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SeminarPrinciples of radiographic
interpretations
Introduction
• Interpretation: an explanations• Radiographic interpretation is an explanation
of what is viewed on dental radiograph
• Diagnosis: the identification of a disease by examination or analysis.
Aim:
• systematic method of image analysis
ACQUIRING APPROPRIATE DIAGNOSTIC IMAGES• Quality of the Diagnostic Image• Number and Type of Available Images
• VIEWING CONDITIONS:.Ambient light in the viewing room should be reduced..Intraoral radiographs should be mounted in a film holder..Light from the view box should be of equal intensity across
the viewing surface..The size of the view box should accommodate the size of the
film. If the viewing area is larger than the film, an opaque mask should be used to eliminate all light from around the periphery of the film. This mask can be fabricated from a sheet of opaque material cut to fit the entire view box, leaving an opening for one film.
.An intense light source is essential for evaluating dark regions of the film.
.A magnifying glass allows detailed examination of small regions of the film.
A. Wardray viewing box incorporating an additional central bright-light source for viewing over-exposed dark films.
B. The SDI X-ray reader — an extraneous light excluding intraoral film viewer with built-in magnification.
Image analysis• INTRAORAL IMAGES1. IOPA before bitewing2. Rt. Maxilla lft. Maxilla lft. Mandible rt.
Mandible3. Identify the anatomic structure, examine the
bone & character of the trabecular bone. 4. Compare the same area on adjacent and
corresponding areas of other side.
• 2nd visual circuit1. Examining the ht. and cortication of alveolar
bone relative to teeth.2. Examine alveolar bone for extent and
severity of bone loss3. Areas of erosion; difference in trabeculae
pattern
• 3rd visual circuit1. dentition and associated structures2. Each tooth in sequence, using all available
images3. Examine PDL space & lamina dura of each
tooth.
EXTRAORAL RADIOGRAPHY• Analysis of Intraosseous Lesions1. picture matching, or "Aunt Minnie,"method2. step-by-step analysis
step-by-step analysis
STEP 1: LOCALIZE THE ABNORMALITY
location
localizedunilateral
bilateral
generalized Metabolic/ endocrinal
cherubism
• Position in the jaws Soft tissue
Within jaws• Odontogenic originCoronal to tooth• Odontogenic originAbove IAC• Neural or vascular originWithin IAC• Not of odontogenic originBelow IAC• Cartilagenous or osteochondromasCondylar region
Specific epicenters
CGCG •Mandible- anterior to 1st molar•Maxilla- anterior to cuspid
Osteomyelitis •Mandible more common
Periapical cemental dysplasia
•Periapical region of teeth
• Single or multifocal periapical cementa! dysplasia, odontogenic keratocysts, metastatic lesions, multiple
myeloma, leukemic infiltrates
• Size- may aid in the differential diagnosis
STEP 2: ASSESS THE PERIPHERY AND SHAPEWell defined
borders
Punched out
sclerotic margin
radiopaque lesion with radiolucent
margins
corticated margin
Ill defined borders
blending border
invasive border/ p ermeative
• Shape
Circular/ hydraulic cyst
Scalloped/ multilocular
Cyst, cystlike lesions, tumors
STEP 3: ANALYZE THE INTERNAL STRUCTUREradiolucent
mixed
radiopaque
Radiolucent lesions:Unilocular- eriapical cyst, granuloma,, abscess, PA cemental dysplasia.
Multilocular- OKC, CGCG, botryoid odntogenic cyst, aneursymal bone cyst,cherubism
Moth eaten - osteomyelitis, osteosarcoma, lymphoma,multiple myeloma
radiopaque lesions:Focal opacity- PA cemental dysplasia, condensing osteitis,sclerotic bone
Target lesions- benign cementoblastoma, complex odontome
Multifocal confluent- osteitis deformans, florid osseous dysplasia
Mixed- AOT, CEOT, compound odontome, KCOT, ossifying fibroma
Irregular- osteosarcoma, chondrosarcomaGround glass- FD, ostetis deformans, osteopetrosis, hyperthyroidism
STEP 4: ANALYZE THE EFFECTS OF THELESION ON SURROUNDING STRUCTURES
•stimulate bone resorption or formation.Inflammatory
lesion
•slowly creates its own space by displacing teeth and other surrounding structuresspace-
occupying
Epicentre above the crown
Apical displacement of tooth eg; follicular cyst, odontomas
Epicentre in ramus push teeth in an anterior direction eg; cherubism
Papilla of developing teeth
push the developing tooth in a coronal direction eg; lymphoma, leukemia, Langerhans‘ cell histiocytosis
Widening of the periodontal membrane space
Malignant lesions; an irregular widening and destruction of the lamina dura
Resorption of teethchronic or slowly growing process; more commonly related to benign processes
Presence of reactive bone at periphery
slow, benign growth and possibly the ability to stimulate osteoblastic activity in the surrounding bone
IAN canal superior displacement Fibrous dysplasia
IAN canal widening with cortical boundary
benign lesion of vascular or neural origin
IAN canal widening with cortical destruction
malignant neoplasm growing down the length of the canal
•Periosteal new bone formationSlow growing lesion
•Missing of cortical plateRapidly growing lesions
•Lift the periosteum•Recurrence cause onion skin
patternInflammatory lesion with exudation
STEP 5: FORMULATE A RADIOGRAPHICINTERPRETATION
Decision 1
Decision 2
Decision 3
Systematic approach
• The entire radiograph• Specific lesions
The entire radiograph
Specific lesions
A systematic description of a lesion should include its:• Site or anatomical position• Size• Shape• Outline/edge or periphery• Relative radiodensity and internal structure• Effect on adjacent surrounding structures• Time present, if known.
references
• White & Pharoh Oral Radiology,4th Edition• White & Pharoh Oral Radiology, 5th Edition• Eric Whaites ; Essentials Of Dental
Radiography & Radiology, 3rd Edition• Karjodhkar; Textbook Of Dental & Maxillofacial
Radiology 2nd Edition• Dental Radiography Principles And
Techniques; Haring & Howerton, 3rd Edition