Internal anatomy…
Dr. Abdirahman Musa
Maxillary central incisor
• Average tooth length:22.8 mm
2
Pulp chamber
It is located in the center of crown.
It is broad mesio-distally, with its broadest part incisally.
It has three pulp horns that corresponds to the mamelons
in a young tooth.
Root and root canal
It has one root with one root canal.
Root canal is broad labio-palatally, conical in
shape, and centrally located.
Coronally or cervically ,the canal shape is
ovoid in cross-section but in apical region ,the
canal the is round .
• 17% cases show labial or palatal curvature of
the root
• Lateral canals present in about 24% cases
And when present usually in apical third.
Maxillary lateral incisor
• Average tooth length: 21mm
6
Pulp chamber
The shape of the pulp chamber is similar to the maxillary
central incisor.
It has only two pulp horns, corresponding to the
developmental mamelons.
Root and root canal
Configuration of the root canal is conical but it has a
finer diameter than maxillary central incisor.
In cross-section, the canal is ovoid labio-palatally in the
cervical third and ovoid in the middle third & round in
the apical third.
• Lateral canals are more frequent (26%)
than in maxillary central incisors
• Majority shows distal curve(53%) whereas
others are straight.
Maxillary canine
• Average tooth length: 26mm
10
Pulp chamber
It has the largest pulp chamber than any single rooted tooth.
Mesio-distally it is narrower and may resemble like flame.
In cross-section it is ovoid in shape, with greater diameter
labio-palatally.
Only one pulp horn is present.
Root and root canal
11
Single root canal of maxillary cuspid is larger
than that of maxillary incisor.
It is wider labio-palatally than its mesio-distal
diameter, and on reaching middle third, it taper
gradually to an apical constriction.
In cross-section, root canal is ovoid in the
cervical and middle third and generally round in
the apical third.
• One report stated presence of straight root in
39% cases whereas a distal curve in 32%
• Lateral canals are present in 30% cases
Mandibular central incisor
• Average tooth length: 21mm
14
Pulp chamber
It is smallest tooth in the arch.
Three distinct pulp horns present.
Pulp chamber is wide and ovoid labio-lingually and it
tapers incisally.
Root and root canals
It has one root which is flat and narrow mesio-distally
but wide labio-lingually.
It may have a distal labial curvature.
Canal is broad in the cervical & middle thirds of root in
labio-lingual aspect which tapers towards apex
• Canal configuration varies as :
one canal exiting in one apical foramen:70%
one canal bifurcating into two canals
,coming together and exiting into one apical
foramen :22%
• A second canal, when present, is lingual to
primary canal.
Mandibular lateral incisor
• Average tooth length: 21mm
Pulp chambers
Same as mandibular central incisor but it has larger
dimension.
18
Root and root canal
Larger than mandibular central incisor.
Majority of root are straight.
It may also have distally , labially curved root
as central incisor but the distal curve is
sharper.
Mandibular canine
• Average tooth length: 22.5mm
21
Pulp chamber
It is small and flat mesio-distally.
One pulp horn is present.
It is wide and ovoid mesiodistally and tapering incisally.
.
Root and root canal
It is usually single rooted.
 It usually has a single canal exiting in one apical
foramen.
Root canal is broad in middle third and taper to
constriction in the apical third in labio-lingual view
• Most of these tooth have single root(68%) but
some have a distal curvature(20%)
Concluding
• Of all phases of anatomic study in human
system one of the most complex is pulp cavity
morphology
• A profound background knowledge of pulp
anatomy is a must in success of any
endodontic treatment
References
• Nisha Garg text book of endodontics.
• Grossman’s endodontic practice
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