bone loss patterns

bone loss patterns

1. BONE LOSS & PATTERNS OF BONE DESTRUCTION

2. CONTENTS INTRODUCTION CAUSES OF BONE DESTRUCTION IN PERIODONTAL DISEASE Extension of gingival inflammation Trauma from occlusion Systemic disorders FACTORS DETERMINING BONE DESTRUCTION IN PERIODONTAL DISEASE BONE DESTRUCTION PATTERNS IN PERIODONTAL DISEASE LESIONS CAUSING ALVEOLAR BONE DESTRUCTION CONCLUSION REFERENCES

3. Introduction Periodontitis Bone loss  past pathologic experience

4.  Blood calcium Receptors on chief cells of PTH Release of PTH IL-1, IL-6 LIF Release calcium Osteogenic substrates BONE COUPLING Osteoblasts Monocytes Osteoclasts Bone Introduction RANKL , M-CSF

5. Introduction Mechanisms of bone destruction Osteolysis ( Halisteresis ) (Von Recklinghausen F 1910) Non-cellular resorption Vascular resorption (Jaffe HL 1930) Osteoclasis ( Lacunar resorption) ( McClean FC, Urist MR 1961)

6. Introduction Mediators of bone destruction STIMULATORS INHIBITORS IL-1 IFN-γ IL-6 OPG TNF Estrogens PTH , PTHrP Androgens PGE 2 Calcitonin M-CSF PDGF , bFGF RANK / RANKL IGF Endotoxins TGF  Enzymes Drugs affecting bone metabolism Calcitonin, vit D Calcineurin inhibitors Bisphosphonates HRT drugs SERM NSAIDs Tetracyclines Glucocorticoids

7. Causes of bone destruction Gottlieb & Orban 1938  “senile atrophy” Male patient aged 67 years old. O/E: generalized class 1 gingival recession with generalized interdental bone loss. No periodontal pockets probed or tooth mobility observed.

8. Causes of bone destruction

9. BONE DESTRUCTION CAUSED BY EXTENSION OF GINGIVAL INFLAMMATION Gingivitis Periodontitis Bacterial composition ( Lindhe J et al 1980 ) Cellular composition ( Seymour & associates 1978, 1979 ) Immunologic activity ( Ruben M 1981 )

10. Bone destruction caused by extension of gingival inflammation Spread of inflammation Gingiva Blood vessels, collagen fibres Alveolar bone Marrow spaces

11. Bone destruction caused by extension of gingival inflammation Bone destruction = Bone necrosis ( Kronfeld R 1935 ) Amount of infiltrate correlates with the degree of bone loss Distance from the apical border of the infiltrate correlates with number of osteoclasts ( Rowe DJ 1981, Lindhe J 1978 )

12. Bone destruction caused by extension of gingival inflammation Pathways of spread of inflammation A B A – Interproximally B – Facially& lingually

13. Bone destruction caused by extension of gingival inflammation Pathways of spread of inflammation

14. Bone destruction caused by extension of gingival inflammation Radius of action Garant and Cho 1979 Page and Schroeder 1982 (based on Waerhaug’s experiments 1980 ) Tal H 1984 – human patients 1.5 – 2.5 mm

15. Bone destruction caused by extension of gingival inflammation Rate of bone loss ( Loe & associates 1986 ) ~ 0.2 mm a year for facial surfaces ~ 0.3 mm a year for proximal surfaces Rapid progression of periodontal disease (~ 8%) CAL = 0.1 to 1mm yearly Moderately progressive disease (~ 81%) CAL = 0.05 to 0.5mm yearly Minimal progression of periodontal disease (~ 11%) CAL = 0.05 to 0.09mm yearly

16. Bone destruction caused by extension of gingival inflammation Periods of bone destruction Page and Schroeder 1982 – inflammation Seymour GJ 1979 – B-lymphocytes Newman MG 1979 – microflora Saglie RF 1987 – bacterial invasion + host defense Periods of inactivity Periods of activity

17. Potential pathways for interaction between factors in plaque and alveolar bone resulting in alveolar bone loss Gingival tissue Release or activation of soluble mediators Bacterial plaque Soluble factor(s) Alveolar bone Bone progenitor cell Osteoclast 3 1 2 4 5 Bone destruction caused by extension of gingival inflammation Hausmann E 1974

18. Bone destruction caused by extension of gingival inflammation Bone formation in periodontal disease Retards the rate of bone loss Newly formed osteoid more resistant to resorption than mature bone ( Irving JT 1969 ) Buttressing bone formation Affects the outcome of treatment

19. BONE DESTRUCTION CAUSED BY TRAUMA FROM OCCLUSION In the absence of inflammation When combined with inflammation Glickman’s concept (1965, 1967) Waerhaug’s concept (1979)

20. BONE DESTRUCTION CAUSED BY SYSTEMIC DISORDERS Bone factor concept ( Glickman I 1951 ) The systemic regulatory influence upon the response of alveolar bone is termed the “bone factor” in periodontal disease. Systemic factors Local factors

21. Bone destruction caused by systemic disorders Role of “bone factor” in determining diagnosis and prognosis Positive bone factor Negative bone factor Patient’s age Gingival inflammation & occlusal disharmony Bone loss

22. Bone destruction caused by systemic disorders Clinical implications Positive bone factor in a 42-year old female with gingival inflammation and poor oral hygiene but minimal bone loss. Negative bone factor in a 41-year old female with gingival inflammation and poor oral hygiene but severe bone loss.

23. BONE FACTOR GERIATRIC NUTRITIONAL HEREDITARY DEBILITATING CONSTITUTIONAL PSYCHOSOMATIC STRESS DYSTROPHIC HORMONAL Functional Microbial Thermal Mechanical Chemical

24. Factors determining bone destruction in periodontal disease Normal variation in alveolar bone

25. Interdental septa Alveolar plates Root & root trunk anatomy Root position Teeth alignment Root proximity Factors determining bone destruction in periodontal disease

26. Factors determining bone destruction in periodontal disease 1. interdental septum is wide craters and infrabony defects. narrow interdental septum the margin is destroyed inconsistent margin interproximal crater or hemiseptum . 2. marginal bone is thin; marginal bone is destroyed by inflammation from marginal gingiva. marginal bone is thick, deep trough like intrabony defect may develop. 3. root fenestration or dehiscence buccal side . thick marginal ledge lingual side.

27. Factors determining bone destruction in periodontal disease Exostoses Nery EB 1977 – palatal exostoses (40%) Buttressing bone formation ( Lipping ) Food impaction

28. Bone destruction patterns in periodontal disease Classification Goldman HM, Cohen DW (1958) Prichard JF (1965) Karn KW (1983) Grant DA, Stern IB , Listgarten MA (1988) Papapanou NP, Tonetti MS (2000)

29. Bone destruction patterns in periodontal disease Goldman HM, Cohen DW (1958) Suprabony defect Intrabony defect One-wall Two-wall Three-walls Combined

30. Bone destruction patterns in periodontal disease Prichard JF (1965) Thickened margin Interdental crater Hemiseptum Infrabony defect with three osseous walls Infrabony defect with two osseous walls Infrabony defect with one osseous wall Marginal gutter Furcation involvement Irregular bone margin Dehiscence Fenestration Exostosis

31. Bone destruction patterns in periodontal disease Karn KW (1983) Crater Trench Moat Ramp Plane Cratered ramp Ramp into crater or trench Furcation invasions

32. Bone destruction patterns in periodontal disease Grant DA, Stern IB , Listgarten MA (1988) A. Vestibular, lingual or palatal defects associated with: 1. Normal anatomic structures External oblique ridge Retromolar triangle Mylohyoid ridge Zygomatic process 2. Exostosis and tori Mandibular lingual tori Buccal and posterior palatal exostosis 3. Dehiscences 4. Fenestrations 5. Reverse osseous architecture B. Vertical defects: Three walls Two walls One wall Combination with a different number of walls at the various levels of the defect. C. Furcation defects: Class I or incipient Class II or partial Class III or through and through

33. Bone destruction patterns in periodontal disease Papapanou NP, Tonetti MS (2000)

34. Bone destruction patterns in periodontal disease Nomenclature Horizontal bone loss Vertical / angular bone loss Crater Trench Moat Ramp Plane Bulbous bone contours Reverse architecture Ledges Fenestrations and dehiscences Furcation involvement

35. Bone destruction patterns in periodontal disease Horizontal bone loss Vertical or angular defects

36. Bone destruction patterns in periodontal disease Vertical or angular defects (Nielsen JI 1980) Prevalence rate: 60% of persons Commonly seen involving interproximal surfaces

37. Bone destruction patterns in periodontal disease Three – wall defect Sarati et al (1968), Larato DC (1970) – posterior segment

38. Bone destruction patterns in periodontal disease Two – wall defect Crater-like – most common Non-crater – like

39. Bone destruction patterns in periodontal disease One – wall defect Hemiseptal defect

40. Bone destruction patterns in periodontal disease Combined defect

41. Bone destruction patterns in periodontal disease Osseous craters Interproximal crater with heavy ledges. Pre-op & post-op.

42. Bone destruction patterns in periodontal disease Saari et al (1968) – most common defect Vulnerability of the col ( Cohen 1959 ) Plaque retentive Interdental bony configuration ( Manson 1963 ) Spread of inflammation ( Weinmann 1941, Goldman 1957 ) Cancellous trabeculation is more reactive ( Amprino & Marotti 1964 )

43. Bone destruction patterns in periodontal disease Trench Moat Ramp Plane

44. Bone destruction patterns in periodontal disease Bulbous bone contours Pre-operative buccal view Pre-operative occlusal view Post-operative buccal view

45. Bone destruction patterns in periodontal disease Ledges Blunted interdental septa with bone ledges Small crater with heavy ledges Hemisepta with heavy ledges

46. Bone destruction patterns in periodontal disease Reversed architecture Positive Flat Negative Negative architecture

47. Bone destruction patterns in periodontal disease Fenestrations and dehiscences Dehiscence Fenestrations

48. Bone destruction patterns in periodontal disease Furcation involvement Stage in the progress of tissue destruction Increases with age ( Larato DC 1970, 1975 ) Horizontal / angular bone loss evident Factors contributing to furcation involvement

49. Bone destruction patterns in periodontal disease Classification by Glickman (1953) Grade I Grade II Grade III Grade IV