Simultaneous lateral bone augmentation and implant placement using a particulated synthetic bone substitute around chronic peri-implant dehiscence defects in dogs

Aim: To determine the histological outcomes when using a highly porous synthetic bone substitute and a cross-linked collagen membrane for lateral bone augmentation of peri-implant dehiscence defects. Methods: In eight dogs, three treatment groups were randomly allocated at each peri-implant dehiscence defect (mean height × depth = 3 × 1 mm) as follows: (i) synthetic bone substitute covered by a cross-linked collagen membrane (test group), (ii) deproteinized bovine bone mineral covered by a natural collagen membrane (positive control), and (iii) no treatment (negative control). Two healing periods (8 and 16 weeks) were applied. Results: The differences in healing outcomes between the test and positive control groups were not significant at 8 weeks. Horizontal bone augmentation 2 mm below the implant shoulder was significantly greater in the test group (1.22 ± 0.53 mm) than in the positive and negative controls (0.42 ± 0.51 and 0.36 ± 0.50 mm, respectively) at 16 weeks. Similarly, the augmented tissue thickness at 0, 1, and 2 mm apical to the implant shoulder was significantly greater in the test group than in the positive control group. Conclusion: The test group showed significantly better histological outcomes for lateral bone augmentation and tissue thickness at 16 weeks compared to both the positive and negative control groups.