Radiographic aids in dx of periodontol ds part 1

1. -
Radiographic Aids In Diagnosis of
Periodontal Diseases – Part A

2. CONTENTS
1. Introduction.
2. History.
3. Radiographs.
4. Interpretation of radiological examination.
5. Interpretation in relation to periodontal diseases.
6. Advances in radiographs.
7. Limitations of radiographs.
8. Implant imaging (Briefly).
9. Conclusion.
10. References.
2

3. Introduction3

4. History4

5. HISTORY
• Discovery of X-Rays - November 8th , 1895
Forms of tube used by Roentgen in 1895–1896 for the
production of X rays.
Wilhelm Conrad Roentgen
(1845 – 1923)
5

6. HISTORY
• First Dental Radiograph – 12th January, 1896
Dr. Otto Walkoff
(1860 – 1934)
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7. HISTORY
• First Intraoral Dental Radiograph – Early 1896
Dr. Edmund Kells
(1856 – 1928)
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8. HISTORY
• First Intraoral Dental Radiograph – Early 1896
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9. Radiographs9

10. It is the traditional method to asses the destruction of
alveolar bone associated with periodontitis.
CONVENTIONAL RADIOGRAPH CAN BE USED TO
EVALUATE
 Bone levels
 Bone loss – even or angular patterns
 Intra(infra) – bony defects
 Root morphologies ⁄ topographies
 Furcation radiolucencies
 Endodontic lesions
 Endodontic mishaps
 Developmental anomalies
 Root length and shape(s) remaining in bone
10

11. 11

12. RADIOGRAPHS
INTRA ORAL
IOPA,
BITEWINGS
& OCCLUSAL
EXTRA ORAL
OPGS
12

13. Intra Oral Periapical Radiographs
Paralleling technique
 Also called as “right angle” or “long cone technique”.
 X-ray film is placed parallel to long axis of tooth and central
ray of x-ray beam is directed at right angle to teeth & film.
 Preferable technique for periodontal use.
13

14. Intra Oral Periapical Radiographs
Bisecting angle technique
 Central ray is directed at right angles to a plane bisecting the
angle between long axis of teeth & film.
 Makes the bone margin appear more closer to the crown.
14

15. Extra Oral Periapical Radiographs
Newman And Friedman 2003
Limitations with intraoral periapical radiographic imaging:
 Advancing age
 Anatomical difficulties like large tongue, shallow palate, restricted
mouth opening,
 Neurological difficulties, and size of radiographic sensor
15

16. Extra Oral Periapical Radiographs
Chen et al in 2007
 Developed a sensor beam alignment aiming device for performing
radiographs using this technique
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17. Bitewing Radiographs
Records the coronal part of upper & lower dentition along with
periodontium.
Uses:
 To study height & contour of interdental alveolar bone.
 To detect interproximal calculus.
 To detect periodontal changes
17

18. Bitewing Radiographs
Horizontal bitewing radiographs
 Useful for proximal caries detection.
 Limited use in periodontal treatment
and treatment planning if bone loss is
advanced.
Vertical bitewing radiographs
 Film is placed with its long axis at 90º
to the placement for horizontal
bitewing radiography,
 Can be helpful in evaluating
periodontium.
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19. Occlusal Radiographs
 Intraoral occlusal radiographs enable viewing of a relatively large
segment of dental arch.
 They are useful in patients who are unable to open mouth wide
enough for periapical radiographs
19

20. Extraoral Radiographs
 When large areas of the skull or jaw must be examined or,
 When patients are unable to open their mouths for film placement.
 Useful for evaluating large areas of the skull and jaws but are not
adequate for detection of subtle changes such as the early stages of
dental caries or periodontal disease.
20

21. Orthopantomograph
 Technique for producing single tomographic image of facial
structures including maxillary and mandibular arches with their
supporting structures.
 Based on principle of the reciprocal movement of x-ray source and
image receptor around a central plane known as image layer.
21

22. Orthopantomograph
 Image distortion
 Lingual structures would be projected higher than buccal surfaces
 Less details than intraoral images
 Production of ghost images
Limitations of OPG
It can be used as a alternative
for intra oral full mouth series
when combined with bite wing
radiographs
22

23.  Panoramic radiographs may not reveal alveolar bony defects as
accurately as periapical radiographs.
 But question is whether there is any additional therapeutic yield
from greater accuracy from IOPAs
 The periodontal structures of interest noted on periapical
radiographs are also noted on panoramic radiographs.
 The radiographic features of interest on a panoramic radiograph
supplemented when necessary by a small number of intra-oral
views, is sufficient for the management of periodontal diseases
Tugnait et al. 2000,2005
Pepallasi EA et al. 2000
23

24.  Determined the efficacy of panoramic radiographs
in the preoperative planning of posterior mandibular
implants .
 Mental nerve parasthesia - following implant
placement in 1527 patients with 2584 implants with
only OPGs as preoperative imaging technique.
 No permanent sensory disturbances of the inferior
alveolar nerve.
 Only 2 cases i.e. 0.08 % reported paraesthesia.
 Panoramic examination is a safe preoperative
evaluation tool.
Vazquez et al 2007
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25.  Image can be instantly viewed by patient & dentist.
 Reduction in radiation received by patient by as much 50% to 80%
 Images can be altered to achieve task specific image characteristics
for e.g. density & contrast can be lowered for evaluation of marginal
bone and increased for evaluation of implant components.
 Enables the dental team to conduct remote consultations.
 Computerized images can be stored, manipulated & corrected for
under & overexposure
Digital Radiography
Advantages
25

26. Based on use of Charged Couple Device.
 Radio – X-ray generator connected to sensor.
 Visio – storage of incoming signals during exposure and conversion to
grey levels.
 Graphy – digital mass storage unit connected to various video
printout devices.
Radiovisiography
Duret F et al 1988
26

27. Radiovisiography
Mechanism of Image Display
Radiographic digital detector
Conventional radiographic
source used to expose sensor
Detector converts X-rays to
visible image
Image display on monitor 27

28.  Comparative study for marginal bone between RVG and after
surgical exploration
 Presented that Majority showed difference of less than 0.5 mm
between two techniques
 The RVG system when compared with conventional uses
considerably reduced levels of radiation to produce an image
immediately after exposure.
Mouyen F et al 1989
Adosh L in 1997
28

29.  Evaluated the accuracy of RadioVisioGraphy (RVG) in the linear
measurement of interproximal bone loss in intrabony defects.
 Comparison between RVG measures and intrasurgical estimates were
performed in 56 teeth with intrabony defects.
 The radiographic measurements overestimated interproximal bone loss
as compared to the intrasurgical measurements.
A.R.Talaiepour et al in 2005
29

30.  Depends up on conversion of serial radiographs into digital images.
 The serially obtained digital images are superimposed & image
intensities of corresponding pixels are subtracted
If change has occurred
 The brighter area represents gain
 Darker area represents loss
Digital Subtraction Radiography
Zeidses des Plantes 1935
30

31. Base Line After OneYear Bone Gain
 5% of bone loss can be detected.
 Diagnostic subtraction radiography
(DSR) can be used for enhanced
detection of crestal or periapical bone
density changes and to evaluate caries
progression
Ortmann 1994
31

32.  Baseline projection geometry and image density should be
reproduced
 bite blocks must be made and attached to the film holders and the
film holder must be reproducibly aligned to the x-ray beam
collimating device
Standardization
32

33. Overall contrast is improved
Trabecular marrow spaces are
visualized
Enhancement of low and high
density images
No objective description.
High standardization of x rays.
No reduction in exposure .
ADVANTAGES DISADVANTAGES
33

34. Extra Oral Digital Imaging
34

35.  Designed to image a slice or plane of tissue
 Accomplished by blurring the images lying outside the plane of
interest
 It consists of an x ray tube and radiographic film rigidly connected
which moves about a fixed axis and fulcrum
 As exposure begins, the tube and film move circumferentially
simultaneously .
 Objects located with in the fulcrum remain in fixed positions and
are viewed clearly.
ConventionalTomography
Godfrey Hounsfield and Allan MacLeod
Cormack 1979
35

36. 36

37.  Computer algorithms use photon counts to construct digital CS
images
 Images are displayed in individual blocks ----- VOXELS
 Each square of the image is matrix ---- PIXELS
 Each pixel is assigned a CT number representing tissue density
 CT number HOUNSFIELD units
Range -1000 to 1000
ConventionalTomography
CT Image Construction
37

38.  Eliminates superimposition of images of structures outside area of
interest
 High contrast resolution – differences between tissues that differ in
density < 1% - can be distinguished
 Images can be viewed in axial coronal and sagittal planes
ConventionalTomography
Advantages
38

39.  Used Computed tomography (CT) in studies in relation to periodontal
defects.
 CT does not offer any favourable cost benefit, dose exposure or
therapeutic yield advantage in periodontal practice and is unlikely to find
a routine.
NaitoT et al. 1998;
Pistorius A et al. 2001
39

40.  Utilizes cone shaped source of ionizing radiation & 2D area detector
fixed on a rotating gantry.
 Multiple sequential images are produced in one scan.
 Rotates 360° around the head.
 Scan time typically < 1 minute.
Cone Beam ComputedTomogrphy
40

41. INTERFACE CONE-BEAMCT MANAGEMENT SOFTWARE
Cone Beam ComputedTomogrphy
41

42.  Evaluation of the jaw bones.
 Implant placement and evaluation.
 EvaluationTMJ.
 Bony & Soft tissue lesions.
 Periodontal assessment.
 Endodontic assessment.
 Alveolar ridge resorption.
 Orthodontic evaluation.
 3D reconstructions.
Cone Beam ComputedTomogrphy
Indications
42

43. PANORAMIC CBCT
Undistorted
CS, Axial, Coronal Sagittal
views
Separated structures
Distorted images
Only one layer view
Superimposition
43

44. CTV/S CBCT
 ConventionalCT scanners make
use of a fan-beam and Provides a
set of consecutive slices of image.
 ConventionalCT makes use of a
lie-down machine with a large
gantry.
 Greater contrast & resolution.
 More discrimination between
different tissue types (i.e. bone,
teeth, and soft tissue)
 Utilize a cone beam, which
radiates from the x-ray source in a
cone shape, encompassing a large
volume with a single rotation.
 A sitting-up machine of smaller
dimensions
 Commonly used for hard tissue.
 Ease of operation.
 Dedicated to dental.
 Lower radiation burden.
44

45. CT V/S CBCT
 Artefacts arising from metal
restorations are more severe using
conventionalCT.
 Artefacts that arise from metallic
restorations are less severe.
45

46.  Compared radiographs with CBCT
 Results: Three-dimensional capability of CBCT offers a significant
advantage in linear measurements for periodontal defect
 All defects can be detected and quantified.
Kelly A. Misch et al . 2006
Mol A and Balasundaram 2008
 EvaluatedThe NewTom 9000CBCT scanner
 Results: Better diagnostic and quantitative information on
periodontal bone levels in three dimensions than conventional
radiography can be obtained
46

47.  Compared the measurements from digital IR and CBCT images to
direct surgical measurements for the evaluation of regenerative
treatment outcomes.
 Compared to direct surgical measurements, CBVT significantly
more precise and accurate than IRs.
 CBVT may obviate surgical re-entry as a technique for assessing
regenerative therapy outcomes
Brently A. et al 2009
Walter C et al. 2011
 Suggests that cone-beam CT may
provide detailed information about
furcation involvements in patients with
chronic periodontitis and so may
influence treatment planning decisions 47

48. Interpretation of Radiographs48

49.  Detailed understanding of three dimensional anatomy and how
structures appear radiologically.
 Know the differences in radiologic anatomy in a 2D & a 3D
radiograph.
 Must possess knowledge of diseases which are potentially
assosciated with all structures in the FOV.
 Must be aware and knowledgable of all different imaging modalities.
 Optimal viewing conditions are essential.
Interpretation of Radiographs
Basic Prerequisites
49

50.  Recognizing the presence of an abnormality.
 Radiologic evaluation of a lesion –
o Location.
o Shape and Contour.
o Border.
o Internal appearances.
 Adjacent anatomic structures
 Interpretation of the findings.
Interpretation of Radiographs
Key Steps in Interpretation
50

51. References
1. Clinical PeriodontologyAnd Implant Dentistry; Jan Lindhe; 6th Edn
2. Oral Radiology-principles And Interpretation; Stuart C. White; 5th
Edn
3. Clinical Periodontology; Newman, Takei, Klokkevold, Carranza; 10th
Edn
4. Radiology In Periodontics – A Review ; J. IndianAcademy Of Oral
Medicine & Radiology; 2013; 25 (1); 24-29.
5. P.F.Van Der Stelt; Modern Radiographic Methods InThe Diagnosis
Of Periodontal Disease;Adv Dent Res 7(2):158-162,August, 1993
6. Bragger U: Digital Imaging In Periodontal Radiography-A Review; J
Clin Periodontol 1988: 15: 551-557
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52. PART B
1. Interpretation in relation to periodontal diseases.
2. Advances in radiographs.
3. Limitations of radiographs.
4. Implant imaging (Briefly).
5. Conclusion.
6. References.
52

53. Next Presentation – OnThursday
19/05/2016
Journal Club Presentation By–
1. Dr. Leena Parmar
2. Dr. Reshma Avadh
THANK
53