Periodontal bone defects
In terms of clinical attachment level gain and probing pocket depth (PPD) reduction, a surgical approach (open flap debridement) has been proven beneficial for the treatment of deep periodontal intrabony pockets (PPD ≥ 6 mm). Guided Tissue Regeneration (GTR) and enamel matrix derivative have been considered the gold standard in regenerative periodontal therapy.
GUIDED TISSUE REGENERATION (GTR)
Periodontal intrabony defects can be predictably treated with a barrier membrane in the sense of GTR. Following flap elevation and granulation tissue removal, a membrane is placed between the gingiva and cleaned root surface to cover the defect area completely. Finally, the flap is repositioned and sutured tension-free. Hereby, cells originating from the intact periodontal ligament is given time and space to repopulate the root surface resulting in regeneration of the lost periodontal structures, i.e. root cementum, periodontal ligament and alveolar bone.
ENAMEL MATRIX DERIVATIVE
Enamel matrix derivative (EMD, Straumann® Emdogain®) has been shown to be effective in sites of >6 mm PPD associated with a radiographic vertical bone loss >3 mm. Human histological data have demonstrated that EMD induces the de novo formation of root cementum, periodontal ligament and alveolar bone.
CONTAINED AND NON-CONTAINED DEFECTS
The defect morphology is crucial for the success of the treatment. Self-contained intrabony defects are narrowed by predominantly intact osseous walls (i.e. 3-wall defects) and are indicated for a regenerative therapy with either a barrier membrane or EMD alone.
Non-contained intrabony defects (1- or 2-wall defects) usually require support of the soft tissue, thus different kind of bone grafts may be associated with the use of a barrier membrane or EMD respectively.