Dimensional alterations following vertical ridge augmentation using collagen membrane and three types of bone grafting materials: A retrospective observational study

Background: Various biomaterials have been introduced for vertical ridge augmentation to replace autogenous block bone grafting. Purpose: This retrospective study radiographically evaluated dimensional alterations of the vertically augmented alveolar ridge using collagen membrane and 3 types of materials: autogenous bone block, allogenous bone block, and particulated bone substitute. Materials and methods: The electronic medical records of 32 patients who received vertical ridge augmentation using 3 types of materials were searched: 9 for autogenous bone block, 12 for allogenous bone block, and 11 for particulated bone substitutes. The vertical bone gain, progression of bone resorption, and peri-implant marginal bone loss after prosthetic loading were measured on follow-up radiographs. Results: The alveolar ridge was vertically augmented by 5.13 ± 1.61, 4.54 ± 2.48, and 3.90 ± 0.85 mm (mean ± standard deviation) after grafting with autogenous bone block, allogenous bone block, and particulated bone substitute, respectively. The radiographic vertical height of the augmented ridge that received autogenous bone block reduced continuously during the first year but was stable thereafter. Sites that received allogenous bone block or particulated bone substitute exhibited dimensional shrinkage for up to 1.5 years postsurgery. However, the peri-implant marginal bone loss did not exceed 1 mm throughout the observational periods in all groups. Conclusions: The clinical findings of this study suggest that the alveolar ridge can be vertically augmented using either allogenous bone block or particulated bone substitute. However, they require a longer healing period to ensure dimensional stability compared to the autogenous bone block.