Augmentation stability and early wound healing outcomes of guided bone regeneration in peri-implant dehiscence defects with L- and I-shaped soft block bone substitutes: A clinical and radiographic study.

OBJECTIVES: To retrospectively evaluate whether guided bone regeneration (GBR) with L- and I-shaped demineralized bovine bone mineral with 10% collagen (DBBM-C) differs from GBR with DBBM in terms of augmentation stability and early wound healing outcomes in peri-implant dehiscence defects. METHODS: A total of 91 peri-implant defects were grafted with 24 L- (GBR-L), 22 I (GBR-I)-shaped DBBM-C, and 45 DBBM (GBR-P). Cone-beam computed tomography images were obtained after surgery and at 5 months follow-up. The horizontal thickness (HT0, HT2, HT4), vertical thickness (VT), and VT at 45 degrees angle (45-VT) of the augmented hard tissue were measured. Early postoperative discomfort and wound healing outcomes were assessed 2 weeks after surgery, and periotest values were also measured at 5 months in all groups. RESULTS: At 5 months follow-up, the change at HT0 and VT of the GBR-L (HT0: -0.63 +/- 0.55 mm, VT: -0.77 +/- 0.60 mm) and GBR-I (HT0: -0.68 +/- 0.53 mm, VT: -0.91 +/- 0.73 mm) groups was significantly more stable than that of the GBR-P (HT0: -1.30 +/- 0.77 mm, VT: -1.57 +/- 0.67 mm) group (p < .05). The GBR-L group (-0.74 +/- 0.54 mm) showed better augmentation stability than the other two groups at the change at 45-VT. Early postoperative discomfort, wound healing outcomes, and periotest values did not differ significantly between the three groups. CONCLUSION: Within the limitations of this study, L- and I-shaped DBBM-Cs used for GBR were more beneficial in terms of horizontal augmentation stability than DBBM after a 5-month healing period.