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transcript

MAXILLARY

II MOLAR

SUBMITTED BY

O.R.GANESAMURTHI1 YEAR M.Sc.D ENDODONTICS

INDEX EXTERNAL ANATOMY OF TOOTH

MORPHOLOGY OF TOOTH

INTERNAL ANATOMY OF TOOTH

PULP CHAMPER

ROOT CANAL SYSTEM

ANOMALIES OF TOOTH

ENDODONTIC CORELATION

CASE REPORT

REFERENCE

INTRODUCTIONThe maxillary second molar is the tooth located

distally from both the maxillary first molars of the

mouth but mesial from both maxillary third

molars. This is true only in permanent teeth.

In deciduous teeth, the maxillary second molar is

the last tooth in the mouth and does not have a

third molar behind it.

The function of this molar is similar to that of all

molars in regard to grinding being the principle

action during mastication. There are usually four

cusps on maxillary molars, two on the buccal and

two palatal

MAXILLARY II MOLAR

Class traits

3 or more cusps

At least 2 buccal

One or more lingual

In general 2 or 3

Average time of eruption : 11 to 13

Average age of calcification : 14 to 16

Average length : 20.0 mm

CHRONOLOGY OF SECOND MOLAR

Arch traits 3 roots: 2 Buccal & 1 Palatal

Crown: Buccolingual > MesioDistal

3 major cusps

MP, MB & DB

Arranged in a tricuspid-triangular pattern

Lesser-sized DL cusp & sometimes missing

Oblique ridge: MP to DB cusp

Buccal cusps are of unequal size

MP cusp is larger than DP

Buccal aspectSmaller crown size

Less prominent DB cusp & narrower MD

Distally inclined BUCCAL roots

Lingual aspectDL cusp is smaller in width & height

LINGUAL root is narrower MD & slightly Distally inclined

No cusp of Carabelli

Mesial aspect

Less numerous Marginal ridge

tubercles

MB & Lingual roots are less

divergent

Distal aspect

Smaller Distal cusps

A greater portion of the occlusal

aspect is visible

Occlusal aspect

MB & DL angles are more acute

ML & DB angles are more

obtuse

More variable pit/groove pattern

More numerous supplementary

groove

Crown is more constricted MD

INTERNAL ANATOMY

PulpMesioDistal section2 horns, MB is higher

Pulp chamber, roof & floor

Canals, narrow

Canal orifice

BuccoLingual sectionPulp chamber is wider

2 horns of equal height

Cross -section3 canals

INTERNAL ANATOMY

PULP CHAMBER

THE PULP CHAMBER OF MAXILLARY 2 MOLAR IS SIMILAR TO THAT OF THE MAXILLARY 1 MOLAR EXCEPT IT IS NARROWER MESIODISTALLY

PULP HORNS- 4

1.MESIOBUCCAL

2.DISTOBUCCAL

3.MESIOPALATAL

4.DISTOPALATAL

ROOF – MORE RHOMBOIDAL IN CROSS SECTION

FLOOR- OBTUSE TRIANGLE IN CROSS SECTION

PULP CHAMBER ANATOMY

ROOT CANALS

if 3 roots are present usually we can see

3 canals

1. mesiobuccal

2. distobuccal

3. palatal

if 4 canal is presentit is in mesiobuccal root but less frequently than in

the 1 molar

ROOT CANAL ANATOMY

ROOTS AND ROOT CANALS

PALATAL ROOT

MESIOBUCCAL

DISTAL ROOT

63 % straight

37 % buccal curve

78 % distal curve

22 % straight

83 % straight

17 % mesial curve

YEAR TEETH

SAMPLE

1 CANAL 1

FORAMEN

1 CANAL 2

FORAMINE

2 CANAL 1

FORAMINE

2 CANAL 2

FORAMINE

1972 294 64.6 % 14.4 % 8.2 % 12.8 %

1974 29 62.1 % _ 13.8 % 24.1 %

1985 100 71 % _ 17 % 12 %

ROOT CANAL AND APICAL FORAMINA IN MAXILLARY 2 MOLAR MESIOBUCAL ROOT

ROOT ANOMALIES

NUMBER

STUDIES

NUMBERS

OF TEETH

3 1272 2.8 % 7.8 % 88.6 % 0.4 %

ANATOMY RALATIONSHIPS IN SITU

The maxillary 2 molar usually is more

closely related to the maxillary sinus than

the maxillary 1 molar

This close relationship may produce

Soreness In the maxillary teeth due to

Maxillary sinusities

ENDODONTICCORRELATION

Significance of average time of eruption, age of calcification, tooth length & root curvature:

IT HELPS IN DIAGNOSIS AND TREATMENT PLAN

TREATMENT IS DIFFERENT IN ADULT AND YOUNG

NECROTIC PULP

Irreversible Pulpitis

Reversible Pulpit'sIrreversible Pulpit's

Necrotic Pulp

Apexogenesis

Pulp Capping or

PulpotomyClosed Apex Open Apex

RCT Apexification

Obturation

ENDODONTIC CORELATIONAN IMPORTANT AID FOR LOCATING ROOT CANAL IS

DENTAL OPERATING MICROSCOPE (DOP).

IT IS USED TO IDENTIFIED CANAL

THE NUMBER OF 2 MESIOBUCCAL CANALS

IDENTIFIED IN

MAXILLARY 2 MOLAR INCREASED FROM

51 % NAKED EYE

82 % MICROSCOPE

93.7 % DOM

DENTAL OPERATING

MICROSCOPE (DOP).

The operating microscope is an indispensable tool for

state-of-the-art endodontic treatment. The specialty

practice should not be without a microscope; this

instrument is useful in all phases of endodontic

treatment from diagnosis to placement of the final

restoration.

Loupes give excellent

magnification and

illumination

An operating microscope.

ENDODONTIC CORELATION WITHPULP CHAMPER

DIAGNOSTIC MEASURES ARE IMPORTANT

AIDS IN THE LOCATION OF ROOT

CANALS ORIFICES

THESE MEASURES

1. OBTAIN MULIPLE PRE TREATMENT

RADIOGRAPHS

2. EXAMINING THE CHAMBER WITH SHARP

EXPLORER

3. TROUGHING GROOVES WITH

ULTRASONIC TIPS

4. STAINING THE CHAMBER WITH 1 %

METHYLENE BLUE DYE

CHAMPAGNE BUPPLE TEST

5. VISUALIZING CANAL BLEEDING

PRE TREATMENT RADIOGRAPHS

The palatal canal is centered between the

mesiobuccal and distobuccal roots in

maxillary molars.

When a second mesiobuccal canal (MB 2 ) is

suspected, a mesial radiograph is often

required to identify it. However, as the

horizontal angulation increases, the clarity of

the radicular anatomy decreases. A 20

degree mesial shift is sufficient to separate

the canals while limiting distortion.

Endo-Ray II film holder.

the operator places the film parallel to

the tooth and perpendicular to

the central ray and as far apical as

possible

digital radiography system

FLOOR OF PULP CHAMBER

MARKEDLY CONVEX

CANAL ORIFICES SLIGHT FUNNAL SHAPE

IN THIS CASE

REMOVAL OF A LIP OF DENTIN

CANAL CAN BE ENTERED MORE IN

A DIRECT LINE WITH THE AXIS

CONVEX PULP CHAMBER

ROOT CROSS SECTION OF THE MAXILLARY 2 MOLAR

ROOT CROSS SECTION-ENDO CORRELATION

PALATAL, MB 2 FLAT SHAPED

MB 1 CIRCULAR, FLAT

DISTOBUCCAL

FLAT,RIBBON SHAPED

NEAR APEX

BALANCE FORCED INSTRUMENTATION METHOD

ROTARY NiTi FILES ALLOWED CONTROLLED

PREPARATION OF THE BUCCAL AND LINGUAL

EXTENSIONS OF OVAL CANALS

The Balanced Force action.

This instrumentation technique uses clockwise/

anticlockwise rotational motion to remove

dentine with flexible stainless steel files or

nickel-titanium files. It is useful for rapidly

removing dentine in curved canals whilst

maintaining curvature (files are not precurved)

RELATIONSHIP OF THE

2 CANAL ORIFICES

CLOSER 2 CANAL ORIFICES

GREATER CHANCE OF 2 CANALS

JOIN AT SOME POINT IN

THE BODY OF THE ROOT

1 CANAL SEPARATE IN TO 2 CANALS

DIVISION IS BUCCAL

AND PALATAL

PALATAL CANAL SPLITS

FROM THE MAIN CANAL

AT SHARP ANGLE IT IS

VISUAL CONFIGURATION

AS LOWER CASE LETTER h

BUCCAL CANAL IS STRAIGHT

PORTION OF THE h

ROOT CANAL ORIFICES

Examination of pulp chamber floor can reveal

clues to the location of orifices and to the type

of canal system present

Rotary NiTi files must be used cautiously with

the type of anatomy because instrument

separation can occur as the files traverses the

sharp curvature in to the common part of

ROOT CANAL WITH ENDODONTIC CORRELATION

TEETH WITH FUSED ROOTS

OCCASINALLY 2 CANALS

1 BUCCAL AND 1 PALATAL

BOTH EQUAL LENGTH AND DIAMETER

THESE PARALLEL

ROOT CANALS

ARE FREQUENTLY

SUPERIMPOSED

RADIOGRAPHLY

BUT THEY CAN

IMAGED BY

EXPOSING

RADIOGRAPH

FROM DISTAL

3 CANAL ORIFICES 2 CANAL ORIFICES

ACCESS CAVITY PREPARATION IN DIFFERENT CANAL

4 CANALS

RHOMBOID

3 CANALS

TRIANGLE WITH

BASE TO

BUCCAL

2 CANALS

ACCESS OUTLINE FORM

OVAL AND

WIDEST

IN BUCCO

LINGUAL

WORKING LENGTH DETERMINATION

Modern electronic apex locators are

reliable instruments that can help the

clinician determine the working length

Successful treatment depends on the

anatomy of the root canal system the

dimension of the canal walls and the final

size of enlarging instruments

J. Morita Root ZX electronic apex locator.

Analytic Endo Analyzer electronic apex locator and electronic pulp tester

SIZE OF ROOT CANAL INSTRUMENTATION

WORKING LENGTH

CANAL CLEANLINESS

IRRIGANT VOLUME

NUMBER OF INSTRUMENT CHANGES

DEPTH OF PENERATION OF IRRIGANT

NEEDLES

IMPORTANT

FACTOR

DISADVANTAGES

INCREASED RISK OF PROCEDURAL ERRORS

ROOT FRACTURES

ACCESSORY CANALS AND ENDODONTICS CORRELATION

APEX SHOULD BE RESECTED 2 TO 3 mm

REMOVES MOST OF THE UNPREPARED

UNFILLED ACCESSORY CANAL

ELIMINATING A POTENTIAL RESERVOIR OF PATHOGENS

ACCESSORY CANALS

FILLED

THERMOPLASTIC

GUTTAPURCHA

ACCESSORY CANALS

REMOVEDSURGICAL

PROCDURES

ROOT RESECTION FOR REMOVALOF ACCESSORY CANAL

Root end resection a bevel

perpendicular to the long axis of a

root exposes a small number of

microtubules

root resection with 45-degree

bevel exposes significantly grater

number of tubules increasing the

chance of leakage into and out of

the root canal to prevent this root

end cavity preparations should

extend coronally to the height of

the bevel

ACCESSORY CANAL ELIMINATION

RESECTIONS

APICAL

RAMIFICATIONSACCESSORY

CANALS

1 mm OF ROOT

RESECTION52 % 40 %

2 mm OF ROOT

RESECTION78 % 40 %

3 mm OF ROOT

RESECTION98 % 93 %

TEETH WITH MINIMAL ORNO CLINICAL CROWN

Short crown may be developmental

defect

Caries left untreated

Fracture under heavily occlusal force

External trauma

Before starting the procedure

clinician should study their root

angulations on Preoperative

radiograph

Examine the cervical crown

anatomy with an explorer

Pulp chamber located at the

center of the crown at the level

Of the CEJ

TEETH WITH MINIMAL,NO CLINICAL CROWN

Depth of penetration bur to reach the pulp canal is

measured on a Preoperative radiograph

clinician reaches this depth without locating the canal 2

radiograph Should be taken before procedure

Straight radiograph

Preparation deviating in a

Mesial or distal side

Angled radiograph

Preparation deviating in a

Buccal or lingual side

The clinician redirect the penetration angle if necessary

Teeth with calcified canal Endodontic correlation

Causes of calcified tooth

Caries

Medications

Occlusal trauma

Use of magnification and

transillumination

Search canal orifices after completely

preparing the pulp chamber

And cleaning and drying its floor ( 70 %

denature ethanol )

Chamber floor is DARKER in color than

its wall

Management of calcified tooth

Developmental grooves

connecting orifices are LIGHTER

in color Than the chamber floor

Staining the pulp chamber floor

with1 % methylene blue dye

Performing the sodium

hypochlorite “CHAMPAGNE

BUPPLE “test

Searching for canal bleeding point

Dentin must slowly be removed

down the root

Use long thin ultrasonic tips under

high magnification of a DOM to

avoid removing too much tooth

structure

The Analytic ultrasonic gold nitride tips are available in

sizes #2 through #5, and NiTi tips are available in sizes

#6 through #8. Pictured left to right are #2, #3, #6, #7, and

#8. Many other configurations are available

The Spartan ultrasonic handpiece has been specifically "tuned" to work the CPR tips.

ULTRASONICS

The CPR tips are available in nitride

(gold-yellow) and NiTi (green, blue, and

purple).

The extremely fine tips coupled with the

small handpiece allow unprecedented

visibility Ultrasonic tips can be used to

remove pulp stones and to cut dentin

while locating additional canals.

As the search moves apically

Two Radiographs must be taken

1. straight on direction

2. angled directions

Very small pieces of lead foil placed

at the apical extent of the penetration

Can provide a radiograph references

Use first a small file K FILE ( #6, #8,

or #10 ) coated with a chelating agent

Coated with a chelating agent should be

introduced In to the canal to determine

patency

This file should be removed until canal

enlargement It should be used in short up and

down movement and In a selective

circumferential filling motion with most of the

Lateral pressure directed away from the

furcation

This safely enlarge the coronal canal and

moves it laterally To avoid the furcation

Stop excavating dentin if a canal

orifices cannot be found to avoid

Weakening the tooth structure

Serious error can arise from

inappropriate attempt canals

Root wall or furcation perforations

can occur

LIMITATIONS

Rotated teethThis case altered crown root relationship

Management of rotated teeth

Radiograph examination is crucial

Initial outline form occasionally can

be created without dental dam

Positioning of bur with long axis of

the tooth

Bur penetration for both depth and

angulations should be confirmed

Frequently with radiographs

CASE REPORTS

Endodontic Miscellany : Maxillary 2 molarwith two canals in the palatal root

During pre-clinical Endodontic on

extracted teeth, a maxillary second molar

was found to have a palatal root with two

canals.

While locating the canals, because of

eccentric location of the instrument in the

palatal canal, a second canal was

suspected.

Placement of another instrument easily

verified the presence of the second canal..

The palatal root canal system was

characterized by two canal orifices

and two canals that appeared to unite

in the apical third of the root.

which constitute type II canal

configuration according to Vertucci's

classification 8 Most of the clinical

literature on the fourth canal in

maxillary molars reports an additional

mesiobuccal canal (MB2)3,4,5. But an

anomalous root morphology that

occurs Infrequently

Table 1: Canal Configurations of

Maxillary second Molar

Year Author Canal configuration

P MB DB

1979 Slowey 2 1 1

1979 Thews 2 1 1

1982 Cecic 2 2 1

1983 Martinez- 1 3 2

1984 Beatty 1 3 1

1988 Bond 2 2 2

1991 Wong 3 1 1

1994 Jacobsen 2 1 1

1997 Hulsmann 1 1 2

Two canals in a single palatal root maypresent in one of the following types

a. Two separate orifices, two separate

canals and two separate foramina.

b. Two separate palatal roots, each

with one orifice, one canal and one

foramen.

c. One palatal root, one orifice, a

bifurcated canal and two foramina

To investigate properly the possibility

of additional canals, the dentist

should:

# understand the complexity of the

morphology of the tooth involved

# take additional off-angle

radiographs

# ensure adequate “straight-line”

access to improve visibility

# examine the pulpal floor for “lines” to

areas where additional canals may be

located

# remove a small amount of tooth

structure that often may occlude a canal

orifice.

The dentist should be suspicious of

additional canals if endodontic files are not

well centred in the canal on the radiograph

or if endodontic files are not well centred in

the canal clinically.

Discussion

Having the information observed from the

radiographs and knowing what

combinations of internal anatomy are

possible, the dentist should be able to

determine what type of canal

configuration is present.

An examination of the floor of the pulp

chamber offers clues to the

type of canal configuration present.

A Five-canal Maxillary Second Molar*

May 2007, Volume 4, No.5 Journal of US -China

Medical Science , ISSN1548-6648 USA

CASE REPORT

The patient was a 35 years old male who

presented with a severe spontaneous pain in

the maxillary right area which had been

constant for one day. The medical status was

unremarkable. Clinical examinations revealed

that tooth-2 had deep mesio-occlusal caries

without pulp exposure and was very sensitive

to cold test.

Radiographic examination disclosed an

unusual anatomical configuration of the

roots, suggesting that four roots might

be present.

A diagnosis of acute pulpitis was made

for tooth-Following local anaesthesia an

endodontic access opening was made

and the pulp chamber was exposed

clearly.

Preoperative radiograph of tooth

Examination of the chamber floor with an endodontic explorer (DG-16) revealed five canal orifices

1.mesiobuccal canal (MB1),

2.mesiobuccal 2nd canal (MB2),

3.mesiopalatal canal (MP),

4.distopalatal canal (DP)

5.distobuccal canal (DB)

The orifice of the mesiopalatal canal was

large, well formed, and located at the

mesiopalatal corner of the pulp chamber.

The distopalatal canal was also large and

well developed and more distal to the

chamber than a single palatal root would

be expected.

The MB2 orifice was found nearly on the

imaginary line between the MBl and MP

orifice, and about 1.5mm palatal to the MBl

orifice

Occlusal view of the access

opening showing MB1, MB2,

DB, and MP canal orifices

Occlusal view of seating

of master point,

displaying five root canal

orifices

All canals were easily negotiated, and

the working length was determined by

using electronic apex locator Root ZX

The root canals were cleaned and

shaped using K-type files and Gates

Glidden drills #2, #3, and #4 with passive

step-back technique.

Apical preparations in the buccal canals

were enlarged to a master file size of 30,

and in the palatal canal to size of 45.

The root canals were copiously

irrigated with 3% H2O2 solution.

Then the canals were obturated with

AH-Plus sealer and gutta-percha

using a lateral compaction technique.

A temporary restoration with IRM was

placed and a permanent restoration

was advised. At the 3 month recall

examination, the tooth was

asymptomatic with normal periapical

Post obturation occlusal view of

the pulp chamber floor showing

all five root canal orifices

Postobturation radiograph

(RVG) displaying five root canals

DISCUSSION

Peikoff classified the anatomical root

and canal variations into six

categories:

(1) Three separate roots and three

separate canals;

(2) three separate roots and four

canals (two in the mesiobuccal root)

(3) three roots and canals whose

mesiobuccal and distobuccal canals

combine to form a common

buccal with a separate palatal

(4) two separate roots with a single

canal in each

(5)one main root and canal

(6) four separate roots and four

separate canals including two palatal.

This study also revealed that occurrence

of „standard' configuration,

3 roots with 3 or 4 canals, was the

most frequent (88.6%).

In addition to Yang et al. result found

that the maxillary second molars had a

C-shaped root in 4.5% and C-shaped in

Chinese population.

A maxillary second molar with 6 canals: A case report

QUINTESSENCE INTERNATIONAL VOLUME 39 • NUMBER JANUARY 2008

A 31-year-old man presented to the dental

clinic with a chief complaint of a fractured

amalgam restoration on the maxillary right

second molar. The patient’s medical history

was non contributory. A preoperative

radiograph taken after removing the

fractured amalgam. Although the cavity

was deep, there were no clinical symptoms.

Therefore, the tooth was restored with a

gold crown

One month later, the patient returned,

reporting prolonged pain to cold on the

restored maxillary right second molar, and

root canal treatment was indicated

Before the access opening was prepared,

we assumed from the preoperative

radiograph that it had two divergent

palatal roots. Immediately after obtaining

access, two mesiobuccal canals were

apparent. When we located one

distobuccal canal, its isthmus suggested

the presence of a second canal.

We established the root canal anatomy to

be as follows: 2 canals in the mesiobuccal

root with one apical foramen, 2 separate

canals in the distobuccal root, 1 canal in

the mesiopalatal root, and 1 canal in the

distopalatal root On the first visit, we

determined the working lengths from the

radiograph using a Root Zx . On the

second visit, the six root canals were

instrumented with a Profile Ni-Ti rotary

file and irrigated with 1mL of 2.5% sodium

hypochlorite after each change of file size

At the third visit, all of the canals were

obturated by a combination of lateral and

vertical compaction compaction

using gutta-percha and Sealapex.The final

radio-graphs and photograph srevealed

the unusual anatomy of six canals filled

with gutta-percha

Preoperative radiograph

All 6 canal orifices in view Two mesiobuccal canals.

2 distobuccal canals 1 mesiopalatal canal

1 distopalatal

canalWorking length determination

of all canals.

Post treatment radiographs (a, b) and photographs (c, d) of the

maxillary right second molar with 6 canals.

DISCUSSIONThe use of microscopes during endodontic

treatments in dental clinics has become

more widespread, and this practice has

made the detection of hidden accessory

canals easier, especially for mesiolingual

canals of the maxillary molars. it is not

necessary to use a microscope to detect

every hidden root canal orifice in the pulp

chamber. There are many studies of the

configurations of apical canals that help

practioners to predict the anatomy and

positions of the pulp chamber and root

canals before access preparation.

However, the average number of canals

in a tooth is merely an indication when

dealing with an individual case. Based

on a study involving 500 pulp chambers

of extracted teeth, Krasner and Rankow

recently proposed new rules for locating

root canal orifices. The rules state that

the orifices of root canals are always

located at the junction of the walls and

the floor, at the angles in the floor-wall

junction, and at the termini of the root

developmental fusion lines.

With sufficient knowledge of tooth

anatomy and an awareness of possible

root canal variations, careful inspection

of preoperative radiographs

and the dentinal map of pulpal floor

should decrease the possibility of

missing canals, even without using

microscopes, and therefore result in

lower failure rates of endodontic

treatment

CONCLUSION

For successful endodontic

treatment, it is helpful to keep in

mind that there is a chance

of encountering a maxillary second

molar with more than 3 or 4 canals,

or even 6, as this case.

REFERENCES

2. ENDODONTICS Fifth Edition

JOHN I. INGLE, DDS, MSD

LEIF K. BAKLAND, DDS

3. ROOT CANAL MORPHOLOGY

4. May 2007, Volume 4, No.5 Journal of

US -China Medical Science ,

ISSN1548-6648, USA

5. QUINTESSENCE INTERNATIONAL

VOLUME 39 • NUMBER 1 •

JANUARY 2008

6. Journal of Endodontic 11, 308-10.

Endodontics

Problem-Solving in Clinical Practice

TR Pitt Ford, BDS, PhD, FDS RCPS

JS Rhodes, BDS, MSc, MRD RCS,

THANK YOU ALL

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