Tissue changes around dental implants installed in alveolar ridge preservation sites: A 1‐year follow‐up randomized controlled clinical trial

Abstract Objective This study aimed to assess radiographic marginal bone changes 22 months post extraction, which is 1 year after implant loading in alveolar ridge preservation (ARP) sites grafted with a combination of collagen‐embedded xenogenic bone substitute (DBBM‐C) and collagen matrix (CMX), comparing them with implants placed in naturally healed sites. Methods This randomized controlled clinical trial was conducted over 22 months. Patients who needed a single tooth extraction and subsequent implant placement in nonmolar areas were enrolled. The test group received deproteinized bovine bone mineral with 10% collagen covered by a procaine collagen membrane, while the control group allowed spontaneous healing. Radiographic bone level changes were documented using periapical radiographs at implant placement and follow‐up visits (6, 10, and 22 months postextraction). Early implant soft tissue exposure, clinical parameters, and patient‐reported outcomes were recorded. Results Twenty‐two out of 28 participants completed a 22‐month follow‐up, 9 in the test group and 13 in the control group. At 10‐month postextraction follow‐up, the mean MBL was 1.01 ± 1.04 mm in the treatment group and 0.81 ± 0.93 mm in the control group ( p = 0.804). At 22 months, the mean MBL was 2.09 ± 1.03 mm in the treatment group and 1.58 ± 0.73 mm in the control group ( p = 0.339). No statistically significant differences in probing depth (PD) and bleeding on probing (BOP) were found at the 22 ‐month follow‐up as well. Soft tissue mean recession was observed in the control group (0.36 ± 0.84 mm), while no recession was found in the test group ( p = 0.2). Early implant soft tissue exposure occurred in 33% of test group participants, while none was observed in the control group ( p = 0.047). Conclusion One year after implant loading, no significant differences in marginal bone resorption were found between implants placed in ARP‐treated and naturally healed sites. However, ARP‐treated sites exhibited early implant soft‐tissue exposure, suggesting a possible impairment in soft tissue healing.