Introduction to Radiological Interpretation Abdul Rahim b Ab Hamid (0813913)

Objectives of Radiograph Interpretation To identify the presence or absence of

disease To provide information on the nature

and extent of disease To enable formation of differential

diagnosis

Suggested systematic sequence for viewing this OPG

Guidelines for interpreting bitewing radiograph

Distal aspect of upper posterior

molar

Consider each upper tooth individually

Distal aspect of upper canine*

Distal aspect of lower canine*

Consider each lower tooth individually

Distal aspect of lower posterior

molar

Suggested sequence of examining individual tooth

Trace the outline/shape of the pulp chamber (reactionary dentin,pulp stone)

Presence and state of existing restoration (recurrent caries)

Any alteration in dentin density (approximal caries, occlusal caries)

Any alteration in the interproximal enamel density (interproximal caries)

Any alteration in the outline shape eg.possible cavitation

Trace the outline of dentino-enamel junction

CROWN: Trace the outline of the edge of the enamel cap

Note any alteration in the density of root dentin (root caries)

Note any alteration in the outline (cavitation cause by root caries)

NECK/ROOT: trace the outline of the neck and cervical 1/3 of the root of the tooth

Dental caries & periodontal diseasesAbdul Rahim b Ab Hamid (0813913)

Dental Caries Common infectious diseases, strongly

influenced by diet and affecting 95% of population

Primarily caused by mutan streptococci including S.Mutans, S. Sobrinus and etc

Common classification of dental caries Pit or fissure

-occlusal-buccal @lingual pit)

Smooth surface -approximal-buccal or lingual surfaces-root

Recurrent caries

Methods of diagnosing caries at different sites Thorough, careful clinical

examination using -Direct vision of clean and dry teeth-Gentle probing-Transillumination

Radiographic examination using:-bitewings in adult and children-periapical radiograph

Rationale and frequency for the use of intraoral radiograph It can reveal carious lesion that

otherwise might go undetected during thorough clinical examination

Frequency decided on the basis of a patients' needs, considering factors of oral hygiene, fluoride exposure, diet, caries history, restorative care and exposure

Examination from radiograph

Posterior bitewings radiographs are the most useful x-ray projections for detecting caries in distal third of the canine and the interproximal and occlusal surfaces of premolars and molars

Periapical radiographs are useful primarily for detecting changes in the periapical and interradicular bone

Children’s caries radiographic examination should include bitewing films

Diagrams illustrating the radiographic appearances and shapes of various lesions, EDJ*OPG is not recommended for diagnosis of caries, however they may demonstrate ooclusal caries, particularly in molar better than bitewings

Radiographic appearance of dental cariesOcclusal caries

Incipient occlusal caries

Moderate occlusal caries

Severe occlusal caries

Incipient proximal enamel caries

Moderate enamel proximal caries

Advanced proximal caries

Severe Proximal Caries

Facial, Buccal, Lingual caries

Root surface (cementum caries)

Recurrent caries

Rampant caries in children

Radiation caries in post radiation patient

Radiographic appearance of other important shadows Radiolucent cervical burn-out or

translucency The radiopaque zone beneath amalgam

restoration

Cervical burn-out Artefactual phenomenon created by teeth

anatomy and variable penetration of X-ray beam

Can be explained by considering all the different parts of tooth and supporting tissues the x-ray has to penetrate

Crown-dense enamel cap and dentine Neck-only dentine Root- dentine and the buccal & lingual plates

of alveolar bone

Cervical burn-out

Cervical burn-out Diagnostic importance because of its similarity to

the radiolucent shadows of cervical and recurrent caries

Can be distinguished by, Located in the neck of teeth, demarcated above by

enamel cap or restoration and below by alveolar bone level

Triangular in shape, gradually become less appearance towards the centre of the tooth

Affected all teeth usually, especially smaller premolar Root & recurrent caries have no apparent upper

and lower demarcating borders

Radiopaque zone beneath amalgam It is shown that, with time, tin and zinc

ions from amalgam are released into the underlying demineralized dentine producing a radiopaque zone within the dentine

This may make the normal dentine on either side appear to be more radiolucent by contrast that may simulate the radiolucent shadows of caries and lead to difficulties in diagnosis

Limitations of radiographic diagnosis of caries Carious lesions are usually larger clinically

than they appear radiographically and very early lesions are not evident at all

Technique variations in film and X-ray beam positions can affect considerably the image of the carious lesion

Limitations of radiographic diagnosis of caries Exposure factors can have a marked effect on the

overall radiographic contrast and thus affect the appearance or size of carious lesions on the radiograph

Superimposition and a two-dimensional image mean that the following features cannot always be determined

Limitations of radiographic diagnosis of caries

Radiographic assesment of restoration The type and radiodensity of the restorative material, e.g.

— amalgam— cast metal— tooth-coloured materials such as composite or

glass ionomer Overcontouring Overhanging ledges Undercontouring Negative or reverse ledges Presence of contact points Adaptation of the restorative material to the base of the cavity Marginal fit of cast restorations Presence of absence of a lining material Radiodensity of the lining material.

Assessment of the underlying tooth Recurrent caries Residual caries Radiopaque shadow of released tin and

zinc ions Size of the pulp chamber Internal resorption Presence of root-filling material in the

pulp chamber Presence and position of pins or posts.

Limitation of radiographic image Technique variations in X-ray tubeheadposition may cause recurrent carious lesions to be obscured

Limitation of radiographic image Cervical burn-out shadows tend to be more obvious

when their upper borders are demarcated by dense white restorations because of the increased contrast differences

Superimposition and a two-dimensional image

Periodontal disease Most common of this are gingivitis and

periodontitis Radiograph aid the clinician in identifying

the extent of alveolar bone destruction, local contributing factors, and features of periodontium that influence prognosis

It should be combined with clinical examination to ensure a complete diagnosis reached

Radiographic assessment of periodontal condition Amount of bone present Condition of the alveolar crests Bone loss in the furcation areas Width of the periodontal ligament space Local initiating factors that cause or intensify periodontal disease Calculus Poorly contoured or overextended restorations Root length and morphology and the crown-to-root ratio Anatomic considerations Position of the maxillary sinus in relation to a periodontal deformity Missing, supernumerary, or impacted teeth Pathologic considerations Caries Periapical lesions Root resorptions

Radiographic features of healthy periodontium

Periodontitis Superficial inflammation in the gingiva

tissues extends into the underlying alveolar bone and there has been loss of attachment

Terms to use to describe various appearance of bone destruction include:

Horizontal bone loss Vertical bone loss Furcation involvement

Diagrams illustrating various radiographic appearance of periodontitis

Mild adult peridontitis

Moderate adult periodontitis Increase in the radiolucency of the tooth

root near alveolar crest Overall pattern of bone loss may appear

as generalized horizontal erosion of bone in a region or as localized vertical defects involving just one or two teeth

Horizontal bone loss Used to described loss of height of

alveolar bone around multiple teeth Extent of bone loss evident at single

examination does not indicate the current activity of disease.

Vertical osseous defects

Types of bony lesions that are localized to one or two teeth

Can be divided into 2 primary types which are interproximal crater and infrabony defects

Severe adult peridontitis Bone loss is so extensive that remaining

teeth show excessive mobility & drifting and are in jeopardy of being loss due to inadequate support

Osseous deformities in the furcation of multirooted teeth Furcation defects involve maxillary

molars 3x more often than mandibular molar

Dental condition associated with periodontal disease Occlusal trauma Tooth mobility Open contacts Local irritating factor

Occlusal trauma

Due to occlusal pressures are greater than physiologic tolerances of tooth’s supporting tissues

Assc with clinical symptoms such as increased mobility, wear facets and etc

Radiographic evidence- widening of PDL space and lamina dura, bone loss and increase in the number and size of trabeculae

Sequale of trauma include hypercementosis and root fracture

Does not cause gingivitis or periodontitis, but affect the epithelial attachment, or lead to pocket formation

Tooth mobility Widening of PDL space may suggest it It is due to resorption of both the root

and alveolar bone

Open contacts Trapped food may damage soft tissues

and induce an inflammatory response leading to periodontal disease

Thus bone loss detected

Local irritating factor Calculus deposits prevent effective cleansing

of a sulcus and lead to progression of periodontal disease

Defective restoration with overhanging or poorly contoured margin may lead to bacterial accumulation and periodontal disease

Trauma from tissues- surgical removal of impacted 3rd molar

Insufficient contour crown fail to protect gingiva

Evaluation of periodontal therapy Clinical crown to tooth ratio is a useful criterion

not only for determining the nature of restorative treatment to be performed on a tooth but also for deciding a prognosis of an individual tooth

It is a measure of tooth’s bony support, relating to proportion of clinical crown to bony investment

Unfavorable ratio when the length of tooth out of bone exceeds the length of root supported by bone

Effects of systemic disease on periodontal disease AIDS-characterized by a rapid progression that lead to bone sequestration and loss of several teeth Diabetes melitus -uncontrolled diabetes and periodontal disease patient show more severe and rapid alveolar bone resorption and more prone to develop periodontal abscess

The end . Thank youQ&A sessions now.

References Whaites, E. (2002). Essentials of dental

radiography and radiology. churchill livingstone.

White, S. C. (2000). Oral Radiology . Principles and Interpretation. Toronto, Canada: Mosby.