introduction to radiographic interpretation and caries on radiographs

Question 1

where to start?

Answer 1

Identifying permanent and deciduous teeth

ID developing and erupted permanent teeth first

• Molar teeth – 6 at 6s, 7 at 12, 8 at 18
• Takes 3 years for root

Question 2

age

Answer 2

permanent dentition - symmetrical

approx 18

Question 3

age

Answer 3

mixed dentition - late

• Molar teeth – 6 at 6s, 7 at 12, 8 at 18
  
  • Takes 3 years for root

Roughly 12-13 years

Question 4

age

Answer 4

mixed dentition - early

6 years old

3 longest distance to travel so above premolar

Question 5

what is different here

Answer 5

Supernumeray between central maxilla

Question 6

what is different here

Answer 6

Only one premolar in maxilla right (no 2nds), no upper left canine

Lower left E severe caries

No lower right 5

Question 7

common site for supernumeray and missing teeth

Answer 7

End of sets of teeth and midline common supernumeray and missing teeth ​

Question 8

clinical evaluation report for radiographs

Answer 8

• legal requirement
• clinical evaluation of the outcome of each exposure is (must be) recorded in accordance with the employer’s procedures
• for normal radiographs in GDH&S the responsibility is the Referrer’s
  
  • your patients – YOU
• complete in the patient’s written notes only
  
  • write everything from meeting and condense when presenting to clinician

Question 9

potential caries sites

Answer 9

• Pit and fissure
  
  • Occlusal
  • Buccal – may be confused radiographically with occlusal
• Smooth surface
  
  • Interproximal
  • Lingual – may be confused radiographically with occlusal and buccal
  • Root – may be confused with “cervical burnout”
• Secondary/recurrent – under restorations

Question 10

7 caries diagnosis methods

Answer 10

• Visual
  
  • Dry
• Radiography
  
  • Film
  • Digital
• Elective temporary tooth separation
• Fibreoptic transillumination
• Electrical methods
• Laser fluorescence
• Calcivis® - detects calcium ion loss from demineralising tooth surfaces

Question 11

locate caries and risk level

Female 15

previous restoration and other risk factors

Answer 11

caries 25M

high risk

Question 12

describe OPT of 7 year old female

Answer 12

Extensive caries in deciduous molars

Erupted 1^st molar

Problem with overlap on OPT so hard to detect caries

so take bitewings

• can see extensive caries 75M, 74D
  
  • impact on pulpal tissues

Question 13

describe features in periapical 36, 37, 38

Answer 13

• gross caries occlusal 38,
• enamel 37 mesial,
• dentine 36 distal

Question 14

caries progression shape

Answer 14

cone-shape:

• broad at surface,
• point deeper;
• lateral spread on reaching dentine

Question 15

how to ID caries easier on radiograph

Answer 15

adjust density and contrast on PACS to ID easier

Question 16

cervical burnout

Answer 16

• Phenomenon caused by relative lower X-ray absorption on the mesial or distal aspect of teeth, between the edge of the enamel and the adjacent crest of the alveolar ridge. Because of the relative diminished X-ray absorption, these areas appear relatively radiolucent with ill-defined margins. Cervical burnout out may mimic root surface caries.*
• Exposure dependent

Saucer shaped radiolucency, premolars and molars

Smooth margins on 6 restoration – cast gold

Question 17

secondary caries or deficient margins?

Answer 17

Sequelae of caries – circular of radiolucency at 22 root

Measure on radiograph bigger than real life (magnified in reality?)

Question 18

what affects radiolucency on dental radiographs

Answer 18

bucco-lingual dimension of teeth variable

• Structures to be traversed variable:
  
  • +/- enamel
  • +/- surrounding bone

Question 19

peridontal assessment - selection criteria recommendations

Answer 19

• Radiography secondary to clinical examination and full mouth periodontal assessment
• Pocketing 4-5 mm, horizontal bitewings
  
  • Long axis of image receptor goes horizontal
    
    • Not common in GDH
• Pocketing =>6 mm, vertical bitewings + periapicals if bone not shown
• Irregular – may supplement with periapicals
• Panoramic useful for overview of all teeth, supplemented by periapicals if required, or full periapicals
• Periapicals for suspected perio/endo leasions

Question 20

periodontal radiography

Answer 20

• If panoramic choose orthogonal projection (P4, button on machine)
• Beam angulation crucial
• Horizontal angle 90^o to line of arch
  
  • avoid overlaps of adjacent teeth, overlap = cannot see bone between teeth
• Vertical angle 90^o to long axis of tooth
• Pockets may be difficult to show – consider GP point
• Clinical pocket depth examination crucial

Check all radiographs as teeth overlap in different full mouth periapical

Question 21

describe some features

Answer 21

Crowns, root filling 21, lower left 7 and 8 wedge shape = food packing, lower right 6 radiolucency – bone loss after RCT

Check all radiographs as teeth overlap in different full mouth periapical