VARIOUS TECHNIQUES IN ENDODONTICS

1. ENDODONTIC RADIOGRAPHY
BDS IV
20I8-2019

2. OUTLINE
 Introduction
 Importance
 Radiographic sequence
 Radiographic interpretation in endodontics
 Differential diagnosis
 Special techniques
 New technology

3. INTRODUCTION
 Radiographs are the ‘eyes’ of the dentist when performing many procedures.
 It is the shadow features produced by x-ray on radiographic film.
 Radiograph is a two dimensional shadow of a three dimensional object.
 Radiographs are indispensable, single diagnostic reliable method and prognostic aid that are
essential for diagnosis, treatment planning, and for monitoring endodontic treatment which are
not visible.

4. Types of Radiographs
Conventional radiographs
 Intraoral periapical radiograph
 Bitewing radiograph
 Occlusal radiographs
 Panoramic radiographs

5. IMPORTANCE OF RADIOGRAPHS IN ENDODONTICS
Radiographs are essential to all phases of endodontic therapy.
1. Diagnosis
2. Treatment
3. Recall/ follow-up.
DIAGNOSIS
 Helps in identifying pathosis i.e. pulpal, periapical, periodontal
 Determining the root and pulpal anatomy;
-no. of roots/ root canals.
-unusual root morphologies.

6. Cont..
-root curvatures
-canal locations with respect to chambers
-bifurcations/trifurcations.
-Calcifications.
 Characterizing normal structures.
-Helps in differentiating the normal from the abnormal structures.

7. Cont…
TREATMENT
 Determining working lengths
 Moving superimposed structures; Certain normal anatomic structures may superimpose on the
apices of the teeth. Changing the angulations helps in separating them.
 Locating canals i.e. Extra canals or missed canals.
 Differentiating canals and PDL spaces.

8. Cont…
 Evaluation of obturation; helps assess the quality of obturation by evaluating the;
-Length- if working length has been maintained, overfilling, under filling.
-Density- the radiopacity of the material.
-Taper of the preparation of the configuration.

9. Cont…
RECALL/FOLLOW-UP
 Most times the patient does not know the status of the root
canal treatment.
 In most cases, the patient may be asymptomatic, only
radiographs help in diagnosing the endodontic failure.
 There may be evidence of the development of new lesions;
periapical, periodontal, non-endodontic or evaluation of the
healing/ progress of treatment.

10. LIMITATIONS OF RADIOGRAPHS
 It can easily be distorted through improper technique, anatomical limitations or processing
errors.
 Buccal-lingual dimensions is absent on a single film.
 Various states of pulpal pathosis are indistinguishable.
 The bacterial status of hard or soft tissue is not detectable.
 Peri-radicular soft tissue lesions cannot be diagnosed accurately.
 Chronic inflammatory tissue cannot be distinguished from healed, fibrous scar tissue.

11. RADIOGRAPHIC SEQUENCE
-Radiographs are made in a recommended order and number for each procedure.
-There are 4 main types of radiographs taken during endodontic treatment;
 Pre-operative/Diagnostic radiograph
 Working radiograph
 Obturation
 Follow- up/ Recall

12. Cont…
Pre-operative radiograph
 The initial diagnostic radiograph is used primarily to;
 Detect pathosis and to provide general information on root and pulp anatomy.
 No. of exposure depends with the situation but mostly a single exposure is necessary.
 A properly positioned film and cone permits visualization of at least 3-4mm beyond the apex.

13. Cont…
During treatment
 Working length radiograph – taken to establish working length of canal & to
verify tooth anatomy (is with a small file inside the canal)
 During cleaning & shaping depending on how the treatment is progressing.
 With master file in place to confirm if its equivalent to WL & shapes of
canals are adequately tapered after the prep.
 With master cone placed in prepared canal . An accurate cone fit assures
that the tooth is properly prepared with an ideal tapered prep

14. Cont…
Obturation Radiographs
 Used to evaluate endodontic treatment.
 Important in evaluating obturation length and quality.
 Ideally paralleling angle technique should be used.
 Advisable to take 2 at different angulations for missed canals
Follow up radiographs
 To determine success of the therapy.
 Helps the dentist determine if the tooth has healed or is still in the healing process
 Helps determine if there are any signs of persistent infection

15. RADIOGRAPHIC INTERPRETATION
 Radiographic interpretation is not restricted to identification of a problem and the
establishment of a diagnosis but also a projection to treatment.
 In order to effectively use and understand x-rays here are a few tips.
 The apices of the roots must be completely visible.
 Each radiograph must include the entire area of interest, and the apices of the teeth must be
at least 3 mm away from the border of the radiograph.
 Take two or three radiographs at different angles.
iv) The long cone paralleling technique is the technique of choice for endodontic radiography

16. Radiograph interpretation
Caries
 In caries diagnosis, the endodontic dilemma is to determine the spatial relationship of carious
lesions to the pulp.
 Caries located on the buccal or lingual aspect may project over the pulp and give the false
impression of pulpal involvement.

17. Cont…
Pulp changes: Calcifications, obliterations
 Abnormal pulp calcification may be reactionary dentine to caries or trauma, degenerative
localized or diffuse calcifications in the coronal characteristically the radicular pulp
 Pulp obliterations following traumas such as; tooth concussion or luxation or intentional or
necessary replantation.

18. Cont…
Pulpal changes: Internal resorption
Internal resorptions are usually associated with the replacement of dentin by a soft tissue with
resorbing cells causing a balloon-shaped lesion starting from the radicular pulp. The radiographic
end result is around or ovoid radiolucent area.

19. Cont…
Fractures
 Fracture of a root can be difficult to diagnose but may result in reparative processes that
become recognizable in later radiographs.
 Diagnosis of root fractures may be made easier by using multiple
projections.

20. Cont….
Periapical lesions
 Apical periodontitis is typically a droplet-shaped radiolucent area associated with the root apex
surrounded by bone in continuity with the lamina dura at some distance from the pulpal exit
Normal Periradicular
tissue in a vital tooth
with symptomatic
apical periodontitis
after the placement of
a deep restoration
with abnormal
occlusal contacts

21. DIFFERENTIAL DIAGNOSIS
-This can be according to relation of the lesion to other structures &
anatomic landmarks.
Endodontic pathosis-radiolucent
-Distinguishing characteristics which aid in differentiating radiolucent
lesions of endodontic from non- endodontic pathosis;
 The apical/ radicular lamina dura is absent, having been resorbed.
 A ‘hanging drop of oil’ shape is characteristic of the radiolucency.
 The radiolucency stays at the apex regardless of cone angulation.
 A cause of pulpal necrosis is usually evident.

22. Cont…
 If radiolucency is above the inferior alveolar nerve canal, the likelihood is greater that it is
odontogenic in origin.
 If it is below IAC it is unlikely to be odontogenic in origin.
 If it is within the IAC, the tissues of origin is probably neural or vascular in nature.

23. Cont…
Endodontic pathosis- radiopaque
 Are better known as condensing osteitis. Such lesions have an opaque, diffuse appearance and
histologically, they represent an increase in trabecular bone.
 Radiographic pattern is one of diffuse borders and a roughly concentric arrangement around the
apex.
 Pulpal necrosis and radiolucent inflammatory lesions may or may not be present.

24. Cont…
Characteristics of apical radiolucency
strongly suggest endodontic pathosis.
Lamina dura is not present, and the lesion
has a “hanging drop of oil” appearance. The
cause of pulpal necrosis is also evident.
Condensing osteitis. There is
diffuseness and a concentric
arrangement of increased
trabeculation around the apex. Close
inspection shows a radiolucent lesion
at the apices also.

25. Cont…
 Frequently, condensing osteitis and apical periodontitis are present together.
 Pulp is often vital and inflamed.
Non- odontogenic pathosis
Radiolucent lesions
 They are varied but infrequent.
 Pulp tests provide the cardinal differentiation. Non endodontic lesions are associated with a
responsive tooth i.e. CGCG

26. Cont…
Radiopaque lesions
 Frequently interpretive errors are made in identifying radiopaque structures located in the
apical region of the mandibular posterior teeth.
 Unlike condensing osteitis, these are not pathologic and can have a more well defined border
and a homogenous structure.
 They are not associated with pulpal pathosis
 Example, Osteoma.

27. Cont…
Anatomic structures
 Several anatomic entities are superimposed on or may be confused with endodontic pathosis.
Mandible
 Classic example of radiolucency that may outlie an apex is the mental foramen over a
mandibular premolar.
 This is easily identified by noting the movement on angled radiograph and by identifying the
lamina dura.

28. Cont…
Enostosis (or sclerotic bone) is
represented by the dense,
homogeneous, defined
radiopacity. This is not pathosis
Radiolucent area over the apex could be mistaken
for pathosis. B, Pulp testing (vital response) and a
more distal angulation show the radiolucency to be
a buccally placed (SLOB rule) mental foramen

29. Cont…
Maxilla
 Maxilla region contains several structures that may be confused with endodontic pathosis e.g.
 Maxillary sinus, incisive canals, nasal fossa, zygomatic process, anterior nasal spine.
 Characteristics of the structures and pulp responsiveness to test are important differentiations.

30. SPECIAL TECHNIQUES
Paralleling technique
 Dental films must be placed parallel to the long axis of the tooth to be examined.
 The central ray is directed at a right angle to the tooth and the film.
 Is best due to;
 least distortion & more clarity
 Reproducibility of film and cone replacement

31. Cont…
Radiographic parallelism. The long axis
of the film, the long axis of the tooth, and
the leading edge of the cone are parallel
and perpendicular to the X-ray central
beam.

32. Cont…
Bisecting technique
 The film is placed against the tooth as straight as possible
 There is an angle between the x-ray film and long axis of the
tooth.
 The central x-ray beam is directed perpendicular to an
imaginary line which bisects the angle between the plane of
the film and the long axis of the tooth.
 Elongations is produced by too flat angulations while
foreshortening is produced by too acute angulation.
 Can be used in case of;
 Low palatal vault
 Exceptionally long roots
 Maxillary tori

33. Cont…
Bitewing projections
 Useful especially for dx of proximal caries
 Can be useful as a supplemental film, normally has less image distortion
because of its parallel placement, and it provides critical information on
the anatomic crown of the tooth.
 This information includes the anatomic extent of the pulp chamber, the
existence of pulp stones or calcifications, recurrent decay, the depth of
existing restorations, and any evidence of previous pulp therapy.
 It indicates the relationship of remaining tooth structure relative to the
crestal height of bone. Thus it can aid in determining the restorability of
the tooth

34. Cont…
Cone shift technique
 The main concept of technique is that as the vertical or
horizontal angulations of X-ray tube head changes, the object
buccal or closest to the tube head moves to opposite side of
radiograph when compared to lingual object
 Used to identify the spatial relation of an object.
 Other names for this procedure are the buccal-object rule,
Clark's rule, and the SLOB (same lingual, opposite buccal)
rule.
 Helps to locate additional canals or roots, to distinguish
between objects that have been superimposed, and to
distinguish between various types of resorption.

35. Cont…
A, Right-angle horizontal projection superimposes
four files, one on the other. B, Horizontal variance of
30 degrees separates four canals.

36. Cont…
 It also helps the clinician to determine the
bucco-lingual position of fractures and
perforative defects, to locate foreign
bodies, and to locate anatomic landmarks in
relation to the root apex.

37. NEW TECHNOLOGY
Digital radiography
 The digital system relies on an electronic detection of an x-ray generated image that is
electronically processed on a computer screen.
ADVANTAGES
 Reduced exposure to radiation
 Increased speed of obtaining the image
 Storage as a digital data in computers
 Possibility for digital enhancement.
 Ease of transmissibility
 Elimination of manual processing steps.

38. Cont…
Disadvantages
 High initial investment cost.
 Issues related to infection control as the detectors cannot be autoclaved.
 Competency using the software may take time to master.

39. Cont…
Cone Beam Computed Tomography
 It’s a diagnostic imaging modality that provides high quality, accurate three- dimensional
representation of the osseous elements of the maxillofacial skeleton
 It is a form of computed tomography in which only a focused, cone-shaped beam of x-rays is
projected at the imaged tissues.
 The limited volume significantly reduces the amount of radiation compared with traditional
computed tomography.
 The resolution of the CBCT image is low, which allows visualization
of very small objects, such as difficult to find canals.

40. Cont…
 Its important in diagnosis and treatment planning for teeth with a complex anatomy or extensive
resorptive lesions.
 Useful in assessing the diagnosis or treatment outcome if the patient
has symptoms but no apparent etiology can be determined.
 The sensitivity of CBCT is higher than that of periapical radiography in detecting periapical
lesions and identifying vertical root fractures.
 Its spartial resolution is however poor compared to conventional radiographs.

41. Cont…
Large internal resorptive lesion and possible
perforation. A and B, Conventional
radiographs with two angles did
not provide enough information on the
extent of the lesion. CBCT
imaging in the coronal (C), sagittal (D), and
axial (E) planes
provides important additional information for
treatment planning

42. Digital Imaging System
The "radio" component consists of a high-
resolution sensor with an active area that is
similar in size to conventional film.
"visio" portion, consists of a video monitor and
display-processing unit . the image is digitized
and stored by the computer.
The unit magnifies the image, can produce
colored images and display multiple images
simultaneously.
further manipulation of the image is possible;
i.e; enhancement, contrast stretching, and
reversing.
A zoom feature is also available to enlarge a
portion of the image.
is the "graphy," a high-resolution video printer
that provides a hard copy of the screen image,
using the same video signal. In addition, a
digital intraoral camera can be integrated with
most systems.

43. Other new technology
 Ultrasonography
 Magnetic resonance Imaging (MRI),
 Radioisotope imaging
 Scanography
 Stereography
 Xeroradiography
 Digital imaging systems
 Computed tomography (CT)
 Direct Subtraction radiography.

44. References
1. Ingles Endodontics 6th Edition- John I Ingle.
2. Essentials of Dental Radiography and Radiology 3rd edition- Erick Whaites.
3. Principle and Practice of Endodontics 5th edition- Maumoud Torabinejad
4. Grossmans Endodontic Practice 13th edition- B. Shuresh Chandra