P1-ENDO LAB-RADIOGRAPHY

Enamel

most radiopaque structure.

Dentin

Uniform in density

burn-ou apperance araoun enamo-dentinal junction

mistaken for caries

cementum

Cannot be seen radiographically

cancellous bone

The bony trabeculae have a coarser

pattern in the mandible and tend to run

horizontally. Compare with the finer

lace-like pattern found in the maxilla.

periodontal ligament

periodontal ligament space on the radiograph.

It should be narrow and even around the whole of the root surface that lies

within the bone.

pathology

Any definite widening of the PDL space suggests the presence

of

lamina dura

radiographic artifact and it would be unwise to place to critical an interpretation on the variation in its appearance in diagnosis.

pulp chamber and larger canals

readily visible on the radiograph,

finer canals

disto-buccal canal of the maxillary first molar may be more difficult to see.

pulp stones

are evident in both molar teeth.

present few problems and their removal is easy from the chamber, although if they become lodged in a root canal they can present difficulties.

median suture of maxilla

appears a radiolucent line between the central incisors.

anterior nasal spine

appears as a V- shaped radiopacity which lies above or is superimposed on the incisive foramen.

nasal septum

separates the two nasal fossae and is seen as a radiopaque white line.

nose line

definite line across the radiograph.

lip line

A similar line in both upper and lower anterior radiographs

maxillary antrum

extend from the premolars to the tuberosity.

may be oculated giving the appearance of a cyst.

apices of the second premolar and first molar

lie close to or in the antrum.

incisive foramen

The radiolucent circular shadow may be superimposed over the apex of a central incisor and so be mistaken for a periapical lesion.

mandibular canal

runs from the mandibular foramen in the ramus to the mental foramen.

It is seen as a radiolucent band and may lie in close association with the apices of molar and second premolar teeth.

inferior dental canal

other term for mandibular canal

mental foramen

located below and distal to the apex of the first premolar.

mistaken for a pathological lesion when it appears close to the apex of one of the premolars, which is due to the angle at which the radiograph is taken.

lingual foramen

In radiographs of the lower incisor area the____ may be seen as white radiopaque area with a small central radiolucent dot.

nutrient canal

contain blood vessels supplying the bone and occur in both mandible and maxilla

lies between the central and lateral incisors as a vertical radiolucent line.

Periapical areas

The most common radiolucency found in the jaws is associated with the apices of the teeth. It is important in endodontics to be able to interpret early bony changes resulting from pulpal pathology.

rapid bone loss

Perforations of the lateral wall of the root or furcation will cause

Condensing osteitis

This is not a radiolucency and may not be of dental origin.

Condensing osteitis

is a radiopacity which occurs as a response to some form of injury such as low grade infection or excessive physical stress.

Condensing osteitis

The condition is symptomless. Characteristically it is not as radiopaque as enamel.

Advanced periodontal disease

will produce bony pockets on the radiograph.

pocketing

In this case the teeth were vital and the lateral bone loss due to .

round radiolucent area superimposed over the apex of a single standing maxillary premolar.

Radiograph of advanced periodontal disease

Cementoma stage one.

Early cementomas present as radiolucent areas, often around the apices of mandibular incisors. They progress over a period of about six years to radiopaque areas. The teeth remain vital to the pulp test and no treatment is required.

Cementoma stage two.

The radiopacity associated with the mesial aspect of lower right first molar is typical of a cementoma stage two. The tooth is vital and the PDL space is continuous around tooth roots.

Cementomas

are symptomless and harmless, and so require no treatment.

bisecting angle

parelling techniques

methods of taking periapical radiographs

bisecting angle technique

film is positioned close to lingual or palatal surface of the tooth and xray cone is directed at right angles to a line bisecting the plane of the film and long axis of the tooth

paralleling technique

The film is positioned in the mouth parallel to the long axis of the tooth.

paralleling technique in maxillary

To achieve this in the maxillary arch the film must be held away from the tooth.

x-ray cone

In the paralleling technique the it is then directed along a line at right angles to the film.

x-ray tube

In paralleling technique this must be positioned further from the patient than in the bisecting angle technique to reduce the magnification of the image by allowing only the more parallel x-rays to reach the fill.

extended cone

In paralleling technique it is often used to help direct the x-ray beam accurately and it is this which has given rise to the term long cone, which incorrect.

quick and easy to use

easy and comfortable to the patient

used in all mouths

siple to use iwth rubber dam in place

no additional equipment required

advantages of bisecting technique

produce distored radiograph

aygomagtic arch frequenty superimposed over apices of maxillary molar teeth

difficult to reproduce a radiograph on recall for comparison

partial image by coning off

difficult to take same tooth from different angles withouth severe distortion

disadvantages of bisecting technique

easy quick and produces more reliable results

distortion free

easily reproducible mandatory for comparing periapical radiolouncies and bone levels on recall

coning off is unlinely to occur providing localising ring used

simple and useful to view tooth undistorted from several angles

advantages of paralleling technique

uncomfortable to the patient

difficult to take in small mouths or with shallow flattened plates

difficult to take with rubber dam

apices lie below zygomatic arch on radiograph

film holder requires

disadvantages of parallelingtechnique

TRUE

TRUE/ FALSE

Radiation dose is similar for both techniques