Histological evaluation of edentulous alveolar ridge horizontal bone augmentations using a xenogeneic bone substitute and autologous platelet concentrates: A prospective case series

Purpose: This case series aimed to assess the efficacy of a novel horizontal ridge augmentation modality using histomorphometry. Combinations of “sticky bone” and tenting screws without autologous bone were used as augmentative materials. Methods : Five individuals presenting healed, atrophic, partially edentulous sites that required horizontal bone augmentation before implant placement were enrolled. Patients underwent the same augmentation type and five months of postoperative reentry procedures. The first surgery served as implant site development, while the biopsy and corresponding implant placement were performed during reentry. The bone was qualitatively analyzed using histology and histomorphometry and quantitatively evaluated using cone-beam computed tomography (CBCT). Results : Four individuals healed uneventfully. Early wound dehiscence occurred in one case. Histology showed favorable bone substitute incorporation into the newly formed bone and intimate contact between de novo bone and graft material in most cases. Histomorphometry reveled an average of 48% newly formed bone, 19% graft material, and 33% soft tissue components. The CBCT-based mean alveolar ridge horizontal increase was 3.9 mm at five months postoperatively. Conclusions: The described augmentation method appears suitable for implant site development resulting in favorable bone quality according to histology. The presence of 48% de novo bone and 33% connective tissue formation on average is highly preferable. However, clinicians must accommodate 1–2 mm resorption in augmentative material width at the buccal aspect, which might indicate a secondary lateral augmentation during implant placement. Trial registration: ClinicalTrials.gov, ID: NCT05612737. Registered 30 October 2022- Retrospectively registered, https://register.clinicaltrials.gov/prs/app/template/EditRecord.vm?epmode=Edit&listmode=Edit&uid=U0005NHB&ts=6&sid=S000CMHA&cx=-bgh60i