Maxillary lateral incisor

MAXILLARY LATERAL INCISOREXTERNAL ROOT MORPHOLOGY

• The overall average length of the maxillary lateral

incisor is 22 mm with an average crown length of 9 mm

and an average root length of 13 mm

• The maxillary lateral incisors are single-rooted, virtually

100% of the time

• Most reported cases of two-rooted maxillary lateral

incisors are a result of fusion or gemination and are

usually associated with a macrodont crown.

MAZEN DOUMANI 2014 1

MAXILLARY LATERAL INCISOR• The root apex and the apical foramen were displaced

distolingually

• The coincidence of the apical foramen and the root

apex was found in only (6.7%) of the specimens.

Therefore, the exploration of the apical foramen and the

constriction with a fine precurved #10 size file tip

and the electronic apex locator, is essential to locate

the foramen.


MAXILLARY LATERAL INCISOR

• the average diameter of the major foramen is 0.4 mm,

while the accessory foramina were 0.2 mm in

diameter.

• The average distance of the major apical foramen from

the anatomical root apex was found to be 0.3 mm.

• Approximately 10% of the maxillary lateral incisors

exhibited accessory foramina.

Apical foramen

Lateral foramen



• An SEM investigation of 14 extracted maxillary

lateral incisors with radicular grooves concluded

that direct communication between the groove

and the pulp was evident in these specimens

and that accessory canals were the primary

mechanism of communication between the

periodontium and the pulp


OEHLERS CLASSIFIED DENS INVAGINATUS INTO THREE TYPES BASED

ON THE SEVERITY OF THE DEFECT.

• Type 1 dens invaginatus is an invagination confined

to the crown.

• Type 2 extends past the cementoenamel junction but

• does not involve periapical tissues.

• Type 3 defect. The invagination extends past the

cementoenamel junction and may result in a second

apical foramen.

1 2 3MAZEN DOUMANI 2014 6

In cases of dens invagination :

• Vitality of the pulp in the main canal has been

shown to be maintained while treating (surgically,

nonsurgically, or both) the accessory canal

system, when there has been no communication

between the two

Vital pulp Treatment is on this

accessory canal


MAXILLARY CANINE

• A small percentage of maxillary canines have two canals(3.5%)

• Of those having two canals, the majority (75%) join in the apical third and exit through a single foramen

• Accessory (lateral) canals are not uncommon and become evident radiographically after the completion of RCT

• The majority of lateral canals occur in the apical third of the tooth

Lateral canal

radicular-form of

dens invaginatus

type 3.

canine


MAXILLARY CANINE

• One individual with an extremely long root

length was reported by Booth in 1988 with

canine teeth having an overall length of 41 mm.

• This patient was a 31-year-old female of Dutch

origin.

• The total incidence of dens evaginatus has been

shown to be approximately 1%


MAXILLARY FIRST PREMOLAR

• The root anatomy of the maxillary premolar

can vary depending on whether one, two, or

three roots are present .



There are some common features to the various

forms of maxillary first premolars: The overall

length of the maxillary first premolar is 22.5 mm .

Prominent root concavities are present on both the

mesial and the distal surfaces of the root.

The mesial root concavity is more prominent and

extends onto the cervical third of the crown. This

results in a root that is broad buccolingually and

narrow mesiodistally with a kidney shape when

viewed in cross section at the cementoenamel junction



The majority of anatomical studies found that the

most common form of the maxillary first

premolar is the two-rooted form.

There was a wide variation

in the incidence of the

number of roots in the

anatomical studies cited.(three canals in two fused buccal roots

and a lingual root.)



• The incidence of three-rooted maxillary first

premolars ranged from 0% to 6%

• Single-rooted maxillary first premolars are

the dominant form in Asian population, and

three-rooted forms are rare



• The majority of maxillary premolars were found to

have two canals, irrespective of whether the tooth

has a single or a double root.

• over 75% of the teeth studied had two canals.

• The incidence of a single canal was significantly

higher in Asian populations compared to the

mixed non-Asian population



• The Weine type IV root canal system, with a

wide buccolingual canal that branches into two

apical canals and foramina in the apical third,

may sometimes be confused as a taurodont-like

root canal anatomy, when it occurs in single-

rooted maxillary premolar teeth.


MAXILLARY SECOND PREMOLAR

• The root tip usually ends as a single blunt apex,

but it may be :fine and divide into two or more,

(rarely three, apices). The curvature in the apical

third is also not uncommon.

One Canal Dividing in Apical Third



• The overall average length of the maxillary

second premolar is 22.5 mm with an average

crown length of 8.5 mm and an average root

length of 14 mm .

• The most common form of the maxillary second

premolar is a single root.

• The incidence of two rooted maxillary second

premolars ranged from 5.5% to 20.4%while the

three-rooted form was a rare finding and ranged

from 0% to 1%MAZEN DOUMANI 2014 18


NOTICE

• Canal exploration of maxillary second premolar

teeth should be done with fine curved files,

keeping in mind the Vertucci or Weine

classification of two canals in one root that

may not be apparent on the radiograph.



Maxillary left second

premolar with a single

root and a single canalMaxillary right second premolar

with a single root and single

canal; the apical third exhibits a

curvature to the mesial.

Maxillary left second

premolar with a single

root and a single

main canal; two lateral

(accessory) canals are

visible in the apical third

of the root.


MAXILLARY FIRST MOLAR

• The maxillary first molar normally has three

roots .

• The mesiobuccal root is broad buccolingually

and has prominent depressions



• The internal canal morphology is highly variable,

• The majority of the mesiobuccal roots contain

two canals.



• The distobuccal root is generally rounded or

ovoid in cross section and usually contains a

single canal.

• The palatal root is more broad mesiodistally

than buccolingually and ovoidal in shape but

normally contains only a single canal

MD

P



• The palatal root generally appears straight onradiographs, there is usually a buccal curvaturein the apical third.

• The overall average length of the maxillary firstmolar is 20.5 mm with an average crown lengthof 7.5 mm and an average root length of 13 mm



• The maxillary first molar root anatomy is

predominantly a three-rooted form(95%), as shown

in all anatomical studies of this tooth

• The two rooted(3.8%) form is rarely reported and

may be due to the fusion of the distobuccal root to

the palatal root or the fusion of the distobuccal root

to the mesiobuccal root.



• The single root or the conical form of root

anatomy in the first maxillary molar is very

rarely reported.

• The four-rooted anatomy in its various forms

is also very rare



• The mesiobuccal root of the maxillary first

molar contains a double root canal system

more often than a single canal



• The mesiobuccal root of the maxillary first

molar contains a double root canal system

more often than a single canal

Pathways of the pulp tenth editionMAZEN DOUMANI 2014 30

MAXILLARY FIRST MOLARThe single-canal system and single apical

foramen in the palatal and the distobuccal root

of the maxillary first molar is the most

predominant form, as reported in all studies,

but multiple canals and more than one apical

foramen variation do exist in 1–3% of these

roots in the weighted studies reported

Two canals in both buccal roots with a

common foramen in each root.Two separate canals in palatal root



Age was found to have an effect on the

incidence of MB2.

Fewer canals were found in the mesiobuccal

root due to increasing age and calcification.

The MB2 canal was found in (71.1%) when

using SOM and in(62.5%) when using

loupes


MAXILLARY FIRST MOLARThere are reports of :

1) two palatal canals in three-rooted teeth

2) three palatal canals in a reticular palatal root

3) five roots (two palatal, two mesiobuccal, and one

distobuccal)

4) C-shaped canals .

5) Of all the canals in the maxillary first molar, the

MB2 can be the most difficult to find and negotiate

in a clinical situationMB

1 2 3

First molar: 6 canals


MAXILLARY SECOND MOLAR

• The maxillary second molar normally has

three roots

• The relative shape of each of the roots is

similar to the maxillary first molar, but the

roots tend to be closer together and there is a

higher tendency toward fusion of two or three

roots.


MAXILLARY SECOND MOLAR• There is also usually more of a distal

inclination to the root or roots of this tooth

compared to the maxillary first molar

• The mesiobuccal root is broad buccolingually

and has prominent depressions or flutings on its

mesial and distal surfaces.

• The mesiobuccal root has almost an equal

incidence of one or two canals



• The distobuccal root is generally rounded or ovoid

in cross section and usually contains a single canal.

• The palatal root is more broad mesiodistally than

buccolingually and ovoidal in shape but normally

contains only a single canal.

• The overall average length of the maxillary second

molar is 19 mm with an average crown length of 7

mm and an average root length of 12 mmMAZEN DOUMANI 2014 36


• The majority of maxillary second molars (88.6%)

in the anatomical studies were found to be three

rooted.

• The closer proximity of the roots results in a

higher incidence of root fusion (25.8%).

• C-shaped canals(4.9%).


MANDIBULAR CENTRAL INCISOR

• single-rooted.

• The external form of the root is broad labiolingually

and narrow mesiodistally.

• Longitudinal depressions are present on both the

mesial and the distal surfaces of the root

• A cross section of the root is ovoid to hourglass in

shape

• The overall average length 21.5 mm with an average

crown length of 9 mm and an average root length of

12.5 mm.



• All of the anatomical studies reviewed reported that

100% of the mandibular central incisors studied were

single-rooted teeth.

• The canal system is either ovoid or ribbon shaped.



• Approximately 12% of the mandibular exhibited

accessory foramina.

• average distance of the apical foramen from the

anatomical root apex was found to be 0.2 mm

Mandibular left central with two

canals and one apex.



A few anomalies are reported for this tooth in the

literature:

A. two canals and two separate foramina

B. dens invaginatus

C. fusion

D. Gemination

E. dens evaginatus that includes a lingual talon cusp and a

labial talon cusp


MANDIBULAR LATERAL INCISOR

The mandibular lateral incisor is single-rooted . and is

comparable in form to the mandibular central incisor.

The external form of the root is broad labiolingually and

narrow mesiodistally.

Longitudinal depressions are present on both the mesial and

the distal midroot surfaces of the root

A cross section of the root is ovoid or hourglass in shape due

to the developmental depressions on each side

The overall length is 23.5 mm with an average crown length

of 9.5 mm and an average root length of 14 mm


MANDIBULAR LATERAL INCISOR

• All of the anatomical studies reviewed reported that 100%

of the mandibular lateral incisors studied were single-

rooted teeth,

• The shape of the canal system is comparable to the

mandibular central incisor and is either round or ribbon-

shapedtwo canals and one

apical foramen


Maxillary lateral incisor

Health & Medicine

Transcript of Maxillary lateral incisor