PREOPERATIVE ASSESSMENT PREOPERATIVE ASSESSMENT OF IMPACTED MANDIBULAR OF IMPACTED MANDIBULAR

AND MAXILLARY 3AND MAXILLARY 3rdrd MOLARS MOLARS

introductionintroduction

Minor oral surgeries can give a false impression that less skill and care are required.

A minor sugery should not produce a major morbidity

Proper assessment prevents or minimise complications

Introduction Introduction

ETIOLOGYETIOLOGY

THEORIES OF IMPACTION

STRONG INDICATIONS FOR REMOVAL

Den cl N A, V38, N2. Den cl N A, V38, N2.

CONTRAINDICATION

LOCAL ASSESSMENT

ASSESSMENT OF IMPACTED TEETH

LINGUAL NERVELINGUAL NERVE

Clinical and anatomical observations on the relationship of the lingual nerve to the mandibular third molar reg1ion. J Oral Maxillofac Surg 41:565,1984

2.28 mm + 1.9

RADIOGRAPHIC ASSESSMENT

Radiographs of third molars must Radiographs of third molars must show the show the

Sensitivity 24% to 38% ajomsSensitivity 24% to 38% ajoms

RADIOLOGICAL ASSESSMENT AIDS IN DETERMINING

CLASSIFICATION

◦ WINTER’S (1926) Based on angulation of long axis of 3rd molar to

long axis of 2nd molar

ajoms

According to the relation of the impacted tooth to the ramus of the mandible & the 2nd molar

PELL AND GREGORY CLASSIFICATION (1933)

Third-molar impaction classified according to the critieria of Pell and Gregory.

Sensitivity 15% onlySensitivity 15% only

ADA NOMENCLATURES

Combined ADA & AAOMS classification of procedural terminology

WHARFE ASSESSMENT

Difficulty Index for removal of impacted mand third molars

Difficulty index

◦ Very difficult : 7 to 10◦ Moderately difficult : 5 to 7◦ Minimally difficult : 3 to 4

Difficulty index for removal of impacted mand.Third molars

ding to J. P. Rood, B. A. A. Nooraldeen Shehab, Darkening of the root (Howe and Poyton,

Main).DeflectofMacgregor, Killey and Kay)

Radiological prediction of inferior alveolar nerve relation

Put jc

Darkening of the root

Loss of density of rootShows overlaping93.1% showed this sign

Deflected roots

Abrubt deviation

Roots may be hooked

Narrowing of roots

implies that the greatest diameter involved by cannal

Deep grooving or perforation may be their

Dark & bifid root

Nerve cross the apex

Double periodontal membrane of bifid apex

Interruption of white line

Diappeares as it reaches the tooth

Diversion of cannal

Change of direction due to displacement of cannalNerve may pass through root

Narrowing/ hour glass apperance

Downward displacement of cannel

ASSESSMENT OF DEPTH OF TOOTH ASSESSMENT OF DEPTH OF TOOTH IN ALVEOLAR BONEIN ALVEOLAR BONE

WHITE LINE

Amber line

Red line

Point of application of elevatorPoint of application of elevatorDepth -More than 5mm – GADepth -More than 5mm – GA

Distoangular impactions - red line-distal CEJ of impacted 3rd molarDistoangular impactions - red line-distal CEJ of impacted 3rd molar

Assesment of 2Assesment of 2ndnd molar molar

If 2nd molar roots are smaller in relation to the impacted tooth or if the roots of 2nd molarare fused & conical, surgeon must be carefulnot to luxate 2nd molar during elevation.

Absence of 1st molar leaves 2nd molar Unsupported

LOCALIZATION OF IMPACTED TEETH USING RADIOGRAPHS

Localization of impacted third molar using radiographs

TUBE SHIFT TECHNIQUE

If canal moves upwards then it is bucally placed .If it moves downwards then lies lingual to roots.

CLARK’S HORIZONTAL TUBE SHIFT

MAXILLARY THIRD MOLAR IMPACTION

ASSESSMENT OF IMPACTED MAX 3rd MOLAR

ARCHER’S ANATOMIC CLASSIFICATION

PELL & GREGORY – RELATIVE DEPTH IN RELATION TO 2ND MOLAR

DIFFICULTY FACTORS

ConclusionConclusion

• IMPACTED TEETH – ALLING , HELFRICK• CONTEMPORARY ORAL AND MAXILLOFACIAL

SURGERY,4TH EDITION-LARRY.J.PETERSON,JAMES.R.HUPP,MYRON.R.TUCKER

• MINOR ORAL SURGERY- GEOFRY L. HOW• TEXT BOOK OF ORAL AND MAXILLOFACIAL

SURGERY, BALAJI• TEXT BOOK OF ORAL AND MAXILLOFACIAL

SURGERY, SHRINIVASAN• BR JR OF ORAL AND MAXILLOFACIAL SURGERY

1990; 28: 20-25• J ORAL MAXILLOFAC SURG 2003; 61: 417- 421• J ORAL MAXILLOFAC SURG 2005; 63: 3-7• DENTAL CLINICS OF NORTH AMERICA – VOL

38.NO:2 APRIL 1994

References

Thank youThank you

Condition of the Masticatory mucosa in relation to the adjacent tooth.

If planned under GA, other impacted teeth should also be considered for removal.