The success of endodontic treatment is directly related to the clinician’s ability to remove maximum number of bacteria from the root canal system.Some teeth are more difficult than others due to access limitations or anatomy, but the problem that faces all of us, in every tooth, is our inability to measure the absence of bacteria within the root canal and the potential for microanatomy to exist at any level of the root—whether it is a five-canal molar or a single-rooted anterior. For more information, you can book an appointment at Dr Sachdeva's Dental Aesthetic And Implant Institute, I 101, Ashok Vihar Phase 1, Delhi- 110052 Contact us at • Phone : +919818894041,01142464041 • Our Websites: • www.sachdevadentalcare.com • www.dentalclinicindelhi.com • www.dentalimplantindia.co.in • www.dentalcoursesdelhi.com • www.facialaestheticsdelhi.com • Google+ link: https://goo.gl/vqAmvr • Facebook link: https://goo.gl/tui98A • Youtube link: https://goo.gl/mk7jfm • Linkedin link: https://goo.gl/PrPgpB • Slideshare link : http://goo.gl/0HY6ep • Twitter Page : https://goo.gl/tohkcI • Instagram page : https://goo.gl/OOGVig

1. The myth of
'easy' root
canals in
endodontics

2. 1. No teeth are easy
• The success of endodontic treatment is directly related
to the clinician’s ability to remove maximum number of
bacteria from the root canal system.
• If we can agree that all root canal treatment is
associated with a certain degree of skill and precision
in spite of perceived ease of treatment, I think it is fair
to say there are no easy root canals.
• Some teeth are more difficult than others due to
access limitations or anatomy, but the problem that
faces all of us, in every tooth, is our inability to
measure the absence of bacteria within the root canal
and the potential for microanatomy to exist at any level
of the root—whether it is a five-canal molar or a
single-rooted anterior.

3. • The use of an apex locator can aid in this
determination, but there is often disagreement
between radiographic information and an apex locator,
even in single-rooted anterior teeth, because the canal
terminus can be at the radiographic apex or as much
as 3 mm from it.
• All instrumentation techniques leave a certain amount
of the canal wall untouched, and we are not able to
sterilize the root canal system.
• The apical portion of any tooth may have dentinal
tubules that can harbor bacteria, and the concept of a
single uniform canal opening at the apex is anything
but accurate. Many teeth will have multiple portals of
exit that may or may not be present in the apical third
of the root.

4. Preoperative (left) and post-treatment (right) images
of a heavily restored maxillary central incisor with a
necrotic pulp. A prominent lateral canal can be seen,
but there is no way to know if multiple microscopic
branches are present at any level of the root canal
system.

5. 2. The perception of ease
may not be accurate when
considering anatomy
• Most endodontists will treat the standard four-canal
molar in approximately one hour, and I am no
different. Obviously some clinicians are more efficient
than others and this, along with anatomy, will
influence treatment times and outcomes. With this in
mind, logic dictates that a premolar should be treated
in significantly less time due to increased access with
less canal anatomy. However, a significant subset of
premolar teeth will require as much or more time to
complete than the standard molar root canal due to
anatomical complexity. Let’s look at the “easy” teeth

6. Maxillary incisors
• As an endodontist who sees patients on a referral
basis, treating a central incisor is a relatively rare
occasion unless the etiology is traumatic in origin.
• In these cases, the patient is usually younger, and
this poses its own challenges with large canals and
incompletely developed root ends.
• If the patient has a history of trauma at a young age, it
is not uncommon for pulp canal obliteration to occur,
which results in a complete closing of the root canal
space and significant difficulty in locating the canal.
• In spite of age or etiology, there is a shelf of dentin on
the lingual just below the cemento-enamel junction
(CEJ) that needs to be removed during access or the

7. Maxillary Lateral incisors
• Lateral incisors can be relatively long given the overall
size of the canal and a curve at the apex is often
multiplanar.
• The apex may curve to both the distal and lingual,
making it difficult to clean initially or impossible to
retreat if the root canal is not successful.
• As with central incisors, there is a prominent dentin
shelf on the lingual at the level of the CEJ, but in
contrast to centrals there can be more angulation
between the crown and root, resulting in increased
difficulty cleaning the lingual wall.

8. Maxillary canine
• Maxillary canine teeth don't tend to have as much
curve at the apex as lateral incisors, but they are
very long and can also be large in the buccal-lingual
dimension, making it difficult to disrupt and remove
biofilm from each of the canal walls.
• Again, a prominent shelf of dentin is present on the
lingual aspect at the CEJ that needs to be removed
for straight-line access and the ability to remove
biofilm from the lingual wall.

9. Mandibular incisors
• These are my least favorite teeth to treat. Most are
heavily restored and the mesial-distal dimension is
very small, resulting in no margin for error when
locating the pulp chamber.
• Additionally, there can be significant inclination
between the crown and root, and many will have two
canals or branching at some level of the canal.
• This lingual inclination of the root results in difficulty in
obtaining straight-line access into the buccal canal
and makes locating the lingual canal almost
impossible in some cases, especially if the lingual
shelf of dentin is prominent.

10. Mandibular anterior teeth
will often
have two canals. The
second canal is lingual to
the main canal, and it is not
uncommon for the two
canals to join at the apex.
Tooth No. 24 has a necrotic
pulp and based on the
anatomy of teeth Nos. 23
and 26, a second canal in
tooth No. 24 should be
expected.

11. Maxillary premolars
• While mandibular incisors are my least favorite teeth
to treat, the premolar teeth also provide significant
reason for concern as they have highly variable
anatomy.
• The maxillary first and second premolars will have
one, two, or three roots and canals.
• Maxillary premolar teeth have the smallest mean
apical dimension at the apex and the most variable
anatomy, with exception of third molars.

12. Maxillary premolars with three canals. These teeth
will have two buccal canals and a lingual canal.
The two buccal canals will most often share an
orifice and branch several millimeters apical to the
pulpal floor. The disto- buccal canal is typically the
easier of the two canals to enter into, and the
mesio-buccal can be overlooked.

13. • The roots are often very thin, and a bulbous clinical
crown may have significant taper to a thin root in the
mesial-distal dimension that is broad in the facial-
lingual dimension. It is not uncommon to see mesial-
distal fractures in maxillary first or second
premolars.
• Maxillary second premolars may have more
curvature in the apical portion of the root when the
sinus is close to the root ends.

14. This patient was referred due to continued pain
following root canal treatment in teeth Nos. 4 and
5. An angled radiograph indicated a high
probability for an untreated canal in tooth No. 4
and as a result, this tooth was retreated.

15. At the time No.4 was retreated, there was increased
concern about the anatomy in tooth No. 5. This tooth
was subsequently retreated due to persistent
symptoms.

16. The final radiograph confirms that untreated canals
were present in both Nos. 4 and 5 following the
initial root canal treatment.

17. Mandibular premolars
• Mandibular premolars can be very difficult to treat and
are associated with a high rate of post-treatment
disease that is most likely due to anatomic variability.
• This anatomical variability in mandibular premolars is
similar to that of maxillary premolars and is a possible
reason why root canal treatment may fail in premolar
teeth in general.
• Similar to maxillary premolars, the clinical crowns
taper to a thin root at the CEJ, resulting in very little or
no margin for error when accessing the pulp chamber.
• It is not uncommon to have more than one canal in
these teeth. Several studies indicate that a
second canal is present in more than 25% of
mandibular first premolars. Often when two canals are

18. • Many mandibular first premolars have significant
lingual inclination of the root, making the second
canal almost impossible to locate because the
lingual canal often branches off the main canal at or
near a 90-degree angle.
• If a single canal is present, it tends to be broad in the
buccal-lingual direction, and this makes it difficult to
remove biofilm from all root surfaces.
• Mandibular second premolars also have a high
degree of anatomic variability, but not to the same
degree as mandibular first premolars.
• The reported incidence of multiple canals in
mandibular second premolars ranges from 1.2% to
29%.
• As with first premolars, many mandibular second
premolars have some lingual inclination of the root

19. Mandibular premolars with multiple canals. Both of
these teeth had a single orifice with branching at
various levels of the root canal system.

20. The preoperative anatomy of the first case is
irregular
with conventional radiography, and this branching
could be better
visualized with CBCT.

21. Molar teeth have more predictable
canal anatomy
• Although there are exceptions to every rule and the
potential for anatomic variability has to be considered
in every tooth, for the most part molar teeth have
consistent root canal anatomies.
• There has been increased awareness about the
presence of a mid-mesial canal in mandibular molars
over the last several years, and the use of cone beam
computerized tomography has increased both our
awareness and ability to locate this “extra” canal.
• I consider all teeth that I treat have one extra canal
than is expected, and so I am never surprised by what
I find. If I access a mandibular molar with the
expectation that four canals exist (and there could be

22. • The vast majority of mandibular molars that I treat
have four canals: two well-defined mesial canals
that may or may not join in the apical one-third of
the root and either two distinct canals or a dumbbell
shape in the distal root.
• Because of the broad buccal-lingual dimension of
the distal root, I almost always treat this root canal
system as though it were two canals.

23. A mandibular molar with a distinct mid-mesial
canal. Although molar teeth can, and often do
have variable anatomy, most mandibular molars
are going to have at least three, and more
commonly four canals.

24. This image shows common anatomy encountered in
mandibular molars

25. • No tooth gets more attention than the maxillary first
molar because of the MB2 canal or what some
clinicians refer to as the mesial-lingual canal.
• To be most accurate, I refer to this canal as the
mesial lingual because in many teeth it has no
relationship to the mesial-buccal canal.
• Without question, the most common questions I get
about root canal anatomy relate to this specific canal
space.
• How often is it there? How often can it be located?
Where is it located? Does it join the mesial-buccal
canal?
• These are important questions that deserve more
attention, because this canal can be difficult to locate

26. • Some mesial-lingual canals are located at the level
of the pulp chamber directly lingual to the mesial-
buccal canal, and these canals are going to be more
easily located than the ones that are 1 mm or 2 mm
apical to the pulpal floor and significantly more
mesial than the mesial buccal.
• Bottom line: The mesial-lingual canal orifice is
variable in its lingual extent and in both the mesial-
distal and coronal-apical position,
• But it is present with such a high frequency that a
thorough exploration of the area, aided by enhanced
magnification and illumination, should yield positive
results in 90% of maxillary first molars and a slightly
lower percentage in maxillary second molars.
• In my experience, the closer the two canals are at

27. An example of a maxillary molar with two mesial
buccal canals. The two canals were very close in
the chamber, but branched in the apical portion of
the root to exit via distinct openings.

28. This last image shows the most common anatomy of
the maxillary molar: four canals total with the two
canals in the mesial buccal root joining to exit a
common foramen.

29. • Molar teeth, both maxillary and mandibular, present
challenges to the clinician because multiple canals
are present and access can be limited, making
visualization and rubber dam placement more
challenging compared to other groups of teeth.
• However, the anatomy is often less variable and
more easily located in molar teeth and a greater
amount of tooth structure is available, thereby
increasing the margin for error.
• Access and line of sight may be more straightforward
in premolar and anterior teeth, but anatomical
variability is common.
• In many instances, the anterior and premolar roots
have a small mesial-distal dimension and making an
ideal access opening to locate canals and preserve

30. • When the frequent branching occurs in anterior and
premolar teeth, it will usually happen well below the
pulpal floor at the mid-root level of the canal and this
makes locating and cleaning many of these spaces
very difficult and nearly impossible.
• Because the number of root canals can be variable
and the shape, size, amount, and location of the
microanatomy is unpredictable in all teeth, I think it
is fair to say that no root canal treatments should be
considered “easy.”

31. I 101, Ashok Vihar Phase 1, Delhi- 110052
Contact us : +919818894041,01142464041
Our Websites:
www.sachdevadentalcare.com
www.dentalimplantindia.co.in
www.dentalclinicindelhi.com
www.dentalcoursesdelhi.com
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Facebook link: https://goo.gl/tui98A
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