Endodontic Radiographs

Question 1

Describe the purpose of radiographs:

Answer 1

• Establish initial diagnosis (apical pathology)
• Provide information about tooth anatomy (Pulp chamber, root morphology, root curve, apical morphology)
• Determine working length
• Assess quality of instrumentation and obturation.

Question 2

What is “lamina dura”

Answer 2

Layer of compact bone forming the wall of a tooth socket.

Question 3

Describe ‘lamina dura’ in terms of endodontic radiographs

Answer 3

• Well-defined radiopacity that surround tooth root.

- Discontinuation or change in width of lamina dura indicates pathology.

Question 4

Define periapical radiolucency (PARL)

Answer 4

Radiolucency surrounding apex of tooth root.

Question 5

Describe periapical radiolucency (PARL) in endodontic radiographs

Answer 5

• Bacteria in root canal release toxin out of apical foramen.
• Inflammatory reaction of apical tissue.

Question 6

Pre-op periapical radiograph

Answer 6

• Always take immediately before treatment
• Take periapical radiograph -> best to use PARALLEL technique: need to make sure that there is no elongation or foreshortening
• Include adjacent teeth and >2mm of apical bone
• Use two angles for localization - direct + tube-shift

Question 7

Tube localization -SLOB rule

Answer 7

SLOB = Same lingual: Opposite Buccal

Question 8

SLOB explanation

Answer 8

• If object moves in same direction as the tube-head, the object is lingual
• If object moves in the opposite direction as tube-head, the object is buccal

Question 9

Reason for tube localization

Answer 9

• Identify superimposed canals and structures

- Identify curvature of canals