A novel buccal bone augmentation technique around non-contained and exposed implant threads: Clinical, histologic and histomorphometric evaluations on the treatment outcome.

Background/purpose: Buccal dehiscence defects around dental implants pose a significant clinical challenge, particularly when minimal residual bone remains. This prospective study aimed to evaluate a novel two-layer bovine-derived grafting approach-a moldable paste-type material layered with particulate bone-protected by a collagen membrane to encourage new bone formation on exposed implant threads. Materials and methods: Three partially or fully edentulous patients requiring implant-supported rehabilitation were enrolled. A total of 17 implants were placed; among these, three "study implants" exhibited pronounced buccal bone dehiscences and were grafted with the investigated protocol. Six months postoperatively, the designated study implants were retrieved en bloc and processed for histologic and histomorphometric analyses. Bone-to-implant contact (BIC) was measured on both buccal and lingual aspects to assess new bone formation on previously exposed implant threads. Results: All implant sites healed uneventfully, without complications such as wound dehiscence or infection. Histology showed newly formed mineralized tissue in direct contact with the implant surface, supported by a mean total BIC of 67.32 ± 6.27 %. The mean buccal BIC was 66.56 ± 5.52 %, suggesting that some degree of new bone formation occurred in the areas of original thread exposure, although residual graft particles were frequently noted. Conclusion: Within the limits of this preliminary study, the findings suggest that the combined bovine-derived paste and particulate graft technique may help regenerate buccal bone and facilitate osseointegration on exposed implant threads. Further investigations with larger patient samples and extended observation periods are needed to corroborate and refine these encouraging early results.