Endodontics
Course Review
Enoch Ng, DDS 2014
Radiographic Techniques
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Paralleling technique
o
Best definition and reproducibility, least distortion
o
Object and film parallel and central beam passes through them perpendicularly
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Angle bisecting technique
o
Harder to reproduce, some distortion, more superimposition of anatomic structures
o
Film placed directly against tooth without bending film
o
Central beam directed perpendicularly to imaginary line bisecting angle between tooth and film
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Film holders
o
Diagnostic radiographs – XCP instruments
o
Treatment radiographs – hemostat
Film placement is easier
Hemostat aids in cone alignment
Film held securely in place, less likely to slip
Always place “dot” on film to coronal part of tooth (won’t impose over roots)
Endodontic Radiography Limitations
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Radiographs give 2D shadows of 3D objects – require off angle radiographs to see 3
rd
dimension
o
Maxillary anteriors do NOT require off angle radiographs (only 1 canal)
o
Varying horizontal angulation allows for appreciation of 3
rd
dimension
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Vertical angulation
o
Increasing causes foreshortening of images
o
Decreasing causes enlongation of images
Radiographic Sequence
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2 diagnostic/pre-Op radiographs
o
1 straight on and 1 off angled (except Mx anteriors)
o
Bitewings should be taken if there is extensive decay/questionable restorability
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1 working length radiograph
o
If adjustment needed is >1mm, take new radiograph
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1 MAF radiograph
o
Has largest working length file used at corrected working length inside canal
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1 Master Cone radiograph
o
If adjustment needed is >1mm, take new radiograph
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1 Pre-sear radiograph
o
Check for dense fill and no voids
o
Last chance to make changes prior to sear off
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2 Post-op radiographs
o
1 straight on and 1 off angled to evaluate treatment
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For Mx anteriors, a 6 mount is used (only 1 pre-op and 1 post-op)
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For all other teeth, an 8 mouth is used
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Radiographs are mounted left to right before starting next row
o
Radiographs are mounted in descending order of list above
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Date each individual radiograph