Bone Loss Patterns PDF

DSV 341 BONE LOSS AND PATTERNS OF BONE DESTRUCTION PRESENTED BY: DR KHALID GUFRAN  Alveolar bone is that part of jaw bone that surrounds and supports the teeth. It has facial and lingual cortical plate or compact bone between which cancellous bone is present.  The margins of...

DSV 341 BONE LOSS AND PATTERNS OF BONE DESTRUCTION PRESENTED BY: DR KHALID GUFRAN  Alveolar bone is that part of jaw bone that surrounds and supports the teeth. It has facial and lingual cortical plate or compact bone between which cancellous bone is present.  The margins of the alveolar crest run parallel to the CEJ at a remarkably constant distance of 1 to 2mm.  DSV 341  Scalloped with knife edge  Factors determining alveolar housing: ◦ Tooth form ◦ Embrassure width ◦ CEJ ◦ Position of the tooth in the arch  DSV 341  Osseous defects are those defects , which are formed as a result of destruction of alveolar bone due to periodontal disease.  The noraml height of alveolar bone is at CEJ and this height is maintained by physiologic equilibrium between bone formation by osteoblasts and bone loss by osteoclasts, which inturn is regulated by local and systemic influences.  Osteoblasts are the primiary cells responsible for the synthesis of the bone matrix, which subsequently undergoes calcification..  Bone destruction in periodontal disease is caused by local factors and systemic factors  DSV 341 1) Chronic gingival inflammation 2) Trauma from occlusion 3) Combination of both  It is the most common cause for bone destruction in periodontal disease.  The transition from gingivitis to periodontitis is associated with changes in the composition of bacterial plaque or resistance of the host.  The lesion present with most pathogenic bacteria, inflammatory cell infiltrate, the lesion becoming more destructive and progressive with the conversion of T- Lymphocyte to B-Lymphocytic lesion. Interproximally Facially and Lingually  Gingival inflammation Marrow spaces Replaced by leukocytes and fluid exudates, new blood vessels and proliferating fibroblasts Increase in osteoclasts and mononuclear cells Thinning of bone trabeculae and enlargement of marrow spaces Destruction of bone and reduction of bone height  Another cause for bone destruction in periodontal disease is trauma from occlusion, which can occur in the absence or presence of inflammation.  Immune deficiencies  Osteoporosis  Smoking  Periodontal bone loss may also occur in generalized skeletal disturbances (e.g hyperparathyroidism, leukemia, or histocytosis X )  Some of the authors suggested that locally produced bone resorption factors may have to be present in the proximity of the bone surface to be able to exert their action.  On the basis of waerhaugs measurements, it was postulated that there is range of effectiveness of about 1.5 to 2.5mm within which bacterial plaque can induce bone loss, beyond 2.5mm there is no effect. 1. Horizontal bone loss 2. Vertical or angular defects 3. Osseous craters 4. Bulbous bony contours 5. Reversed architecture 6. Ledges 7. Furcation involvement  HORIZONTAL BONE LOSS  It is the most common pattern of bone loss in periodontal disease.  The bone is reduced in height but the margins remain roughly perpendicular to the tooth surface.  Associated with suprabony pockets.  Vertical defects occur in oblique direction, leaving a hollowed trough in the bone along the root.  Angular defects are accompanied by infrabony pockets.  Angular defects were classified by goldman and cohen on the basis of the number of osseous walls. 1) One wall or hemiseptal defect- one wall is present 2) Two wall defect- two walls are present 3) Three wall defect- three walls are present ( more common on mesial surfaces of upper and lower molars)  Osseous craters are the concavities in the crest of the interdental bone confined within the facial and lingual walls.  Craters have been found to make up about one third (35.2%) of all defects and about two third (62%) of all mandibular defects. Osseous Craters  Reversed architecture defects are produced by loss of interdental bone, including the facial plates and lingual plates, without concomitant loss of radicular bone, thereby reversing the normal architecture.  Such defects are more common in the maxilla.  BULBOUS BONY CONTOURS  They are bony enlargements caused by exostoses, adaptation to function or buttressing bone formation.  Common in maxilla than mandible  LEDGES :  They are plateau like bone margins caused by resorption of thickened bony plates.  FURCATION INVOLVEMENT: It refers to the invasion of bifurcation and trifurcation of multirooted teeth by periodontal disease.  The mandibular molars are most common sites and least common are maxillary premolars.  Depending on the relative position of the interdental bone to radicular bone, osseous surgery is of following types  POSITIVE ARCHITECTURE  NEGATIVE ARCHITECTURE  FLAT ARCHITECTURE  POSITIVE ARCHITECTURE: The architecture is “positive” if the radicular bone is apical to the interdental bone. FLAT ARCHITECTURE: Flat architecture is the reduction of the interdental bone to the same height as the radicular bone. NEGATIVE ARCHITECTURE: The bone has “negative” architecture if the Interdental bone is more apical than the radicular bone.  1) Clinical examination – Transgingival probing.  2) Radiographs – not very reliable cannot reveal the presence or absence of bony walls.  3) Surgical exposure – during the flap operations, it is the only reliable method for determining the true architecture of bony defects.  Bone loss patterns associated with periodontal disease are varied, and the type of loss can be different in various areas in the same patient.  Vertical bone loss is amenable to regenerative periodontal surgery using a variety of bone graft materials, bioactive molecules,and membranes  Horizontal bone loss and bone craters generally cannot be treated with regeneration, thus these lesions require flap surgery combined with osseous surgery.  Newman & Carranza`s Clinical Periodontology. Michael G. Newman, Henry Takei, Fermin A. Carranza and Perry R. Klokkevold. 13th Edition, 2018. Saunders. ISBN: 9780323523004.  Glossary of Periodontal Terms.