Diagnostic imaging is an integral part of the diagnostic process in clinical dentistry. Radiographs are often obtained as part of a complete examination. Appropriate radiographic interpretation is used along with clinical information and other tests to formulate a differential diagnosis. A radiograph is a two dimensional image of a three dimensional object.
Role of radiographs
- Clinical examination phase
- Diagnosis( confirm/exclude)
- Treatment planning
- During treatment
- Follow up
Guidelines for suggesting Dental Radiographs
- Its important to make radiographs only after a clinical examination.
- Order only radiographs that directly benefit the patient in diagnosis &treatment.
- Use the least amount of radiation exposure .
Clinical situations that need radiographic examinations
- Deep/ proximal Dental Caries
- Periodontal Diseases
- Dental Anomalies
- Growth&Development assessment
- Dental Malocclusion
- TMJ Disorders
- Implants
- Paranasal Sinuses
- Trauma
RADIOGRAPHIC INTERPRETATION depends on:
- Clinical examination.
- Quality of diagnostic image.
- Number &type of available images.
- Viewing conditions.
Step 1: Localize the abnormality
- Localized or generalized
- Position in the jaws
- Single or multifocal
- Size
Step 2: Assess the periphery &shape
- Is the periphery of lesion well defined or ill defined
- Shape of lesion
Step 3: Analyze the internal structure
- Air,Fat,or Gas
- Fluid
- Soft tissue
- Bone marrow
- Trabecular bone
- Cortical bone &dentine
- Enamel
- Metal
Step 4: Analyse the effects of the lesion on surrounding stuctures.
- Teeth,lamina dura,periodental membrane space.
- Inferior alveolar canal&mental foramen.
- Maxillary antrum.
- Surrounding bone density&trabecular pattern.
- Outer cortical bone&peiosteal reaction.
Viewing Conditions
- This should be done in a quiet, darkened room.
- At least two good, evenly-lit viewing boxes are required.
- A bright light illuminator is required for relatively over-exposed areas.
- Mounted in holder.
- Appropriate size of viewbox to accommodate film.
- Magnifying glass-detailed examination of small regions.
Routine assessment of radiographs
- Ensure that the radiograph is the one of the patient being examined, check the date, card number.
- Ensure two orthogonal projections are available.
- The radiographic views are named according to the direction the primary beam enters and leaves the tissue and the body part being examined.
- The position of the patient during exposure should be known, and left/right markers should be identified.
- The radiograph should be of high technical quality with respect to positioning, centring, collimation, exposure and development, and should be free from artefacts.
Article by Dr. Siri P. B.
