[A prospective case series study of alveolar ridge preservation using different bone graft materials in molars with severe periodontitis].

<b>Objective:</b> To compare the clinical effects of using xenogenic bone graft materials with or without collagen components for tooth micro crestal flap-alveolar ridge preservation (MCF-ARP) at molars with severe periodontitis. <b>Methods:</b> This study included patients who visited Department of Periodontology, Peking University School and Hospital of Stomatology from May to November 2023 due to severe periodontitis, requiring tooth extraction and planning for implant-retained prostheses. A total of 24 molars from 24 patients with severe periodontitis were assigned into two groups: the deproteinized bovine bone mineral (DBBM) group and the DBBM with collagen (DBBM-C) group. Twelve affected teeth from 12 patients were included in each group. Both groups underwent minimally invasive tooth extraction and MCF-ARP, with DBBM and DBBM-C implanted in the extraction socket, respectively. Cone beam CT (CBCT) was performed before and 6 months after the surgery for assessing changes of hard tissue. Intraoral scanning was performed before and at 2 weeks, 1 month, 3 months, and 6 months after the surgery for assessing soft tissue contour changes and patterns in both groups. <b>Results:</b> After 6 months of healing, the central bone height increased by (8.35±2.25) mm in the DBBM group and (7.70±2.36) mm in the DBBM-C group. The ridge width at 1 mm apically from the higher bone crest increased by 6.43 (-0.76,7.96) mm in the DBBM group and 6.01 (5.41,7.90) mm in the DBBM-C group. There was no statistically significant difference in the changes of bone height and width between the two groups (all <i>P</i>>0.05). In terms of soft tissue contour changes, although the buccal contour collapses were less in the DBBM-C group, the two groups showed no statistically significant difference (all <i>P</i>>0.05). <b>Conclusions:</b> Within the limitations of this study, it was demonstrated that the clinical effects of MCF-ARP using xenogenic bone graft materials with or without collagen components in molars with severe periodontitis were comparable.