Single-staged vs. two-staged implant placement using bone ring technique in vertically deficient alveolar ridges - Part 1: histomorphometric and micro-CT analysis

Background Simultaneous implant placement with bone grafting shortens the overall treatment period, but might lead to the peri‐implant bone loss or even implant failure. The aim of this study was to compare the single‐staged to two‐staged implant placement using the bone ring technique. Material and methods Four standardized alveolar bone defects were made in the mandibles of nine dogs. Dental implants (Straumann BL®, Basel, Switzerland) were inserted simultaneously with bone ring technique in test group and after 6 months of healing period in control group. Animals of both groups were euthanized at 3 and 6 months of osseointegration period. The harvested samples were analyzed by means of histology and micro‐CT. Results The amount of residual bone decreased while the amount of new bone increased up to 9 months of healing period. All morphometric parameters remained stable between 3 and 6 months of osseointegration period within groups. Per a given time point, median area of residual bone graft was higher in test group and area of new bone in control group. The volume of bone ring was greater in test than in control group, reaching the significance at 6 months of osseointegration period (P = 0.002). Conclusions In the present type of bone defect, single‐staged implant placement may be potentially useful to shorten an overall treatment period.