Long-Term Follow-Up on Soft and Hard Tissue Levels Following Guided Bone Regeneration Treatment in Combination with a Xenogeneic Filling Material: A 5-Year Prospective Clinical Study

Purpose: In the present prospective study, bone augmentation by guided bone regeneration (GBR) in combination with bovine hydroxyapatite (BHA) as filling material was evaluated with regard to soft and hard tissue stability over time. Materials and Methods: Implant survival, radiologic bone level (marginal bone level [MBL]), and clinical soft tissue parameters (marginal soft tissue level [MSTL]) were observed. Twenty patients received a total of 41 implants (Branemark System, Nobel Biocare, Goteborg, Sweden) in conjunction with GBR treatment. The end point of the study was after 5 years following implant placement. Results: The cumulative implant survival rate was 97.5% corresponding to one implant failure. The radiologic evaluation of the MBL demonstrated a crestal bone height above the level of the fixture head. The bone height decreased from -3.51 to -2.38 mm (p < .001). The MSTL was -1.52 mm at baseline and -1.15 mm at the 5-year follow-up (p < .04) demonstrating a stable submucosal crown margin throughout the study period. Conclusion: GBR treatment in combination with a xenogeneic filling material (BHA) is a viable treatment option in order to maintain stable hard and soft tissue levels in conjunction with augmentative procedure related to oral implant treatment.