Hypoxic dental pulp stem cells-released succinate promotes osteoclastogenesis and root resorption.

Introduction: Clinical studies have shown that endodontically-treated nonvital teeth exhibit less root resorption during orthodontic tooth movement. The purpose of this study was to explore whether hypoxic dental pulp stem cells (DPSCs) can promote osteoclastogenesis in orthodontically induced inflammatory root resorption (OIIRR). Methods: Succinate in the supernatant of DPSCs under normal and hypoxic conditions was measured by a succinic acid assay kit. The culture supernatant of hypoxia-treated DPSCs was used as conditioned medium (Hypo-CM). Bone marrow-derived macrophages (BMDMs) from succinate receptor 1 (SUCNR1)-knockout or wild-type mice were cultured with conditioned medium (CM), exogenous succinate or a specific inhibitor of SUCNR1 (4c). Tartrate-resistant acid phosphatase (TRAP) staining, Transwell assays, qPCR, Western blotting, and resorption assays were used to evaluate osteoclastogenesis-related changes. Results: The concentration of succinate reached a maximal concentration at 6 h in the supernatant of hypoxia-treated DPSCs. Hypo-CM-treated macrophages were polarized to M1 proinflammatory macrophages. Hypo-CM treatment significantly increased the formation and differentiation of osteoclasts and increased the expression of osteoclastogenesis-related genes, and this effect was inhibited by the specific succinate inhibitor 4c. Succinate promoted chemotaxis and polarization of M1-type macrophages with increased expression of osteoclast generation-related genes. SUCNR1 knockout decreased macrophage migration, M1 macrophage polarization, differentiation and maturation of osteoclasts, as shown by TRAP and NFATc1 expression and cementum resorption. Conclusions: Hypoxic DPSC-derived succinate may promote osteoclast differentiation and root resorption. The regulation of the succinate-SUCNR1 axis may contribute to the reduction in the OIIRR.

A novel periodontal endoscopy-aided non-incisional periodontal regeneration technique in the treatment of intrabony defects: a retrospective cohort study.

BACKGROUND: Gingival recession and post-operation discomfort are still a problem for patients receiving the periodontal regeneration surgery for intra-bony defects. To further reduce the trauma and the post-operation gingival recession, a novel periodontal endoscopy-aided non-incisional regeneration technique (NIT) was proposed in the treatment of intra-bony defects. METHODS: Retrospective analysis of 21 subjects treated with NIT and 21 subjects with periodontal endoscopy-aided scaling and root planing (PSRP) at baseline and 1-year evaluation was conducted. After removing the subgingival calculus and granulation tissue, bone grafting materials were placed into intrabony defects with the assistance of a gingival retractor in the NIT group. Probing depth (PD), gingival recession (GR), clinical attachment level (CAL), as well as the distance between bone crest (BC) level and base of the defect (BD) (intrabony defect depth, IBD) were evaluated at baseline and 1 year after treatment. RESULTS: At 1-year follow-up, the value of CAL, PD and IBD were statistically significant different compared with baseline in both two groups (p<0.001). CAL gain (p = 0.012) and PD reduction (p = 0.004) was greater in the NIT than PSRP. However, no difference in the IBD reduction was found between the NIT group and PSRP. Better CAL gain and PD reduction was achieved in the 1-year term in the NIT when compared with PSRP. CONCLUSION: NIT have resulted in significant gains in both clinical and radiographic parameters. NIT might be utilized as an alternative of the surgical treatment for periodontal intrabony defects. TRIAL REGISTRATION: This clinical trial registration was registered retrospectively (August 3, 2023) and the number is ChiCTR2300074317.

Clinical and radiographic evaluation of Bio-Oss granules and Bio-Oss Collagen in the treatment of periodontal intrabony defects: a retrospective cohort study.

OBJECTIVE: This retrospective study aimed to analyze the clinical efficacy of two regenerative surgical methods - Bio-Oss granules combined with barrier membranes and Bio-Oss Collagen alone - and to help clinicians achieve better periodontal regeneration outcomes in the specific periodontal condition. METHODOLOGY: Patients who underwent periodontal regeneration surgery from January 2018 to April 2022 were retrospectively screened, and their clinical and radiographic outcomes at 6 months postoperatively were analyzed. The probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival recession (GR), distance from the cemento-enamel junction to the bottom of the bone defect (CEJ-BD), and depth of intrabony defects (INFRA) were recorded before the operation (T0) and 6 months after it (T1), and subsequently compared. RESULTS: In total, 143 patients were included - 77 were placed in the Bio-Oss group and 66 were placed in the Bio-Oss Collagen group. All indicators, including PD and CAL at T1, showed significant differences compared to baseline, for both groups (P<0.001). PD reduction was greater in the group receiving the Bio-Oss Collagen treatment (P=0.042). Furthermore, in cases when the baseline PD range was 7-11 mm and the age range was 35-50 years, PD reduction was more significant for patients receiving the Bio-Oss Collagen treatment (P=0.031, 0.023). A linear regression analysis indicated that postoperative PD and CAL were positively correlated with baseline values, and that the efficacy tended to decrease with increasing age. CONCLUSION: Both the use of Bio-Oss Collagen alone and the use of Bio-Oss granules combined with barrier membranes resulted in significant effects in the treatment of periodontal intrabony defects. The Bio-Oss Collagen treatment generated more improvements in PD than the Bio-Oss granules combined with barrier membranes, particularly within the baseline PD range of 7-11 mm and the 35-50 years age group. Additionally, age was the main factor influencing the effectiveness of regenerative surgery for intrabony defects: older individuals exhibited fewer improvements.

Clinical and radiographic evaluation of Bio-Oss granules and Bio-Oss Collagen in the treatment of periodontal intrabony defects: a retrospective cohort study

Abstract Objective This retrospective study aimed to analyze the clinical efficacy of two regenerative surgical methods — Bio-Oss granules combined with barrier membranes and Bio-Oss Collagen alone — and to help clinicians achieve better periodontal regeneration outcomes in the specific periodontal condition. Methodology Patients who underwent periodontal regeneration surgery from January 2018 to April 2022 were retrospectively screened, and their clinical and radiographic outcomes at 6 months postoperatively were analyzed. The probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival recession (GR), distance from the cemento-enamel junction to the bottom of the bone defect (CEJ-BD), and depth of intrabony defects (INFRA) were recorded before the operation (T0) and 6 months after it (T1), and subsequently compared. Results In total, 143 patients were included — 77 were placed in the Bio-Oss group and 66 were placed in the Bio-Oss Collagen group. All indicators, including PD and CAL at T1, showed significant differences compared to baseline, for both groups (P<0.001). PD reduction was greater in the group receiving the Bio-Oss Collagen treatment (P=0.042). Furthermore, in cases when the baseline PD range was 7-11 mm and the age range was 35-50 years, PD reduction was more significant for patients receiving the Bio-Oss Collagen treatment (P=0.031, 0.023). A linear regression analysis indicated that postoperative PD and CAL were positively correlated with baseline values, and that the efficacy tended to decrease with increasing age. Conclusion Both the use of Bio-Oss Collagen alone and the use of Bio-Oss granules combined with barrier membranes resulted in significant effects in the treatment of periodontal intrabony defects. The Bio-Oss Collagen treatment generated more improvements in PD than the Bio-Oss granules combined with barrier membranes, particularly within the baseline PD range of 7-11 mm and the 35-50 years age group. Additionally, age was the main factor influencing the effectiveness of regenerative surgery for intrabony defects: older individuals exhibited fewer improvements.