CAD/CAM manufactured allogeneic bone blocks for three-dimensional ridge augmentation in implant dentistry: a retrospective clinical and radiological analysis.

The edentulous alveolar ridge is a challenge for implant treatment, commonly requiring extensive reconstruction to create an adequate implant site. The aim of this study was to analyse the efficacy of customized cancellous allogeneic bone blocks (CABB) for alveolar ridge augmentation and examine staged implantation in the reconstructed bone. Three-dimensional radiographic images were analysed retrospectively to determine linear bone and volume gain at T1 (postoperative after CABB insertion) and resorption at T2 (after the CABB healing phase). A total 111 implants placed in 66 CABB were investigated retrospectively, and clinical follow-up was performed. At T1, the CABB showed a mean linear bone gain of 6.29 mm horizontally and 6.80 mm vertically, and volume gain of 457 ± 302 mm³. Although complications occurred during the healing phase, there was no total bone block loss. At T2, mean bone dimensions were 4.96 mm horizontally and 5.55 mm vertically, and the volume was 326 ± 250 mm³_, giving a mean volumetric stability of 71.41% ± 18.00%. Five early implant losses occurred, indicating an implant survival rate of 95.5%. The results suggest that CABB can be used successfully to achieve a reasonable increase in bone dimensions for augmentation of three-dimensional alveolar ridge defects, with a high implant survival rate. However, this procedure is technique-sensitive and strict follow-up is required to allow possible intervention.