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
A distal cone shift will result in the M-buccal canal appearing to shift to the ______ and the M-lingual canal will appear to be ______ to it.
mesial
distal
How do you know if a radiograph is a straight on shot versus a shift shot?
straight on you can see contacts
___% of the time a lower mandibular premolar has 2 canals
24
- this is called a fast break
What happens to the ML and MB canals in a straight on x-ray?
ML and MB superimposed
If you shift a beam mesial on mandibular molar what happens?
ML & DL canals now appear to be mesial to buccal canal and moving TOWARD the cone & the MB & DB canals move AWAY FROM the cone toward the distal
XR shifted to the Distal may separate the ______ canals better than M shift
mesial
If you get confused with shift shots, you may end up further shortening the canal that is already…
TOO SHORT
The _______ canal moves to the mesial on a mesial shift shot.
lingual
mandibular premolar
maxillary molar
What are the common periapical lesions of endodontic origin (LEOs)?
- Thickened PDL
- P/A Radiolucency
- Root Fractures
If you see a thickening of the PDL on a radiograph this does or does not PROVE it is a LEO?
DOES NOT
Is this radiograph diagnostic?
The radiograph is NOT DIAGNOSTIC as the crown is NOT shown and we have no idea if the etiology is a LEO (e.g. caries) or merely thickening arising from traumatic occlusion or recent trauma
We must employ: Diagnostic XRs, History, Clinical Examination, and Clinical & Sensibility Testing to arrive at an _________
ETIOLOGY
With no medical or dental history nor clinical findings to the contrary we can be relatively secure in our justification of a LEO in this case based on…
pulp testing and apparent depth of injury from caries
A radiolucency of endodontic origin is often BUT not always associated with a pulpal DX of ___________
necrotic pulp
The lesion does NOT move away from the apex when the XR angulation is changed; therefore associated with the _______
tooth
Can you diagnosis an abscess versus granuloma versus cyst from a radiograph?
- It is NOT possible to accurately diagnose these conditions radiograph.
- a BIOPSY may be taken
VRF often is or is not seen on standard dental XR
is not
What types of differential diagnosis are required for pathoses of endodontic origin?
- Anatomical Landmark?
- Radiographic Artifact?
- Another (non-endodontic lesion)?
- Oral Manifestation of Systemic
Disease?
A distinguishing characteristic of a radiographic lesion of endodonticpathosis (LEO) is that the radiolucency stays at the _____ regardless of coneangulation.
apex
Can YOU tell the LEOs from normal anatomy or systemic pathology?
it is a mistake to diagnose primarily from the radiograph as Differential Diagnosis must be made on a logical basis as supported by evidence beyond the appearance of the radiographic image itself.
It is or is not true that ALL “periapical radiolucencies” that will be presented radiographically are, in fact, LEOs?
Is not true
What is a differential diagnosis for common anatomical landmarks?
- Maxillary Sinus
- Nasal Cavities
- Incisive Canal
- Mental foramen
- Mandibular Depression (Concavity)
M– maxillary tuberosity
L– zygomatic process
H– maxillary sinus
J & K–Bony septum of Maxillary sinus
I- Floor of Maxillary sinus
The ____________ is often superimposed on maxillary posterior apices. Do not be fooled!
Maxillary sinus
You should see the ____ space distinctly uniform width and un-interrupted.
PDL
The _____________ are often superimposed on the central and lateral apices
nasal cavities
A– Mandibular canal
B– Mental Foramen
C– Cortical bone
G– Border of Mandible
K– Lamina dura
M– Root canal Filling
If radiolucent area moves AWAY FROM the apex on multiple films, it is NOT associated with the apex and therefore is probably NOT a ________.
P/A lesion
We MUSTpulp test every tooth which we plan to ________
restore
What is the most common anatomical landmark confused with LEO?
mental foramen
Suspect all apparent bilateral lesions as being ___________________ and NOT of pulpal origin until proven otherwise.
anatomical or systemic
Green - outline of mandibular depression
Yellow - mental foramen
Red - lamina dura
Bilateral Lingual Concavities
What are examples of Non-endodontic radiolucencies which may mimic LEOs?
- Lateral Periodontal Cyst (abscess)
- PCOD
- FOD
- Hyper-parathyroidism
- Central giant cell granuloma
- Neoplasias
What are the symptoms of a lateral periodontal cyst (abscess)?
- May be asymptomatic OR: may mimic symptoms of SAP or AAA
(CC = pain, swelling, palpation +)
What is the etioloyg of a lateral periodontal cyst (abscess)?
infected perio. Pocket
– If it is able to drain =asymptomatic
– If unable to drain =symptomatic
What is another name for periapical cemental osseous dysplasia (PCOD)?
- “Cementoma”
- Periapical fibrous dysplasia
- Periapical cemental dysplasia
What are the characteristics of periapical cemental osseous dysplasia (PCOD)?
- All teeth were vital and asymptomatic
- Radiolucent vs radiopaque (mixed)
What is one of the more common radiolucencies that causes unneeded endo treatment?
periapical cemental osseous dysplasia (PCOD)
What stage of focal osseous dysplasia (FOD) is this?
Osteolytic stage
What stage of focal osseous dysplasia (FOD) is this?
Ossifying stage
What are the characteristics of hyper parathyroidism as a non endodontic lesion?
hyPERcalcemia
hyPOphosphatemia
“Brown’s Tumors”
What is a central giant cell granuloma?
- benign intraosseous lesion found in the anterior of the maxilla and the mandible in younger people
- It is characterized by large lesions that expand the cortical plate and can resorb roots and move teeth.
- It is composed of multi-nucleated giant cells.
- It has a slight predilection for
females.
What should you do if you suspect a central giant cell granuloma?
DON’T do ANYTHING except REFER to Oral Pathologist, Endodontist, Oral Surgeon, MD
What are the characteristics of metastatic breast CA (neoplasia)?
*Causes of roots “spiking” & resorption
*Poorly defined borders of lesion
*Loosening of teeth
*Pulps may still be vital
*Symptoms of neoplasia, esp in mandible—may be pain as well as paresthesia
*VIP lesion is usually ragged and asymmetrical!
What do you do for metastatic breast CA (neoplasia)?
*REFER STAT
- Careful review of Health History is essential. This is WHY we take the HH BEFORE anything is done.
It is ALWAYS NECESSARY to complete Examination and Clinical Testing to arrive at both a _______ and a __________ DX.
PULPAL
PERIRADICULAR
If you can’t make an accurate DX; you can do…
no treatment
What is a cone beam computed tomography?
Capable of essential creating multiple sections of an area to accurately display:
– Unusual or extra canals
– Location & Extent of cracks
– Aberrant anatomical features
– Otherwise unseen pathology
What type of radiography is becoming the standard of care in advanced endodontics?
cone beam computed tomography
Also, when doing a DX . . . Keep in mind that problems do not always occur as a _______ issue
single
