Endodontic Radiology Flashcards
What is a radiograph?
A static 2-dimensional shadow of a dynamic 3-dimensional situation
What two things do radiographs need to be?
diagnostic
current
If the roots of teeth do not look correct what can you try?
consider a better angulation
What does a diagnostic radiograph need to have?
Must be distinct and include all of the areas of concern in proper orientation without cone cuts, overlapping, elongation or foreshortening.
Optimization of image quality and relationship to the area of concern are paramount in helping to determine a correct _________
Diagnosis
Diagnostic endo radiographs must include all of the tooth and at least __ mm. apical to the end of the root.
5.0
All Posterior teeth REQUIRE __ P/A radiographs
2
(straight-on and 20 degree H. angled)
Always a good idea to take multiple ______ to help guess the 3-D anatomy
angles
What does a 5 year old sloppy X-ray tell you?
It should tell you to take current radiographs!
What is a current endo radiograph?
Current is 1-2 mos.
Drop-off perio pocket or a DST could indicate a new…
vertical root Fracture
Do Radiographs have Historical Value?
YES!
A SERIES of RADIOGRAPHS over time with similar angulation and exposure can be very helpful when following a new, developing or healing lesion.
What are the benfits of endodontic radiology?
- Suggests LEOs & other Pathosis
- May Indicate Unseen Canals & Proximal Anatomy
- Largely locates most curvatures
- Assists in Working-Length Determination
How do you determine which canal is which if there are multiple?
Changes of Horizontal Angulation = “SLOB” rule
Modern diagnostic digital radiography is without ____ when appropriate hygiene techniques are employed.
risk
What are the 3 biggest risks of endodontic radiology?
- Attempting to DIAGNOSE from RADIOGRAPHS ALONE
- Seeing something on the film that is NOT THERE
- FAILING to see something on the film that IS THERE
Unless you LIKE spending Time & money the Court deals with both:
ERRORS of COMMISSION
ERRORS of OMISSION
What issues in radiographs can lead to confusion and inaccurate interpretation?
- Artifacts
- Poor Resolution
- Wrong Angle
What are other detractors that can lead to an inaccurate diagnosis?
- Normal or Aberrant Anatomy
- Apparent LEO is another entity
- Oral manifestation of Systemic Disease Unexpected Occurrence
What root curvatures are more easily noticed: mesio-distal or buco-lingual?
Mesio-distal
Canals usually calcify in what direction?
coronal to apical
When you see a “Bullseye” on an image, you are seeing…
- a facial or lingual root tip “on end”.
You don’t know if it curves to the Facial or the Lingual (good opportunity to refer).
This 4th (Disto-Lingual) root in mandibular 1st molars is seen most frequently in ___________ populations.
Native American and Asian
Often in mandibular 1st molars the D-L root and canal curve sharply to the _______ to present a classic appearance.
facial
D-L root happens around ___% of the time
30%
If we place a file in a single canal at a known length, and radiograph it, we can thereby measure the…
length of the canal
What does measuring the length of the canal using a radiograph allow you to do?
adjust our file’s length to the desired length (WL) at which we want to do our work inside the tooth.
We want to work and fill at short of the canal exit ___ mm. in most cases.
1.0
What are the three ways to tell which canal is facial or lingual?
- You could take a separate XR of each canal with a single file in a known canal.
- You could place files of varying radiographic appearance in each of the canals and remember which file went in which canal.
- You could increase the vertical angle of the radiograph; the lingual canal would be longer, the buccal shorter.
What are the challenges with taking separate XR of each canal with a single file in a known canal?
- You would then need to label the X-rays carefully/correctly not to become confused
- Wastes TIME
What are the challenges with placing files of varying radiographic appearance in each of the canals?
- remember which file went in which
canal - Usually only 1 type of file available
What are the challenges with increasing the vertical angle of the radiograph?
However the true lengths would be grossly distorted & it would be virtually useless for accurate length determination.
You should take a straight-on radiograph and then a second radiograph with a 20º change in horizontal angulation as in taking a _______
“Shift-Shot”
What is the “SLOB rule”?
- Same Lingual, Opposite Buccal
- As the angle of the X-Ray cone is shifted, the object furthest from the XR cone (lingual) will move with the XR cone.
Lower molar XR cone shifted mesially… the M-buccal canal will appear to shift to the ______
distal
Lower molar XR cone shifted mesially… he M-lingual canal will now appear to have moved _______ to the facial canal.
mesially