for the
procedure would be reduced. All that was necessary
for this new system to be successful was to convince
the dentist that the canal preparations done with one

Fig. 4
Fig. 3_Mandibular second premolar
(mesiodistal).
Fig. 4_Mandibular second premolar
(buccolingual).

Fig. 5_Mandibular incisor
(mesiodistal).
Fig. 6_Mandibular incisor
(buccolingual).

Fig. 5

Fig. 6

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[18] => RO0110_01_Titel

I opinion _ instrument design

Fig. 7

Fig. 8

Fig. 7_Maxillary second premolar
(mesiodistal).
Fig. 8_Maxillary second premolar
(buccolingual).

instrument produce results that are adequate for
predictable success.
The greater our understanding of pulpal anatomy
as it is, rather than an idealistic rendition that makes
for a comfortable fit between results and perception, the better our judgement of what constitutes
proper design and utilisation as it relates to the task
at hand. The several micro-CT scans shown in this
article, generated by Drs Versiani, Pecora and Neto,
clearly demonstrate the typical anatomy of various
teeth (Figs. 1–8). In addition to anastomoses, divergent branching and cul-de-sacs, the most common
feature of pulp tissue is its asymmetric anatomy.4 Far
from displaying a uniform conical shape, it is most
often far wider in the buccolingual plane than the
mesiodistal. Thin sheaths of tissue rather than welldefined canals are often present. These anatomical
variations present challenges to K-files, mostly because of their high level of canal engagement as
they attempt to work themselves apically. They must
be used with repetitive vertical strokes to cleanse
the buccolingual extensions of these tissue sheaths,
a motion that increases the chances of debris impaction blocking further access to the apex. Both
hybrid reciprocating NiTi and full rotary NiTi systems

Fig. 9_A relieved reamer with a flat
side. Note the decreased number of
vertically oriented flutes.
Fig. 10_A K-file. Note the increased
number of horizontal flutes.
Fig. 9

Fig. 10

18 I roots
2_ 2012

tend to stay centred within the canal and, as many
studies point out, the wider extensions of oval canals
are not cleansed. If the canal is prepared to a maximum of 25.08, it may look adequate in the mesiodistal
dimension, but be totally inadequate in the buccolingual plane, where the canal diameter is often five
to six times greater. A canal may look very much like
our ideal preconception in one plane and totally invalidate that perception when seen after 90 degrees of
rotation.
If the cleansing of highly asymmetric canal
anatomy is the goal that drives instrument design,
then what we have at present is too often not up to
the task. What we need are more rational designs
based on a critical analysis of the interaction between
design utilisation and results. Let’s consider the use of
relieved reamers designed with a flat (Fig. 9) along
their entire working length used in a watch-winding
motion that may be generated both manually and
in a 30-degree reciprocating handpiece. All the instruments, including a thin 0.06mm tipped reamer,
have vertical flutes that when used with a horizontal
watch-winding motion will immediately shave dentine away. The vertical pull stroke is simply employed
for carrying the debris occupying the flutes in order

[19] => RO0110_01_Titel

opinion _ instrument design

Fig. 11

to be brought coronally and wiped away. The vertical
orientation of the flutes tends to sweep through any
debris that may be present in the canal when the
reamers are directed apically, rather than impacting
debris apically the way the horizontal flutes on a K-file
(Fig. 10) tend to do.5 With full depth far more easily
attained with a relieved reamer than a K-file, leaning
the vertically oriented blades against a broad sheath
of tissue is more likely to remove that tissue than if the
main function of the blades is to engage and disengage until the pull stroke is employed, an action that
occurs with K-files.
Unbeknownst to most dentists, NiTi instruments
are predominantly shaped like reamers even though
they are still called files. They recognise the inherent
advantages of an instrument that shaves dentine
away rather than first embedding into it. Yet, NiTi
instruments must stay centred, lest they encounter
anatomy that may lock and bind anywhere along
length.6 Locking and binding is good for neither NiTi
nor stainless steel, but where there is a large gap
between deformation and fracture for stainless steel,
NiTi has little room between the two, effectively
allowing for safe usage within very narrow margins.
These narrow safety margins empirically appreciated
by dentists are major incentives for conservative NiTi
canal preparation, which in light of the real anatomy
that must be instrumented can lead to inadequate
shaping and cleansing.
What I am attempting to show here are the possible consequences that occur simply because the
instruments that have been traditionally employed
are not designed to treat the canal anatomy as it is.
It may provide pleasing results when viewed in the
mesiodistal plane, but micro-CT scans clearly tell us
there is far more to the story that must be addressed.
Graduating dentists will be far more able to make

sensible, rational decisions if they are taught instrument design as it relates to function, which in turn
will produce results that are consistent with the
stated goals. That is far better than using instruments
that meet our ideal preconception of a canal anatomy
that often exists nowhere but in our minds._
Editorial note: A complete list of references is available
from the publisher.
Images by Prof. Marco A. Versiani, courtesy of The Root
Canal Anatomy Project (original images can be found at
rootcanalanatomy.blogspot.com)

Fig. 12
Figs. 11 &12_These radiographs
show the ability of flat-sided reamers
(SafeSiders) used in a reciprocating
handpiece (Endo-Express) to shape,
irrigate and clean irregular-shaped
canals effectively. They were used
without the fear of binding or
breakage.

Figs. 1–12 (Courtesy of Dr Barry
Musikant)

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_about the author

Dr Barry Lee Musikant is a member of the American Dental
Association, American Association of Endodontists, Academy
of General Dentistry, Dental Society of New York, First District
Dental Society, Academy of Oral Medicine, Alpha Omega International Dental Fraternity and the American Society for Dental
Aesthetics. He is also a Fellow of the American College of Dentistry. His 35-plus years of practice experience as a partner in
the largest endodontic practice in Manhattan has established
him as one of the top authorities in endodontics.
To obtain more information about Dr Musikant, please visit www.essentialseminars.org,
e-mail info@essentialseminars.org or call +1 888 542 6376.
_contact
Dr Barry Lee Musikant
Essential Dental Systems, Inc.
89 Leuning Street
S. Hackensack, NJ 07606
USA
info@edsdental.com

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[20] => RO0110_01_Titel

I opinion _ WaveOne

WaveOne―
First experiences of
third-year students
Author_ Prof Michael A. Baumann, Germany

Table I_Results of the study
by Roane and Sybala (1984),
showing that most fractured
K-files in daily practice result
from use in CW motion.

2_ 2012

At the turn of the millennium, the first files with
sharp edges, such as FlexMaster (VDW) and ProTaper
(DENTSPLY Maillefer), were introduced to the market
and the triangle cross-section was diversified, ranging from two sharp edges to three (which still is the
most frequently used type), four or five. In addition,
a variety of sizes and tapers were introduced.

In the beginning, that is the 1990s, there was a
debate about the advantages and disadvantages of
the new NiTi files and about an initially high fracture
rate. Before long, knowledge about the behaviour of
the new material, correct handling, auxiliary support
of specific endodontic motors with torque-control
mechanisms and the understanding of cyclic versus
torsional fatigue, the advantage of a crown-down
approach and many, many more details led to a
breakthrough in this new area. The initial fears—that
a rotary instrument would screw into the root dentine
too deeply and become stuck or fractured—led to a
radial land design.

In 2008, Ghassan Yared published his idea of using
only one file from the ProTaper system, the F2 (#25
at the tip and 0.08 taper in the first 3mm), in the ATR
motor, which enabled the user to programme the file
movement in a reciprocating file motion at selfdefined angles and time. This idea goes back to Roane,
who discussed clockwise (CW) and counter-clockwise
(CCW) movement of K-files1 and introduced the
balanced force technique in the early 1980s.2

Number

Percentage

Complete separation CCW

29

5.9

Complete separation CW

37

7.5

Partial separation CCW

0

0

Partial separation CW

21

4.3

Distortions of the flutes CCW

13

2.6

Distortions of the flutes CW

393

79.7

Fractures CW
Fractures CCW

451
42

91.5
8.5

Total

493

100

Table I

20 I roots

_Rotary root-canal instrumentation with NiTi
files has been very successful over the last 20 years.
Starting with ProFile (DENTSPLY Maillefer) in 1994,
the time-consuming and complicated hand instrumentation of root canals, which had dominated
endodontic procedures for more than a century, was
replaced with a totally new approach.

In 1984, Roane and Sybala evaluated 493 used Kfiles from an endodontic practice. In a preliminary test,
new K-files were rotated CW and CCW until they broke
and exhibited a special, totally different and characteristic fracture pattern for each movement. This pattern had been delineated by Chernick et al.3 Roane and
Sybala concluded that file damage predominantly
occurred when the K-files were used in a CW motion
(91.5%), whereas the CCW motion caused distortion
or separation in less than 10% of cases (Table I).
“This observation is explained by the fact that
counterclockwise rotation unthreads the instrument,
decreasing its load and releasing its cutting edge.
Clockwise rotation threads the instrument into the
canal and increases its load until its cutting edges
cease to rotate. At that point, the instrument shaft
must either distort or separate unless the operator
terminates the rotation.”1

[21] => RO0110_01_Titel

opinion _ WaveOne

Fig. 1_WaveOne files: Small, primary
and large.

Small # 021.06

Primary # 025.08

Large # 040.08

Fig. 1

With these facts in mind, Roane et al. published
another article in the following year, describing the
‘balanced force’ concept for instrumentation of curved
canals, in which they state: “Its concepts use force
magnitudes in order to create control over undesirable cutting associated with canal curvature. Rotation is promoted as the means for maintaining magnitude as a control and CCW direction of rotation provides finite operator control.”2 They thus suggested
combining CW and CCW motion in root-canal instrumentation to prevent breakage of K-files and preserve
curved canals much better than before. To obtain this
result, they introduced a new K-type file with a parabolic tip, expecting that the load would be distributed
and reduced to below the regular cutting magnitude.
Today, the balanced force concept is taught in
many dental schools and is well known all over the
world. When the new NiTi instruments appeared in
the early 1990s, the constant rotation of files at a
speed of 250 to 350min-1 appeared to be the gold
standard over the next few decades. With Yared’s
idea4—combining CW and CCW when using NiTi files,
namely the ProTaper F2—both ideas were unified.
Yared suggested the use of a #8 stainless-steel hand
file to negotiate the canal to working length using an
apex locator and #10 or 15 files only in severely curved
canals. This is followed by the 25.08 ProTaper F2. The
CW rotation is greater than the CCW rotation. In this
manner, a CW motion screws the file into the canal
and a CCW motion unscrews it. As CW is greater than
CCW, the file automatically passes more deeply into
the canal and the user is warned to avoid apical pressure that will force the instrument deeper still.
Yared’s idea triggered the design of a new instrument and motor that would fulfil the requirements

of a reciprocating technique, the WaveOne system.
WaveOne is available in three sizes—21.06, 25.08
and 40.08 (Fig. 1)—and comes with the WaveOne
motor, which is programmed to move the file in the
special reciprocating motion. The main advantages
of WaveOne are:
WaveOne enables the realisation of the one-file
concept
Only one file is needed for a single tooth. In some
cases, molars demand two WaveOne files, namely the
small or primary for the buccal and the large for the
palatal canals. This replaces the use of numerous files
necessary in the past. The files may be used as disposable instruments because of a lower price, which
may be accepted more easily by the patient than the
higher prices of a complete set of files used with other
systems.
WaveOne lowers the fracture risk
The fracture risk of NiTi files is low, with a deformation rate of 0.75% for ProFile and 2.9% for ProTaper. Instrument separation occurs in 0.26% for
ProTaper and 0% for ProFile.5 Nevertheless, practitioners still fear file breakage. The reciprocating
motion respects the fatigue threshold of NiTi alloys
(Fig. 2) far better than a constant rotary motion, which
leads to a lower fracture risk than with conventional
NiTi files.
WaveOne reduces the risk of prion transmission
“The risk of vCJD transmission through endodontic procedure compares with other health care risks of
current concern, such as death after liver biopsy or
during general anaesthesia. These results show that

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[22] => RO0110_01_Titel

I opinion _ WaveOne
Fig. 2_Relationship between torque
(gcm) and angle of rotation (degrees).
A NiTi file tolerates about three to four
complete rotations before it factures.
When used in a reciprocating motion,
the angle of rotation always stays
within a rotation of no more than 360°.

120
100
80
60
40
20
0
0

100

200

300

400

500

600

700

800

900

1000

1100

1200

angle of rotation (degrees)
Fig. 2

single instrument use or adequate prion-decontamination procedures like those recently implemented
in dental practice must be rigorously enforced.”6 The
prion decontamination of endodontic instruments
appears to be an extremely difficult procedure. Instruments cannot be cleaned through NaOH, NaOCl
or guanidine thiocyanate immersion for 24 hours or
through steam sterilisation. “Uniformly, debris could
not be completely removed. [...] Based on these findings, single use of nickel-titanium rotaries appears to
be beneficial.”7 This finding led to the recommendation by the Department of Health in the UK in 2007
and some manufacturers of dental instruments to
use disposable (single-use) instruments:
Table II_Instrumentation time using
WaveOne and hand files.

WaveOne (time in s)

Hand files (time in s)

30

251

25

210

38

223

41

129

22

299

14

346

12

163

17

328

34

224

233
23.3

2,173
217.3

Total time
Mean
Table II

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2_ 2012

“The transmission of vCJD via dentistry is considered to be low risk! However, the Department of
Health (DoH) has recently advised dentists to ensure
that as a precautionary measure endodontic reamers
and files are treated as single-use in order to further
reduce any risk of vCJD transmission.”8
In contrast, Julian Webber, the editor of Endodontic Practice, sent a letter to the editor of the British
Dental Journal published in June 2007, requesting
less “draconian advice”.9 Webber stated that no prions
had been found in the dental pulp10,11 and that there
was no proof for the iatrogenic transmission of CJD
in dentistry.12
Schneider et al.13 conducted a study with knockout mice and human teeth using three methods:
immunohistochemistry, cell culture and SEM. They
state, “In human teeth, cementoblasts and odontoblasts showed prominent staining for PrP (Prion
Protein) at levels comparable to those of nerve
fibers. [...] Periodontal and pulpal tissue exposed by
disease or trauma might represent a clinically relevant entry point for prions incorporated orally and
thus a possible mode of infection.” This means they
did not find prions in teeth but a staining of pulpal
cells in several tissues, which indicates that prionlike proteins can be found physiologically in the
dental pulp.
In an initial trial with the aim of collecting information about the routine use of WaveOne files, thirdyear dental students at the University of Cologne,

[23] => RO0110_01_Titel

opinion _ WaveOne

Fig. 3a, b_A plastic block instrumented with WaveOne (#020) and
another after hand instrumentation
(#023). In the middle, the dark/black
area indicates the original canal and
the surrounding grey silhouette
shows the root-canal geometry after
shaping. With WaveOne, a sharp,
continuous and smooth shape was
created. In contrast, a canal instrumented with a hand file is disrupted
and has a more transported shape
with zipping and ledging.

Fig. 3a

Fig. 3b

Germany, were given the opportunity to work with
the WaveOne primary file (25.08). These students
have little experience with root-canal treatment
because they only work on six teeth (two incisors, two
bicuspids and two molars) and a plastic block during
their sixth term. Instrumentation is taught through
the initial use of hand files up to #15 for creating
a glide path and using ProTaper or FlexMaster in a
constant rotary motion with the ATR motor.

In summary, upon initial observation, WaveOne is
a promising system that is easy to learn for first-time
users, results in less breakage and allows the use of
one single-use instrument._

At the end of this course, ten students were selected to participate in a pilot study. The students
were introduced to the handling of WaveOne files
and the balanced force technique. The students
then instrumented endodontic plastic blocks with
WaveOne files and other blocks with hand instruments (K-files) using the balanced force technique
with the #30 AMF and with step-back to #50 to
reach comparable sizes with the 25.08 WaveOne file
(Fig. 3).
The results show that the mean instrumentation
time (without file exchange and rinsing) for WaveOne
with 23,3s was much more shorter than for hand
instrumentation with 217,3s (Table II). The students
were nearly ten times faster with WaveOne than with
hand instrumentation (between 129 to 346 seconds).
No instruments were fractured, which suggests that
even inexperienced students were able to instrument plastic blocks easily and quickly (between 12
and 41 seconds). In addition, the resulting shape with
WaveOne was much better, smoother and without
zip, elbow or ledge formation.

Editorial note: A complete list of references is available
from the publisher.

_about the author

roots

Prof Michael A. Baumann is Head of the
Division of Endodontics at the Department of Operative Dentistry and Periodontology at the University of
Cologne’s Dental School. He was one of the founders
of the German Society of Endodontology (DGEndo)
in 2002 and held positions as vice-president and
president. He has written seven books mainly on
endodontic topics, the most well-known being the
Color Atlas of Endodontology (2009), which originally
appeared in German (in 2007) and has been translated into English, Spanish, Italian and Portuguese. His Pocket Atlas of Endodontology has been
translated into English, French, Portuguese, Turkish, Russian, Taiwanese,
Chinese, Russian and Ukrainian.
Prof Michael A. Baumann
Department of Operative Dentistry and Periodontology
Dental School
University of Cologne
Kerpener Straße 32
50931 Köln
Germany

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[24] => RO0110_01_Titel

I opinion _ NiTi files

Scouting the root
canal with dedicated
NiTi files
Authors_ Dr Gilberto Debelian, Norway, & Dr Martin Trope, USA

Curvatures

Big Radius
Fig. 1

Obliteration + Constrictions

Small Radius
Fig. 2

Fig. 1_A large curvature radius is
noted (blue) in the mesiobuccal (MB)
canal and a small curvature radius
(red) in the distobuccal canal. Metal
fatigue of NiTi files will increase with
small radius curvatures.
Fig. 2_Obliteration (Case I) and
abrupt coronal curvatures and/or
coronal constrictions (Case II) can
contribute to metal fatigue of NiTi
files.

24 I roots
2_ 2012

_The introduction ofnickel-titanium (NiTi) rotary
instrumentation has made endodontics easier and
faster than with hand instrumentation. In addition,
root-canal preparation is more consistent and predictable. However, fracture of NiTi files remains a major risk. Fracture results from either cyclic or torsional
fatigue.1–8
In clinical practice, cyclic fatigue will increase in
curved canals (the smaller the curvature radius or double curvature the higher the risk) and torsional fatigue
in small and obliterated canals (tip lock; Figs. 1–3).
The type of NiTi files (design, taper, size) and the instrumentation technique (crown-down or step-back,
brushing or pecking motions) may overcome these
anatomic challenges and prevent file separation. Another major clinical technique for reducing the risk of
NiTi file separation is to perform coronal enlargement
and manual pre-flaring to create a glide path before
using NiTi rotary instruments (Fig. 4).9–11 It has been
shown in the literature that establishing a glide path

by coronal pre-flaring and manual canal scouting is a
fundamental clinical step for safer use of NiTi rotary
files. Berutti et al.12 have shown that creating a manual glide path with a #20.02 manual stainless steel
(SS) file decreases the frequency of NiTi rotary file
separation by six times. However, creating a glide path
and coronal pre-flare with small SS files (#06–08) in
curved, constricted or obliterated canals will result in
several clinical complications, such as file deformation, buckling, separation and the need to use several
instruments (Fig. 5). This is because SS small-diameter
files are highly flexible, often leading to torsional fatigue and flute deformation. In addition, straightening
of the original canal can occur with the use of even
these small files in severely or double-curved canals.
Recently, FKG Dentaire introduced its Scout-RaCe
and RaCe ISO 10 files, NiTi rotary file systems for mechanical pre-flaring and creating a glide path to replace SS hand filing at this phase of canal preparation.
It has been demonstrated that the use of these NiTi

[25] => RO0110_01_Titel

opinion _ NiTi files

Cyclic Fatigue
Torsial
Fatigue

Fig. 3_Cyclic fatigue of NiTi files
will increase as a result of a small
curvature radius, which is further
exacerbated by keeping the file in
the same position while rotating or
inflexible files. Torsional fatigue
will increase as a result of canal
constriction and obliteration, exacerbated by flexible files (unwinding),
and excessive vertical pressure.

Tip locks
Fig. 3

instruments prior to the main NiTi rotary files better
retains the original canal anatomy, with less modification of canal curvature and fewer canal deviations
compared with manual pre-flaring performed with
SS K-files.8, 12 In addition, challenging canals that
would take a considerable amount of time to initiate
with SS files can be completed quickly with this new
technology.
In this case report, we will present the indications
and protocols for the use of Scout-RaCe and RaCe
ISO 10 files (Fig. 6).

_Scout-RaCe files
This system consists of three NiTi files with a RaCe
flute design (alternating cutting edges), which is considered to be a non threading design owing to its alternating pitch from parallel to spiralled zones.14–17
The surface of these files is electropolished in order to
remove all irregularities produced during grinding.
The tips are non-cutting and rounded. They are produced in lengths of 21 and 25mm with a 0.02 taper.
They have a triangular cross-section and come in
sizes #10 (purple), 15 (white) and 20 (yellow). These
files have two silicon stoppers, one called SMD (safe
memory disc), which lies close to the handle and is

yellow, indicating the taper of the files (0.02), and a
smaller stopper that indicates the length of the files
(red=21mm and blue=25mm). These files are used
in severe single or double-curved canals and they will
primarily scout the canals with minimal coronal flare
(Fig. 7).

Straight Line Access

Clinical protocol for ScoutRaCe files (severe single and double
curvatures):
1. If possible, use a #06 or 08 K-file file
to reach the estimated working
length (WL). Confirm the length with
an electronic apex locator (EAL).
2. Irrigate with NaOCl.
3. With gentle strokes at 600rpm,
widen the canals with the #10, 15
Fig. 4
and 20 Scout-RaCe instruments
to full length. Since these files are
very flexible, avoid excessive pressure to prevent buckling. Irrigate the canals with
NaOCl between files and clean the files if used for
more than four strokes. Use a #15 K-file to obtain a
smooth glide path and confirm the WL with an EAL.
4. Continue with the main NiTi sequence (BioRaCe,
Sequence files, etc.; Figs. 8 & 9).

Coronal Manual
Pre-Flaring

Scouting +
Glide Path +
Patency
Fig. 4_The risk of NiTi separation
is reduced by straight-line access,
coronal pre-flaring and the
establishment of a glide path.

Fig. 5_Manual scouting with SS files.

Manual Scouting

Complications
– Deformation
– Buckling
– Separation

Small diameter and taper
– Several instruments
– High cost

– High flexibility
– Lack of rigidity
– High torsional fatigue

Fig. 5

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[26] => RO0110_01_Titel

I opinion _ NiTi files

Scout files

600 rpm

10/0.02

Fig. 6

15/0.02

+ Bio Race sequence

20/0.02

Fig. 7

26 I roots
2_ 2012

This system consists of three NiTi files with the
same RaCe flute design as described above. They are
produced in lengths of 21 and 25 mm. The difference between Scout-RaCe and RaCe ISO 10 is that
these files progressively increase in taper but maintain the same apical diameter of 0.10 mm. These
three files come in size #10 and tapers of 0.02,
0.04 and 0.06 (Fig. 6).
The SMD silicon stopper is yellow for the 0.02 taper files, black for the 0.04 taper and blue for the
0.06 taper. The colour of the small silicon stopper
indicates length as with the Scout-RaCe files. These
files are meant to be used in constricted and obliterated canals, as well as in abrupt coronal curva-

tures. These files, like the Scout-RaCe files, will also
scout the canals but because of the progressive increase in taper will primarily perform coronal flaring (Fig. 10). The #10.04 and 10.06 RaCe ISO 10 files
are more rigid than the #15 and 20 Scout-RaCe
files, and that is why they are for use with vertical
pressure for constricted or obliterated and curved
canals (will not buckle as easily as Scout-RaCe files)
and are not ideal for double and severe curvatures.
Clinical protocol for RaCe ISO 10 files (constricted or obliterated canals):
1. Use a #06 or 08 K-file to reach the estimated
WL. Confirm the length with an EAL. Remove the
file and verify that the curvature is not severe by
inspecting the file’s surface.

600 rpm

Scout files

10/0.02
15/0.02

+ Bio Race sequence

20/0.02

Fig. 8

Fig. 9

Fig. 10

600 rpm

900 rpm

Race 10 files

600 rpm

Fig. 8_Scout-RaCe files are
extremely flexible because of their
small 0.02 taper. Note that these files
will not remove dentine from the
coronal part of the canal and will
mostly create apical enlargement.
Fig. 9_Clinical case of a maxillary
premolar with a severe curvature.
Fig. 10_RaCe ISO 10 files
will remove mostly the coronal and
middle part of the canal (green
arrows). The tip for the #10.04
and 10.06 files will work freely
(red arrows) after the #10.02 has
reached the WL.
Fig. 11_Clinical case of a maxillary
molar with a severe curvature and
obliterated MB canals. The RaCe ISO
10 files have enough rigidity to
move through the obliteration while
retaining the curvature of the canal.
Coronal space is produced because
of the increasing taper of the files.

_RaCe ISO 10

Race 10 files

Fig. 6_Scout-RaCe and RaCe ISO 10
clinical applications and protocol.
The Scout-RaCe files are used in
severely and double-curved canals,
whereas the RaCe ISO 10 files are
used in obliterated and
calcified canals.
Fig. 7_Clinical case of a maxillary
premolar with an S-shaped
curvature. The glide path created
by Scout-RaCe files allowed the NiTi
sequence to be followed without
straightening the canal or file
separation.

10/0.02
15/0.02

+ Bio Race sequence

20/0.02

Fig. 11

[27] => RO0110_01_Titel

opinion _ NiTi files

Fig. 12a

Fig. 12b

Fig. 12c

Fig. 12d

Fig. 12e

Fig. 12f

2. Irrigate with NaOCl.
3. With gentle strokes at 900 to 1,000rpm, widen the
canal to WL with the #10.02 and 10.04 instruments. If necessary, continue with the #10.06 file
at 600rpm.
4. Irrigate the canals with NaOCl between files and
clean the files if used for more than four strokes.
Use the #15 K-file to obtain a smooth glide path
and confirm the WL with an EAL.
5. Continue with the main NiTi sequence (BioRaCe,
Sequence files, etc.; Fig. 9).

_Conclusion
Scout-RaCe and RaCe ISO 10 NiTi rotary files
offer the following advantages over SS files for
attaining initial flaring and glide path:
_improved speed and efficiency;
_less initial canal transportation in both experienced and non-experienced hands;
_predictable patency;
_limits the need for the initial use of multiple SS
files in constricted and severely curved canals;
_makes severely and double-curved canals predictable for the traditional NiTi instruments that
follow._
Editorial note: A complete list of references is available
from the publisher.

Fig. 12_Clinical images of the access cavity of the case presented in Figure 11, taken through an operating
microscope. All three MB canals were obliterated. Pre-op preparation, only the MB1 canal is visible (a).
Initial preparation of the MB1 canal with RaCe ISO 10 files and after having troughed with ultrasound over
the other MB canals (b). Following preparation of all three MB canals with all RaCe ISO 10 files (c). Following
preparation of all canals with BioRaCe NiTi files to #40.04 (BR5; d). Close-up following complete
preparation (e). All three MB canals obturated (f). The final X-ray is shown in Figure 11.

roots

_about the authors

Dr Gilberto Debelian (Oslo, Norway)
Dr Debelian received his DMD degree from the University of
São Paulo, Brazil, in 1987. He completed his specialisation in
Endodontics at the University of Pennsylvania, Philadelphia, USA,
in 1991. He completed his PhD studies at the University of Oslo in
1997. He is an adjunct visiting professor in the postgraduate programmes in Endodontics at the University of North Carolina at
Chapel Hill and the University of Pennsylvania. Dr Debelian maintains a private
specialist endodontics practice in Bekkestua, Norway.
Dr Martin Trope (Philadelphia, USA)
Dr Trope received his BDS degree in dentistry from University in Johannesburg, South Africa, in 1976. In 1980 he moved to Philadelphia to specialize in Endodontics at the University of Pennsylvania.
After graduating as an Endodontist he continued at the University
of Pennsylvania as a faculty member until 1989 when he became
Chair of Endodontology at Temple University, School of Dentistry.
Dr Trope is now Clinical Professor, Department of Endodontics, School of Dental Medicine, University of Pennsylvania. He is also in private practice in Philadelphia, USA.

roots
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_ 2012

[28] => RO0110_01_Titel

I special _ sterilisation

Infection control
Author_Dr Frank Y. W. Yung, Canada

Fig. 1_An example of a highfiltration protective mask,
which is recommended
for use with dental lasers.
Fig. 2_An example of the submission
of indicators to a testing service for
assessment of office sterilisation
equipment’s effectiveness.
Fig. 3_An example of sterilised
optical fibres and handpieces.
Fig. 4_An example of sterilised rigid
glass tips and handpieces.

More than 20 years ago, a dental patient named
Kimberly Bergalis was diagnosed with Aids. The source
of her HIV infection was her dentist. Even though the
exact path of transmission is still not known, this first
proven transmission of HIV from dentist to patient—
and the subsequent intense coverage by the media—
set off tremendous confusion and panic amongst
dental patients. It was her unfortunate death in 1991
that changed the dental profession almost overnight,
prompting all sorts of new regulations and guidelines, including the sterilisation of dental instruments. The document Guidelines for Infection Control
in Dental Health-care Settings was published by the
US Centers for Disease Control and Prevention (CDC)
on 19 December 2003, providing some of the current
and available scientific rationale for infection-control
practices, for which recommendations were made.1
These suggestions were followed closely by various
governing dental health organisations, including the
US Occupational Safety and Health Administration
(OSHA) and Health Canada.

In dentistry, we see patients from different walks
of life every day and they bring all kinds of pathogens
to our dental offices. It is our responsibility to arrest
the path of these pathogens and attempt to prevent
them from infecting others and spreading beyond
our practices. Following the CDC recommended infection-control guidelines and procedures can help
stop and prevent transmission of infectious organisms through blood, oral and respiratory secretions
and contaminated equipment during the course of
dental treatment. One factor to consider in assessing the risk of contamination is the type of bodily
substances to which dental health-care personnel
(DHCP) are exposed. It is generally understood that
human blood has a high infectious potential.2 In addition to bacteria and fungi, human saliva has been
found to be capable of harbouring many kinds of
infectious viruses.3, 4 Without the benefits of a quick
and reliable reference, DHCP have to assume that
everyone is a potential carrier. This is the fundamental reason that dental practices should have a universal infection prevention protocol.
Amongst many other related issues, the CDC
guidelines explain the manner in which to wear surgical gloves properly and implement a glove protocol. These recommendations will help properly prevent contamination from our patients’ oral tissues
and fluids. Regarding surgical masks, laser ablation
of human tissue or dental restorations can cause
thermal destruction and can create smoke by-products containing dead and live cellular material (including blood fragments), viruses, and possible toxic
gases and vapours. One concern is that aerosolised
infectious material in the laser plume, such as the
herpes simplex virus and human papillomavirus may
come into contact with the nasal mucosa of the laser
operator and nearby DHCP. Although no evidence
exists that HIV or the hepatitis B virus (HBV) has been
transmitted via aerosolisation and inhalation, there
are scientific studies that confirm the risk of this
possible route of contamination.5,6 The risk to DHCP
from exposure to laser plumes and smoke is real,
and, along with other measures such as strong highvolume suction, the use of a high-filtration mask is
strongly recommended (Fig. 1).

Fig. 1

Sterilisation is a multistep procedure that must be
performed carefully and correctly by the DHCP to help

Fig. 2

28 I roots
2_ 2012

[29] => RO0110_01_Titel

ensure that all instruments are uniformly
sterilised and safe for patient use. Cleaning,
which is the first basic step in all decontamination and sterilisation processes, involves the physical removal of debris and reduces the number of micro-organisms on
an instrument or device. If visible debris or
organic matter is not removed, it can interfere with the disinfection or sterilisation
process. Proper monitoring of sterilisation
procedures should include a combination
of process indicators and biological indicators, and should be assessed at least once a
week (Fig. 2). Patient-care items are generally divided into three groups, depending
on their intended use and the potential risk
of disease transmission. Critical items are
those that penetrate soft tissue, touch bone
or contact the bloodstream. They pose the
highest risk of transmitting infection and
should be heat sterilised between patient
uses. Examples of critical items are surgical
instruments, periodontal scalers, surgical
dental burs, optical fibres (Fig. 3) and contact tips (Fig. 4). Therefore, it is extremely
important to examine, cleave, polish and
sterilise optical fibres and contact tips after
each use. Alternatively, sterile, single-use,
disposable devices can be used. Semi-critical items are those that come into contact
with only mucous membranes and do not
penetrate soft tissues. As such, they have
a lower risk of transmission. Examples of
semi-critical instruments are dental mouth
mirrors, amalgam condensers and impression trays. Most of the equipment in this
category is heat tolerant, and should therefore be heat sterilised between patient uses.
For heat-sensitive instruments, high-level
disinfection is appropriate. Non-critical items
are instruments and devices that come into
contact only with intact (unbroken) skin,
which serves as an effective barrier to micro-organisms. These items carry such a low
risk of transmitting infections that they
usually only require cleaning and low-level

Fig. 4

disinfection. Examples of instruments in
this category include X-ray head/cones,
blood pressure cuffs, low-level laser emission devices and laser safety glasses. For
low-level laser therapy, the use of a transparent barrier similar to disposable sleeves
for curing lights is acceptable. For safety
glasses, the use of a low-level disinfectant
is suitable as long as it has a label claim approved by OSHA for removing HIV and HBV.
The disposal of used instruments and excised biological tissues should be managed
separately. A cleaved optical fibre, broken
contact tips, or disposable fibres should be
disposed of properly in a sharps container.
Harvested biological waste should be placed
in a container labelled with a biohazard
symbol. In order to protect the individuals
handling and transporting biopsy specimens, each specimen must be placed in a
sturdy, leak-proof container with a secure
lid to prevent leakage during transport. By
following these guidelines, the spread of
pathogens amongst dental patients, DHCP
and their families can be prevented, and the
passing of Kimberly Bergalis will not have
been in vain._
Disclosure
Dr Yung has no commercial or financial
interest regarding this article.
This article was first published in the Journal
of Laser Dentistry,18/2 (2010): 68–70.
Editorial note: A list of references is available
from the publisher.

_contact
Dr Frank Y. W. Yung
Toronto, Ontario, Canada

roots

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Fig. 3

[30] => RO0110_01_Titel

I industry report _ Produits Dentaires

Analysis of micro leakage using
a self-etching adhesive system
on casting and fiber glass posts
Authors_ Prof Alejandro Paz, Silvia Arias, Abel Vilma, Españon Candelaria & Lucas Condomi, Argentina

not cause any clinically significant changes. We can
say that the structure loses a significant percentage
of its hardness.2 These points revalidate theories that
state that there is an important relationship between
the properties of the dentine and the remaining tooth
structure. Preformed posts do not truly reinforce the
tooth’s root, but rather uniformly distribute the load
and serve as anchors for the tooth reconstruction
material.3, 4
Fig. 1

Fig. 2

Fig. 3

Fig. 4

_Introduction
One of the misconceptions surrounding endodontically treated teeth is that the use of posts
reinforces the remaining tooth structure. Baldissara
et al.,1 for example, showed that an endodontically
treated tooth loses 9% of its moisture, which does

There are various procedures and materials for
cementing preformed posts and reconstructing the
tooth. Resin cements can be a valid alternative even
if their properties are not very similar to the missing
dental tissue. These cements can be self-adhesive,
self-etching or use an adhesive system. Possible materials for cementing fibreglass posts are self-etch
resin cement and conventional resin cements with
self-etch adhesives. From these, we can determine
the most appropriate combination for the best marginal seal. The conventional etching technique produces strong adhesion to prevent marginal leakage.
However, along with the benefits that this brings, this
also causes excessive decalcification.5
Self-etch adhesive systems arose from the need
to avoid unnecessary dental decalcification. These
systems are based on the fixation of dental compos-

Fig. 5_Fibreglass post and dentine.
Fig. 6_Magnification of 400x.

Fig. 5

30 I roots
2_ 2012

Fig. 6

[31] => RO0110_01_Titel

industry report _ Produits Dentaires

Fig. 7

ite after interaction with the dentine the subsequent
formation of the hybrid layer. Its adhesive values
may be somewhat lower than those obtained with the
total-etch technique,6 but the decalcification is substantially lower. It is necessary to discuss whether adhesive systems with lower adhesive value and better
biocompatibility are sufficient to prevent bacterial infiltration within a root canal. Self-etch dental adhesives can be effective in setting prosthetic structures
such as posts, both preformed and cast.7
In an adhesive system, both the adhesive and the
solid substrates must be analysed. Fibreglass posts
are sealed through the binding of the adhesive to the

Fig. 8

Fig. 9

organic matrix of the post and through micromechanical fixation.8 Cast posts generally present
irregularities on their surface, which can serve to
anchor the fixation system.9

Fig. 7_Magnification of 800 x.
Fig. 8_Metal post.
Fig. 9_Metal, cement and dentine.

We must take into account that the solid adherent, the post, can produce movements during the
polymerisation of the cement that can detach the
adhesive. In these cases, gaps10 are formed between
the material and substrate tooth. These spaces allow
bacterial infection. The entry of micro-organisms is
known as micro-leakage.11 To prevent this, slight
pressure must be maintained during the cement’s
hardening time.
AD

48,&.())(&7,9(DQG6$)(
2QO\LQVWUXPHQWVIRUPRVWFDVHV
6LQJOHOHQJWKWHFKQLTXH

COSAE 2

012

Argentin
a
22 - 25 A
ug 2012

XSWR:/

ZZZL5D&HFK

[32] => RO0110_01_Titel

I industry report _ Produits Dentaires

Fig. 10

Fig. 11

Fig. 10_Fibreglass post (Fibrapost).
Fig. 11_Metal post.

The aim of this study was to analyse the marginal
leakage in preformed and cast posts cemented with
self-etch systems based on the visualization of the
interfaces using SEM technique.

_Materials and methods
Endodontic treatment was performed on ten
single-rooted teeth. They were mechanically unsealed
with Gate drills, provided by the manufacturer (Fig. 1),
according to the diameter of the fibreglass post. The
coronal portion was removed for later reconstruction.
We used the Sealacore self-etch dual-cure resin cement system and the Fibrapost fibreglass post (both
Produits Dentaires; Fig. 2).

_author

roots

The root canal preparations were all of the same
length. The cement was distributed inside the root
canal with a lentulo spiral and the post was placed (Figs.
3 & 4). The tooth stump was reconstructed with the
same bonding resin, concluding with the construction of a provisional element. An impression of the cast
post was taken with silicone and the casting was done
with a non-noble alloy.

_Results and microscopic analysis
Fibreglass post
Figure 5 shows the dentine system, cement and
post with no micro leakage (at 45x magnification).
Figures 6 & 7 show excellent bonding with no micro
leakage between the adhesive system, dentine and
fibreglass post (400x–800x magnification). The thin
layer of the Sealacore cement was noticeable..
Cast post
For this type of post, a marginal closure similar to
that produced for the fibreglass posts was observed.
Micro leakage were not seen at a magnification of
600x (Figs. 8 & 9).

_Penetration of the dye
Completing the cut at the cervix showed no penetration of the dye in all the specimens analysed for
both fibreglass and cast posts (Figs. 10 & 11).

_Conclusion

Prof Alejandro Paz
JF Kennedy University
Buenos Aires, Argentina
E-Mail:
alepaz63@ciudad.com.ar

32 I roots
2_ 2012

This was followed by 300 thermo-cycles at temperatures of between 5 and 55°C. The samples were
soaked in methylene blue for a week. Once dry, the
teeth were separated from the provisional part by a
cut at the neck of the tooth. In the root and coronary
part, the presence or absence of micro leakage was
analysed (Philips 505 SEM), as was dye penetration in
the third cervical root. Analysis of micro leakage was
performed using the image with the highest optical
magnification.

The Sealacore self-etch adhesive showed excellent performance for fibreglass and cast posts. This
adhesive system produced an appropriate marginal
closure. For achieving marginal closure, we recommend this type of adhesive system, as it causes less
decalcification._
Editorial note: A complete list of references is available
from the publisher.

[33] => RO0110_01_Titel

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[34] => RO0110_01_Titel

I industry news _ VDW/DENTSPLY

RECIPROC wins innovation prize 2011
category of DZW and pluradent’s German INNOVATIONSPREIS 2011.
During the ADF congress in Paris (November 2011),
out of 56 entries Réciprocité (reciprocation technique)
won the Dental Profession’s Special Innovation Award.
_RECIPROC is probably the most significant
new development since nickel-titanium instruments
were first introduced to rotary preparation of root
canals. RECIPROC completely prepares and shapes
the root canal with one single instrument. The system
was developed to simplify the procedure of preparing
root canals while ensuring maximum security during
the process. Hence, since its launch in March 2011, the
RECIPROC® system has been adopted in numerous
dental offices and clinics replacing manual instrumentation as well as rotary NiTi systems.
At six German dental trade shows, dentists voted
for RECIPROC one-file endo to be awarded first prize
in the materials and instruments for dental treatment

It is the simplicity of working without instrument
changes and only one motor setting, combined with
safety and economic single use, that has dentists convinced._

_contact

roots

VDW
Fax: +49 89 62734-304
info@vdw-dental.com
www.reciproc.com

Everything you like about X-Smart—
with a Plus
_The new generation of the popular X-Smart
endo motor from DENTSPLY Maillefer, the X-Smart
Plus, will allow you to discover the WaveOne reciprocating single-file technique advocated by leading
endodontists. The X-Smart user interface has been
further improved by a large, bright colour screen, with
a colour-coded file library for file selection at a single
glance, making it the endo motor of choice for all
ProTaper Universal users. The X-Smart Plus retains
the familiar X-Smart features such as
the miniature contra-angle head and
the on/off button on the motor handpiece.

_contact

roots

DENTSPLY Maillefer
www.dentsplymaillefer.com

34 I roots
2_ 2012

The motor works in both
reciprocating motion and
continuous rotation. The
file library contains preprogrammed settings for WaveOne, ProTaper Universal, PathFile, Gates and RECIPROC,

as well as eight free programmes for individual settings. It is operated by a rechargeable battery and
in continuous rotation provides a speed range of
between 250 and 1,200rpm and a torque range of between 0.6 and 4Ncm. A warning sound helps you keep
track of the file stress and the auto-reverse rotation
at the torque limit reduces the risk of file breakage.
The X-Smart Plus endo motor from
DENTSPLY Maillefer comes with a three-year
warranty._

[35] => RO0110_01_Titel

You can also subscribe via
www.oemus.com/abo

would like to subscribe to
for € 44 including
shipping and VAT for German customers, € 46 including
shipping and VAT for customers outside Germany, unless
a written cancellation is sent within 14 days of the
receipt of the trial subscription. The subscription will
be renewed automatically every year until a written
cancellation is sent to OEMUS MEDIA AG, Holbeinstr. 29,
04229 Leipzig, Germany, six weeks prior to the renewal date.

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OEMUS MEDIA AG or via E-mail to
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Notice of revocation: I am able to revoke the subscription within 14 days after my order by sending a written cancellation to OEMUS MEDIA AG, Holbeinstr. 29, 04229 Leipzig, Germany.

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roots 2/12

Signature

OEMUS MEDIA AG
Holbeinstraße 29, 04229 Leipzig, Germany, Tel.: +49 341 48474-0, Fax: +49 341 48474-290, E-mail: grasse@oemus-media.de

[36] => RO0110_01_Titel

I industry news _ VDW

Moisture-activated temporary
filling and sealing material
Tempit is packaged in 30 tips of
0.35g each in a jar.

_contact

roots

Centrix
Tel.: +49 221 530978-0
koeln@centrixdental.com
www.centrixdental.com
C

_Still squeezing those messy tubes?
With Tempit, our unit-dose, moisture-activated temporary filling and sealing material, simply inject into a moist prep, tamp
down and then dismiss the patient. Tempit sets in five minutes or less.

Pre-filled, it eliminates set-up
time. Unique delivery provides:
_direct injection without worrying
that the material will harden before
use;
_no clean-up; and
_eliminates the voids you get when
placing other materials.

Tempit was developed specifically
for sealing access cavities between
root-canal treatments. It seals medicaments in and contaminants out
between root-canal treatments.

No more spatulas! No more
tubes or jars!_

12.06.12 16:18 Seite 1
AD

I hereby agree to receive a free trail subscription of
(4 issues per year).
I would like to subscribe to
for € 44 including shipping and VAT
for German customers, € 46 including shipping and VAT for customers outside of Germany, unless a written cancellation is sent within 14 days of the receipt of the trial subscription. The subscription will be renewed automatically every year until a written
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Reply via Fax +49 341 48474-290 to OEMUS MEDIA AG or per E-mail to
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roots 2/12

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Notice of revocation: I am able to revoke the subscription within 14 days after my order by
sending a written cancellation to OEMUS MEDIA AG, Holbeinstr. 29, 04229 Leipzig, Germany.
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OEMUS MEDIA AG Holbeinstraße 29, 04229 Leipzig, Germany
Tel.: +49 341 48474-0, Fax: +49 341 48474-290, E-Mail: grasse@oemus-media.de

[37] => RO0110_01_Titel

Dental Tribune for iPad –
Your weekly news selection
Our editors select the best articles and videos from around the world for you
every week. Create your personal edition in your preferred language.

ipad.dental-tribune.com

[38] => RO0110_01_Titel

I meetings _ AAE

“History & Heritage
—Forging the Future”
AAE holds its annual session in Boston
Author_ Fred Michmershuizen, USA

_The American Association of Endodontists
held its 2012 Annual Session April 18–21 at the Hynes
Convention Center in Boston. The meeting offered
endodontists, general dentists and other specialists
the opportunity to participate in a large selection of
endodontic courses as well as learn about the rich history of the specialty in the United States.
During the four-day event, meeting attendees
could receive continuing education credit from eight
different educational tracks, three of which were new
this year: Exploring the Future, Evidence Based-En-

38 I roots
2_ 2012

dodontics and Orofacial Pain, Oral Pathology and
Trauma. The sessions were offered in a variety of
learning formats.
The popular Master Clinician Series showcased
live, state-of-the-art surgeries, including implant
placement, regenerative endodontic therapy, molar
endodontic microsurgery, the use of cone beam computed tomography and more.
This year’s master clinicians included Dr Paul D.
Eleazer, Dr Shepard S. Goldstein, Dr Mani Moulazadeh,

[39] => RO0110_01_Titel

meetings _ AAE

Fig. 1

Dr Richard A. Rubinstein, Dr Wyatt D. Simons and
Dr John D. West.
On the exhibit hall floor, companies showcased
their products and services.
Roydent Dental Products offered its popular CFiles in new sizes—12.5, 15 and assorted packs 06-10,
all in 21mm and 25mm lengths. The new 12.5 is an
exclusive size to Roydent and allows doctors to make
a half step when instrumentation between sizes 10
and 15.
Nancy Connor, Roydent’s sales and marketing manager, said the C-Files provide an ideal and extremely
effective way to instrument calcified canals. They are
also ideal for locating canals and instrumenting narrow
canals. Their non-cutting tip allows doctors to break
through calcification safely and efficiently.
SS White, which had an expanded booth presence
this year, introduced a full line of endodontic products
driven around the company’s passion toward conservation and efficiency. The offerings included the redevelopment of the V Taper file and many other instruments.
“The V Taper really is unique because it has a
patented variable taper that at the top of the file is

Fig. 3

Fig. 2

much more conservative and allows for the preservation of cervical dentin to a higher degree than any
other file system on the market,” said Tom Gallop, CEO
of SS White. “As we are starting to learn, and as the
endodontic and restorative community is starting to
see, the value of that cervical dentin in terms of the
long life creation of successful restorations is a vital
element, so we feel that with that patented feature
in V Taper files and a lot of the research pointing to
the need to preserve that cervical dentin as much as
possible that we are on the path to creating longer
lasting endodontic procedures and restorative procedures.”
Other product highlights included the introduction of SafeSiders instruments from EDS in a new
31mm size; a new, high-density foam for cleaning
instruments, available from Jordco; new X-treme
endodontic instruments from JS Dental Mfg.; a new
Marwan Abou-Rass (MAR) microsurgical endodontic
instrument line from Hu-Friedy; the Impact Air 45
high-speed, air-powered handpiece from Palisades
Dental; and the introduction of a new Plasma light
source for Seiler microscopes.
The theme of the 2012 meeting was “History
& Heritage—Forging the Future.” Next year’s AAE
Annual Session is scheduled for April 17–20 in
Honolulu._

Fig. 4

Fig. 1_Dr. Richard A. Rubinstein
performs atypical molar microsurgery
during a theater-in-the-round
educational presentation at the 2012.
AAE Annual Session in Boston.
Fig. 2_Companies offer their products and services in the exhibit hall.

Fig. 3_Brant Miles of SS White.
Fig. 4_James Johnsen of Jordco.
Fig. 5_Dane Carlson of Seiler
Precision Microscopes.
Photos: Fred Michmershuizen,
Dental Tribune America.

Fig. 5

roots
I 39
2
_ 2012

[40] => RO0110_01_Titel

I meetings _ events

International Events
2012
IADR General Session & Exhibition
20–23 June 2012
Iguaçu Falls, Brazil
www.iadr.org
Trans-Tasman Endodontic Conference
21–23 June 2012
Queensland, Australia
www.tteconference.com
Skand Endo
23–25 August 2012
Oslo, Norway
nina.gerner@c2i.net
FDI Annual World Dental Congress
29 August–1 September 2012
Hong Kong, China
www.fdiworldental.org

ESMD Annual Meeting
4–6 October 2012
Berlin, Germany
www.esmd.info
ROOTS Summit
18–20 October 2012
Foz do Iguaçu, Brazil
DGET Annual Meeting
1–3 November 2012
Leipzig, Germany
www.dget.de
ÖGEndo International Congress
9 & 10 November 2012
Vienna, Austria
www.oegendo.at
AMED Annual Meeting
16 & 17 November 2012
San Diego, CA, USA
www.microscopedentistry.com
Greater New York Dental Meeting
23–28 November 2012
New York, NY, USA
www.gnydm.com

2013
International Dental Show
12–16 March 2013
Cologne, Germany
www.ids-cologne.de
IFEA World Endodontic Congress
23–26 May 2013
Tokyo, Japan
www2.convention.co.jp/ifea2013
ESE Biennial Congress
12–14 September 2013
Lisbon, Portugal
www.e-s-e.eu

40 I roots
2_ 2012

[41] => RO0110_01_Titel

about the publisher _ submission guidelines

submission guidelines:
Please note that all the textual components of your submission
must be combined into one MS Word document. Please do not
submit multiple files for each of these items:
_the complete article;
_all the image (tables, charts, photographs, etc.) captions;
_the complete list of sources consulted; and
_the author or contact information (biographical sketch, mailing
address, e-mail address, etc.).

I

Image requirements
Please number images consecutively throughout the article
by using a new number for each image. If it is imperative that
certain images are grouped together, then use lowercase letters
to designate these in a group (for example, 2a, 2b, 2c).
Please place image references in your article wherever they
are appropriate, whether in the middle or at the end of a sentence.
If you do not directly refer to the image, place the reference
at the end of the sentence to which it relates enclosed within
brackets and before the period.
In addition, please note:

In addition, images must not be embedded into the MS Word
document. All images must be submitted separately, and details
about such submission follow below under image requirements.
Text length
Article lengths can vary greatly—from 1,500 to 5,500 words—
depending on the subject matter. Our approach is that if you
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We can run an unusually long article in multiple parts, but this
usually entails a topic for which each part can stand alone because it contains so much information.
In short, we do not want to limit you in terms of article length,
so please use the word count above as a general guideline and if
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Text formatting
We also ask that you forego any special formatting beyond the
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Please do not use underlining.
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not add tab stops.

_We require images in TIF or JPEG format.
_These images must be no smaller than 6 x 6 cm in size at 300 DPI.
_These image files must be no smaller than 80 KB in size (or they
will print the size of a postage stamp!).
Larger image files are always better, and those approximately
the size of 1 MB are best. Thus, do not size large image files down
to meet our requirements but send us the largest files available.
(The larger the starting image is in terms of bytes, the more leeway the designer has for resizing the image in order to fill up more
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Also, please remember that images must not be embedded into
the body of the article submitted. Images must be submitted
separately to the textual submission.
You may submit images via e-mail, via our FTP server or post
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which you will be mailing).
Please also send us a head shot of yourself that is in accordance
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Abstracts
An abstract of your article is not required.

Should you require a special layout, please let the word processing
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or endnotes, please let the word processing programme do it for
you automatically. There are menus in every programme that will
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errors can creep in when you try to number footnotes yourself.

Author or contact information
The author’s contact information and a head shot of the author
are included at the end of every article. Please note the exact
information you would like to appear in this section and format it according to the requirements stated above. A short
biographical sketch may precede the contact information
if you provide us with the necessary information (60 words
or less).

Any formatting contrary to stated above will require us to remove
such formatting before layout, which is very time-consuming.
Please consider this when formatting your document.

Questions?
Magda Wojtkiewicz (Managing Editor)
m.wojtkiewicz@oemus-media.de

roots
I 41
2
_ 2012

[42] => RO0110_01_Titel

I about the publisher _ imprint

roots
international magazine of

endodontology

Publisher
Torsten R. Oemus
oemus@oemus-media.de

CEO
Ingolf Döbbecke
doebbecke@oemus-media.de

Published by
Oemus Media AG
Holbeinstraße 29
04229 Leipzig, Germany
Tel.: +49 341 48474-0
Fax: +49 341 48474-290
kontakt@oemus-media.de
www.oemus.com

Magda Wojtkiewicz, Managing Editor

Printed by
Members of the Board
Jürgen Isbaner
isbaner@oemus-media.de
Lutz V. Hiller
hiller@oemus-media.de

Managing Editor
Magda Wojtkiewicz
m.wojtkiewicz@oemus-media.de

Executive Producer
Gernot Meyer
meyer@oemus-media.de

Designer
Josephine Ritter
j.ritter@oemus-media.de

Copy Editors
Sabrina Raaff
Hans Motschmann

Löhnert Druck
Handelsstraße 12
04420 Markranstädt, Germany

Editorial Board
Fernando Goldberg, Argentina
Markus Haapasalo, Canada
Ken Serota, Canada
Clemens Bargholz, Germany
Michael Baumann, Germany
Benjamin Briseno, Germany
Asgeir Sigurdsson, Iceland
Adam Stabholz, Israel
Heike Steffen, Germany
Gary Cheung, Hong Kong
Unni Endal, Norway
Roman Borczyk, Poland
Bartosz Cerkaski, Poland
Esteban Brau, Spain
José Pumarola, Spain
Kishor Gulabivala, United Kingdom
William P. Saunders, United Kingdom
Fred Barnett, USA
L. Stephan Buchanan, USA
Jo Dovgan, USA
Vladimir Gorokhovsky, USA
James Gutmann, USA
Ben Johnson, USA
Kenneth Koch, USA
Sergio Kuttler, USA
John Nusstein, USA
Ove Peters, USA
Jorge Vera, Mexico

Copyright Regulations
_roots international magazine of endodontology is published by Oemus Media AG and will appear in 2012 with one issue every quarter. The magazine
and all articles and illustrations therein are protected by copyright. Any utilisation without the prior consent of editor and publisher is inadmissible and liable
to prosecution. This applies in particular to duplicate copies, translations, microfilms, and storage and processing in electronic systems.
Reproductions, including extracts, may only be made with the permission of the publisher. Given no statement to the contrary, any submissions to the
editorial department are understood to be in agreement with a full or partial publishing of said submission. The editorial department reserves the right to
check all submitted articles for formal errors and factual authority, and to make amendments if necessary. No responsibility shall be taken for unsolicited
books and manuscripts. Articles bearing symbols other than that of the editorial department, or which are distinguished by the name of the author, represent
the opinion of the afore-mentioned, and do not have to comply with the views of Oemus Media AG. Responsibility for such articles shall be borne by the author.
Responsibility for advertisements and other specially labeled items shall not be borne by the editorial department. Likewise, no responsibility shall be assumed
for information published about associations, companies and commercial markets. All cases of consequential liability arising from inaccurate or faulty
representation are excluded. General terms and conditions apply, legal venue is Leipzig, Germany.

42 I roots
2_ 2012

[43] => RO0110_01_Titel

Cordless
with an extra-small head

An extra-small head. No cord. And full power. The Entran cordless
handpiece provides complete freedom of movement and, thanks to
its extra-small head, also gives optimum access to the treatment
site. The torque-controlled automatic direction change and the five
torque levels set new safety standards in cordless endodontics.
wh.com

Endodontics. Cordless!

[44] => RO0110_01_Titel

FIBRAPOST PLUS & SEALACORE DC
ALL-IN-ONE BUILD UP KIT

All you need
for a safe
and complete
core build-up

Produits Dentaires SA . Rue des Bosquets 18 . 1800 Vevey . Switzerland . www.pdsa.ch

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[cover] => roots international No. 2, 2012

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Table of contents

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