(73) A Decision-Making Process for Selection of Allogenic and Xenogenic Combination Bone Substitute for Alveolar Ridge Preservation

Introduction: Alveolar ridge preservation (ARP) is a widely common procedure performed after extractions to prepare the site for future implant placement. Several factors have been reported to influence the selection of appropriate bone graft material and barrier membrane. The aim of this case series is to present a decision-making process in presenting the clinical situations when a combination of allogeneic and xenogenic materials are used for ARP.

Methods: Various studies have described the influence of risk factors in bone regeneration. This includes systemic factors (diabetes, radiation, chemotherapy, anti-resorptive medications, social habits); local factors (failed sites, active infection, congenitally missing teeth, traumatic injuries); and technical factors (soft tissue quality, infection, wound dehiscence, iatrogenic complications, lack of graft stability and graft vascularity). The above-mentioned risk factors in addition to the condition of the alveolar ridge (intact wall, fenestration or dehiscence, missing walls) can influence the selection of an appropriate bone graft material, barrier membrane and the use of biologic materials.

Results: A decision tree was created which integrated systemic, local, technical risk factors and condition of the alveolar ridge walls after extraction for appropriate bone graft, barrier membrane and biologic material selection. The decision tree was used to treat a series of ARP. Case #1 (Image 1) involved extraction of a non-restorable tooth #12. Patient had no significant medical history, and no risk factors were present. Alveolar ridge was intact upon atraumatic extraction. A mix of allograft and xenograft granules was used along with a resorbable collagen matrix as an orifice barrier. Case #2 (Image 2) involved a patient with a history of infection and abscess related with tooth #30. Antibiotics were prescribed prior to extraction to control infection. Upon extraction, a buccal dehiscence was present. A combination of xenograft and allograft granules, and a resorbable cross-linked membrane was used for ARP. Case #3 (Image 3) involved a fractured tooth #9 with a draining fistula. The tooth had internal root resorption and the patient was prescribed antibiotics prior to extraction. Upon extraction, the buccal wall was missing. A resorbable cross-linked membrane was inserted into the socket with a mix of allograft and xenograft granules and rhPDGF-BB growth factor.

Conclusions: It is highly important to consider various risk factors along with condition of the alveolar ridge for appropriate selection of material for ridge preservation for best long-term outcome. A combination of xenogenic and allogenic bone grafting material could be considered a successful treatment modality for alveolar ridge preservation cases involving different socket wall conditions.

Lead Author's Contributions to the Research Project. : The Lead Author was responsible for performing data collection, and composition of the abstract.