maxillofacial radiology

Question 1

normal varieant

Answer 1

• an atypical finding that is seen in a % of the population which generally has no clinical significance

Question 2

dense bony islands

Answer 2

found in md. (normal variation)
- close to apices of premolars or molars
- well defined radiopacites
- 1cm in size
- can have spiky periphery
- often in a periapical relationship with the mandibular dentiton
(compact bone inside the marrow spaces in mandible)

Question 3

when can caries be detected radiographyically

Answer 3

30-40% demineralisation

Question 4

interproxiaml caries identified as

Answer 4

enamel caries seen as triagular radiuolucneyc

apex towards aDJ

Question 5

occulsal caries indentification

Answer 5

radiolucent line at ADJ with intact enamel can be indication

as lesion progresses becomes easier to detect

Question 6

cervical burnout

Answer 6

• due to geometry of the tooth can still mimic root caries
• in cervical burnout there is still an image of the root edge and is in tact
• stops at level of alveolar crest, not sub crestally
• buccal to lingual there is a curve interproximally

Question 7

recurrent caries

Answer 7

• appears as a zone of increased radiolucency along the margins of a restoration
• radiopaque materials such as metals can obscure recurrent caries and radiolucent lining materials can make detection difficult
• sometimes can be a radiolucent lining materail above the restorative material

Question 8

radiograph signs of periapical periodontitis

Answer 8

• earliest sign is widening of the apical periodontal ligament, followed by loss of lamina dura
• white arrows at lamina dura around socket of lateral incisor (compact bone which anchors the PDL space fibres as they insert into alveolar)
• Next to lamina dura is a thin radiolucent line (normal periodontal ligament space), usually about 0.1-0.2 mm wide (black arrows, normal periodontal spcace, shpuld be normal throughout)

Question 9

what can further be found radiographically as inflammation caries on from PDD

Answer 9

1) mainly bone resorption(rarefying osteitis)
- dissolution of bone
- increased radioluncey around the apex of a non vital tooth
- left lateral and central incisor
2) or mainly bone formation (Sclerosing osteitis)
- bone formation in an attempt of healing
- rare
- usually round at roots of lower molars in young patients
- area of increased bony density around apices of non vital tooth
- lower left 1st molar, repsonce to low grade chronic infection
- some dissolution but mainly scleorosing

Question 10

periodical granuloma and how it appears on radiograph

Answer 10

formation of granulation tissue is stimulated in an attempt to heal from chronic apical periodontitis
- appears as a well define radiolucency surrounding the apex of a non vital tooth (more radiolucent than bone)

Question 11

radicular cyst

Answer 11

lesion more than 1cm in diameter with a corticated (white) margin is probably a radicular cyst
- usually apical lucnecy is less than a 1cm periapical granuloma

Question 12

sequelae of periodical peritonitis

Answer 12

Root resorption 
-	roots of tooth absorbed by cells called odontoclasts (specific to tooth)
-	
Radicular cyst formation
-	untreated granuloma can form a cyst
-	at apex of non vital tooth
-	has a white margin
-	diameter bigger than 1cm

Ossteomyelitis

• infection of marrow spaces in the mandible
• many small radiolucencies throughout it
• needs antibiotics to irradicate it
• can have serious conequences if not treated

Question 13

horizontal boneloss

Answer 13

radiographic appearance when loss of alveolar bone occurs parallel to the occlusal plane

Question 14

vertical bone loss

Answer 14

• bone loss that is typically restricted to one tooth that extends along the length of the tooth root

Question 15

extent of bone loss staging

Answer 15

1) Mild stage (stage 1)
- less than 15% bone loss or less than 2mm

2) Moderate (Stage II)
- coronal 1/3 root
- horizontal bone loss in the 1st image
3) severe stage III
- middle 1/3 root
4) Stage IV very severe
- apical 1/3 root

Question 16

interdental craters

Answer 16

A two walled trough (bone loss) interdentally between the buccal and lingual cortices

• periodontal picket is deeper in the middle of the alveolus than it is at either the buccal or lingual martins
• appears as a low density band of bone at the alveolar crest
• with periodontal probe, deeper in the alveolus than at either buccal or lingual marings

Question 17

buccal or lingual cortex loss

Answer 17

Appears as two separate white lines with more lucenecy of the adjacent root
- impossible to tell which of the white lines represents the buccal plate and which represents the lingual plate

Question 18

periodontal endo lesions

Answer 18

Combination of apical infection and periodontal disease at the same tooth or one mimicking the other

Question 19

tooth structure abnormalities and what are they

Answer 19

• dens in dente (infolding of the outer surface of a tooth into the interior, at crown, at cingulum there is an infolding of the enamel and dentine into the pulp chamber, usually become non vital)
• dilaceration (sharp bend/90degree in the crown/root direction, can be due to previous trauma to a deciduous tooth, fold is the thin lateral line)
• taurodontism (enlarged pulp chambers, short roots (cow teeth) usually of no clinical significance, usually in people with syndromes)

Question 20

dentinogenesi imperfect can lead to

Answer 20

• can have short roots bulbus crowns

- can lead to obliteration of pulp chambers

Question 21

odontomes

Answer 21

• hamartoma (abnormal formation of normal tissue) forming dental hard tissues, compound or complex

Question 22

types of odontomes

Answer 22

1) compound
- lots of small denticles in a capsule and often occurs in the anterior maxilla
- insicor canine region
- often stops the eruption of permanent teeth, therefore can see if they have not erupted at the correct time
2) complex
- amorphous solid mass of calcified tissue that usually occurs in the posterior mandible