Background During the obturation procedure, sealer extrusion occurs in some cases. iRoot SP is a kind of bioceramic sealer with superior physicochemical and biological properties. This article reports the outcome of iRoot SP extrusion in root canal treatment and the potential factors associated with the outcome. Methods Ninety-nine patients and one hundred and eighty-five teeth treated between 2014 and 2020 were included in this retrospective study. All of the cases were filled with a single-cone technique and the iRoot SP sealer. The minimum follow-up visit period was 1 year. The outcome was evaluated by clinical examination and radiographic examination at recall and was classified as healed, healing (success), or not healed (failure). Results The overall success rate of all teeth was 96.8%. The success rate of adequately filled teeth was 97.3%, while that of iRoot SP extrusion was 95.8%; the difference was not statistically significant. Factors such as gender, age, tooth position, follow-up visit period, size of periapical lesion, treatment type and extruding sealer amount had no influence on the outcome of iRoot SP extruded teeth. Conclusions The results suggested that iRoot SP extrusion has no adverse effect on the outcome of root canal treatment, which may contribute to the endodontic treatment.

FUN14 domain-containing 1 (FUNDC1) is a receptor that has been previously reported to activate hypoxia-induced mitophagy. However, the potential role of FUNDC1 in the pathophysiology of dental pulp diseases remains unknown. Therefore, present study first collected tissue specimens from patients with pulpitis and from healthy individuals. The results of reverse transcription-quantitative PCR and immunohistochemical staining revealed markedly increased FUNDC1 and hypoxia-inducible factor-1 alpha expression in pulpitis tissue specimens compared with those from healthy individuals. To provide a theoretical basis for the study of the occurrence, development and reparative mechanisms in the dental pulp after tissue injury, the present study then investigated the role of hypoxia-induced mitophagy in the regulation of proliferation, migration and odontoblastic differentiation in human dental pulp cells (HDPCs), in addition, to the possible involvement of FUNDC1. The surface markers and multipotent differentiation capabilities of HDPCs were performed by flow cytometry (surface markers), alizarin red (osteogenic capabilities), alcian blue (chondrogenic capabilities) and oil red O (adipogenic capabilities). Following culture under hypoxia conditions (1% O-2) for varying time periods, the proliferation, migration and odontoblastic differentiation of HDPCs were measured using Cell Counting Kit-8, wound healing and Transwell migration assays, alkaline phosphatase staining and activity tests and western blotting (runt-related transcription factor 2, collagen I, osterix and osteopontin), respectively. Immunofluorescence and western blotting were performed to measure the expression levels of hypoxia-inducible factor-1 alpha, pro-fission dynamin-related protein 1, mitochondria-related proteins translocase of inner mitochondrial membrane 23 and translocase of outer mitochondrial membrane 20, in addition to those of autophagy markers (p62, LC3II, Beclin-1 and autophagy-related 5). Transmission electron microscopy was also used to image the autophagosomes and mitochondrial morphology. In addition, to study the functional role of FUNDC1, its expression was silenced by liposome-mediated transfection with small interfering RNA into HDPCs. Compared with those in HDPCs cultured under normoxic conditions (21% O-2), the ability of autophagy in HDPCs cultured under hypoxic conditions for 18 h was markedly increased, whilst the proliferation, migration and odontoblastic differentiation were also enhanced. Increased numbers of autophagosomes could also be observed in the hypoxic group. However, FUNDC1 knockdown in HDPCs reversed the aforementioned effects. Overall, data from the present study suggest that hypoxia can promote the proliferation, migration and odontoblastic differentiation of HDPCs, where the underlying mechanism may be associated with the activation of mitophagy downstream of FUNDC1.

目的 通过回顾性分析,研究iRoot SP辅助单尖充填法及多种预后因素对根管治疗临床效果的影响.方法 从2014—2018年于中山大学附属口腔医院接受根管治疗且能追踪复查的患者中,选择使用iRoot SP辅助单尖充填后且复诊时间为1年以上患者的110颗患牙纳入分析.根据每颗患牙复诊时临床和影像学检查结果,将患牙的预后分为成功和失败两组.使用连续性修正卡方检验和Fisher精确检验,对术前是否存在根尖阴影、术前根尖阴影的直径大小和有无封闭剂超充等8项可能影响iRoot SP单尖充填临床效果的预后因素进行统计分析.结果 110颗接受iRoot SP单尖充填治疗的患牙总体成功率为95.5％.其中,83颗术前有根尖阴影患牙的治疗成功率为96.4％,68.7％为已愈合;27颗术前无根尖阴影患牙的治疗成功率为92.6％.术前有根尖阴影和无根尖阴影患牙的治疗成功率差异无统计学意义(χ2=0.084,P=0.772).术前根尖阴影直径小于或等于5 mm的患牙共53颗,治疗成功率为98.1％;而阴影直径大于5 mm的患牙共30颗,治疗成功率为93.3％.两组患牙治疗成功率的差异无统计学意义(χ2=0.259,P=0.611).44颗封闭剂超充患牙的治疗成功率为97.7％,患牙有无iRoot SP超充的治疗成功率差异也无统计学意义(χ2=0.218,P=0.640).结论 iRoot SP单尖充填法是可行的根管充填技术.

牙髓治疗,特别是牙髓再生治疗后出现牙齿内源性着色是临床治疗经常遇到的问题.牙髓治疗过程中出现在髓室内的血液,残留于髓室的根管消毒药物、根管充填用封闭剂及冲洗剂等均可能导致牙齿内源性着色.本文对牙髓治疗后硅酸盐水门汀、抗生素、次氯酸钠、乙二胺四乙酸和氢氧化钙等材料引起牙齿内源性着色的具体机制、预防方法和内源性着色后处理的研究现状作一综述.