Guided Bone Regeneration Using Carbonated Apatite Granules and L-Lactic Acid/ε-Caprolactone Membranes: A Case Series and Histological Evaluation.

Background/Objectives: The newly developed poly L-lactic acid/ε-caprolactone (P(LA/LC)) membrane has recently been proposed as a guided bone regeneration (GBR) procedure in implant treatment. This case series details the clinical, radiographic, and histological results of ridge augmentation using bone graft comprising a P(LA/LC) membrane and carbonated apatite for implant treatment. Methods: Ten patients (15 sites) requiring bone augmentation and implant placement were retrospectively assessed. Simultaneous implant placement (Si) was performed at five sites in three patients. Si immediately following tooth extraction (SiIP) was performed at four sites in four patients. The staged approach (St) was performed at six sites in three patients. In the St-treated cases, hard tissue samples were taken from the implant placement site under patient consent. Results: The mean regenerated bone width for each treatment method was Si, 6.34 ± 2.64 mm (excluding implant diameter, 2.60 ± 2.42); SiIP, 7.55 ± 1.17 mm (excluding implant diameter, 3.90 ± 0.78) and St, 5.57 ± 1.08 mm. The mean regenerated bone width for all the cases was 6.36 ± 1.83 mm (excluding implant diameter, 4.14 ± 1.99). Significant differences were observed between the pre- and post-operative bone width in all the cases and the SiIP group (p < 0.001). All cases were followed up for more than 2 years after attaching the superstructure. No inflammation, shrinkage, or other problems were observed in the hard and soft tissues surrounding the implant. In the histological evaluation, there was no soft tissue ingrowth into the augmented bone, and new bone formation was observed. Conclusions: The use of P(LA/LC) membranes and carbonated apatite as GBR materials in implant treatment resulted in stable and favorable bone augmentation.