INTRODUCTION AND AIMS:Periodontal ligament stem cells (PDLSCs) from deciduous teeth (DePDLSCs) can perceive and respond to mechanical signals upon exposure to various environments. The effects of mechanical stress on the biological characteristics and metabolism of DePDLSCs were investigated using in vitro stress loading. METHODS:DePDLSCs were subjected to mechanical stresses of different strengths. Cell proliferation, expression of osteogenic/osteoclastic factors, apoptosis, and oxidative stress levels were evaluated using CCK-8 assays, alkaline phosphatase staining, real-time PCR, flow cytometry, and malondialdehyde and superoxide dismutase assays. Liquid chromatography-mass spectrometry was used to perform nontargeted metabolomic detection and analysis. RESULTS:Under stresses of 75 and 150 kPa, the expression of osteogenesis-related factors OPG, ALP, and RUNX2 decreased, and the ratio of RANKL/OPG significantly increased. A pressure of 150 kPa induced oxidative stress and caused a significant increase in cell apoptosis. Among the differential metabolites screened from the 150 kPa group, spermine, spermidine, ceramide, phosphatidylethanolamine, lysophosphatidylethanolamine, linoleic acid, and docosatrienoic acid were the most significantly upregulated. The metabolites screened from the 75 kPa group were mainly related to glycerophospholipid and sphingolipid metabolism, oxidative phosphorylation, and mineral absorption, which were common pathways affected in both experimental groups. CONCLUSION:A certain degree of mechanical stress can inhibit the proliferative activity and osteogenic differentiation of DePDLSCs, enhance their osteoclast-inducing ability, and cause elevated levels of cell apoptosis and oxidative stress. The metabolic expression profile of DePDLSCs changed significantly under stress. Understanding changes in cellular activity and metabolic reactions may provide an experimental basis for elucidating the role of mechanical stress in root resorption and periodontal tissue remodelling of deciduous teeth. CLINICAL RELEVANCE:Mechanical stress may affect periodontal tissue remodeling and root resorption of DePDLSc.

Aim or purpose: Dental avulsion presents significant treatment challenges, especially in immature permanent teeth. Regenerative endodontic treatment (RET) has emerged as a promising biological approach to restore pulp vitality and promote root development. This systematic review and meta-analysis evaluated RET outcomes in avulsed immature teeth. Materials and methods: We conducted electronic searches in PubMed, Web of Science, Science Direct, Cochrane Library, and Scopus to gather relevant studies. The selected studies were analyzed by the reviewers using a standardized data extraction form for a simplified extraction process. Data extraction was conducted independently by the reviewers. Results: Of the 1566 records found, nine studies were eligible for systematic review, and seven were eligible for meta-analysis. The point estimate for the rate of tooth survival was 71% (95% confidence interval [CI], 57%-85%). Root lengthening was reported in all seven studies, with a total sample of 23 teeth; 96% (95% CI, 85%-100%), Root width was reported in seven studies, with a total sample of 23 teeth; 98% (95% CI, 87%-100%), Apical Closure Apical narrowing was reported in seven studies, with a total sample of 23 teeth; 92% (95% CI, 81%-100%), Periapical radiolucency was reported in three studies, with a total sample of 23 teeth; 78% (95% CI, 67%-89%). Conclusions: RET may offer benefits for managing avulsed immature permanent teeth, including improvements in root wall lengthening and thickening, periapical lesion healing, and apical closure formation. Regenerative therapy might be a promising treatment option for restoring the health and function of avulsed immature permanent teeth.

Background Indirect pulp capping (IDPC) is a preferred treatment for pulp preservation in primary teeth. However, the survival rate of IDPC in primary teeth and impact factors is still equivocal. Aims To evaluate the survival rate of IDPC in primary teeth with a deep carious lesion approximating the pulp but without irreversible pulpitis or periapical disease. Methods The medical records of children who were diagnosed with severe early childhood caries (S-ECC) and received IDPC under dental general anaesthesia from January 2015 to December 2020 were screened and collected. The shared frailty model was used to explore potential factors affecting the success rate of IDPC in primary teeth. Results There were 352 children with S ECC and 1,197 teeth were included in the study. A total of 47 children had IDPC that failed in the follow-up period (67 teeth). The survival rates of the teeth treated with IDPC at 48 months was 82.3%. The risk of IDPC primary tooth treatment failure in mandibular teeth was 2.35 times that of maxillary teeth and risk of failure in lesions with mesial surface involvement was 2.76 times higher than those without mesial surface involvement. Conclusion In the present study, the overall survival rate of IDPC did not decrease remarkably with time, regardless of anterior or posterior teeth. The tooth arch position and whether the mesial surface was involved in the carious lesion were found to influence the outcome of IDPC.

OBJECTIVES:This study aimed to evaluate the clinical application value of in-situ crown reattachment technique combined with pulpotomy in the treatment of complicated crown-root fractures in young permanent anterior teeth. METHODS:A prospective study was conducted on 50 children with complicated crown-root fractures in young permanent anterior teeth, who were treated at the Pediatric Dentistry Department, Hospital of Stomatology, Xi'an Jiaotong University from June 2023 to June 2024. All patients underwent in-situ crown reattachment technique combined with pulpotomy. Clinical examinations, radiographic evaluations, and subjective satisfaction surveys (using a Likert scale of 1-10) were conducted at 1, 6, and 12 months postoperatively. Data were analyzed using SPSS 23.0. RESULTS:The loss-to-follow-up rate was 12% (6/50), with 44 cases completing the 12 months of evaluation. The clinical success rate was 93.18% (41/44), and the radiographic success rate was 97.73% (43/44). The subjective satisfaction scores showed a significant improvement in masticatory function from 7.03±0.52 at 1 month to 8.07±0.92 at 12 months postoperatively (P<0.05), whereas the scores for aesthetics, comfort, and quality-of-life impact showed no statistically significant differences (P>0.05). CONCLUSIONS:In-situ crown reattachment technique combined with pulpotomy effectively treats complicated crown-root fractures in young permanent anterior teeth, demonstrating a high short-term clinical success rate, significantly improved masticatory function, and minimally invasive preservation of pulp vitality and root development potential. This technique provides an optimized treatment option for dental trauma in children, although its long-term efficacy requires further validation.

Dental treatments for children and adolescents have unique clinical characteristics that differ from dental care for adults in terms of children's physiology, psychology, and behavior. These differences impose specific requirements on the application of local anesthesia in pediatric dental procedures. This article presents expert consensus on the principles of local anesthesia techniques in pediatric dental therapies, including the use of common anesthetic drugs and dosage control, safety and efficacy evaluation, and prevention and management of complications. The aim is to improve the safety and quality of pediatric dental treatments and offer guidance for clinical application by dentists.

Aim This scoping review assessed the performance of regenerative endodontic treatment (RET) in avulsed immature permanent teeth, which presented a significant challenge in dental trauma management. This scoping review aims to evaluate RET outcomes, protocols, complications, and effectiveness in avulsed immature permanent teeth, identifying research gaps to advance clinical application. Materials and methods The review encompassed a comprehensive search of PubMed, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Science Direct, spanning over 20 years, supplemented by snowball searching. Full-text articles in any language were eligible if they were randomized/non-randomized clinical trials or prospective/retrospective cohort studies with at least 12 months of follow-up, following the PCC framework. Data were extracted using standardized forms, including author(s), publication year, study origin, aim, sample size, intervention protocol, follow-up, outcome measures, and measurement methods. Results Of the 1623 records reviewed, 14 studies met the inclusion criteria. These studies, involving 82 avulsed immature anterior teeth, demonstrated an overall success rate of 44 % (36/82) over a minimum 12-month follow-up, with success defined by periapical radiolucency resolution and positive root development. The included studies showed significant variability in RET protocols, with calcium hydroxide as the primary intracanal medicament, blood clot as the main scaffold, and 17 % (Ethylenediaminetetraacetic acid) EDTA with saline as the most common irrigation method. Notably, extra-alveolar time and storage conditions significantly influenced outcomes, with replantation within 60 min using a physiological medium yielding the best results. Conclusion While RET demonstrates approximately 44 % success in treating avulsed immature teeth, the variability in treatment protocols and the limited sample sizes in current studies highlight the need for more extensive research and standardized protocols to validate its use by dental practitioners.

Background: Dens invaginatus (DI) is a developmental dental anomaly whose clinical manifestations and treatment plans vary depending on its type and severity. Type III DI is one of the primary pathways of periradicular infection. This report presents a series of cases of endodontic treatment of type III DI with periradicular lesions in young permanent teeth. Cases: Four cases with type III coronal DI (CDI) and periradicular lesions were included. Following oral and radiographic examinations, the patients underwent endodontic treatment. Among them, three cases accepted endodontic access to invaginations, chemomechanical instrumentation, medication, obturation, and periodontal surgical procedures when clinically indicated. The other patient also underwent main root canal treatment simultaneously. After long-term follow-up (1-3 years), all patients were free of clinical symptoms or positive clinical signs, with evidence of reduced or resolved periapical radiolucency and normal pulp vitality. Conclusions: By disinfecting and obturating the invagination canal, the pulp vitality of the affected type III CDI tooth can be preserved with minimal damage to the tooth structure, thereby promoting further root development in young permanent teeth.

This study aimed to illustrate the biological behavior and changes in cell function during the progression of apical periodontitis in deciduous teeth and to explore the underlying molecular mechanism. Deciduous teeth periodontal ligament stem cells (DePDLSCs) were derived and their identity was confirmed. The viability, inflammation, and osteogenic ability of cells were tested by exposing them to various concentrations of lipopolysaccharide (LPS) (0-100 μg/mL) using the cell counting kit-8 (CCK-8) assay, reverse transcription polymerase chain reaction (real-time PCR), alkaline phosphatase (ALP) staining, and ALP activity assay. In addition, osteogenic-induced cells with and without 10 μg/mL LPS were harvested for high-throughput sequencing. Based on sequencing data, proinflammatory factors and ALP expression were measured after interference with the PI3K-AKT signaling pathway activator, 740Y-P. LPS biphasically affected the proliferation and osteogenesis of DePDLSCs. Low concentrations of LPS showed stimulatory effects, whereas inhibitory effects were observed at high concentrations. Sequencing analysis showed that the PI3K-AKT signaling pathway was significantly downregulated when DePDLSCs were treated with 10 μg/mL LPS. The LPS-induced inflammation and osteogenesis inhibition of DePDLSCs were partially rescued by 740Y-P treatment. In conclusion, LPS affected DePDLSCs proliferation and osteogenesis in a biphasic manner. Moderate activation of PI3K-AKT signaling pathway was beneficial for osteogenic differentiation and anti-inflammatory effect in DePDLSCs. This research may provide etiological probes for apical periodontitis and its treatment.

Objectives: To evaluate and compare the effectiveness of Endoflas and Zinc Oxide Eugenol (ZOE) as root canal filling materials (RCFMs) for the pulpectomy of deciduous teeth by analyzing multiple clinical and radiographic success and failure follow-ups in previously published studies. Data: All clinical studies that investigated the pulpectomy of the deciduous teeth of children aged 3-9 years. Sources: The databases used for source identification included MEDLINE (via PubMed), Scopus, Web of Science, and the Cochrane Library. No limitations were imposed on the publication year or language. The selection of studies and extraction of relevant study characteristics were conducted from December 26, 2021, to September 7, 2023. Additionally, the risk of bias (RoB) in the included studies was evaluated by using a RoB instrument (RoB 2). Eligible studies were then combined, and a random-effects model was applied by using the maximum likelihood estimations of log risk ratios and their corresponding 95% confidence intervals. Study selection: Of the 3913 records found in the abovementioned databases, nine were eligible for systematic review and eight were eligible for meta-analysis. The studies included 628 pulpectomies of deciduous molar teeth in children. The overall results showed that compared with Endoflas, ZOE was associated with a higher risk ratio for clinical evaluation (LOG[RR] = 0.06, CI 0.03-0.09, p-value 0.001) and radiographic evaluation (LOG[RR] = 0.68, CI 0.35-1.00, p-value 0.001). This association was highly significant at 6- and 9-month follow-ups. Conclusion: Compared with ZOE, Endoflas was associated with a lower risk of the clinical and radiographic failure of deciduous teeth pulpectomy and a 6%-6.8% higher risk ratio, especially at 6- and 9-month follow-ups. Clinical significance: This study suggests the superiority of Endoflas over ZOE as an RCFM for deciduous teeth.

Objective. Currently, the summaries of research on periodontal ligament stem cells (PDLSCs) are mainly reviews, and the systematic evaluation of all relevant studies is lacking. The aim of our study was to reveal the research status and developmental trends of PDLSCs using bibliometric analyses. Methods. Publications on PDLSC from 2004 to 2023 in the PubMed database were searched and then screened according to certain inclusion and exclusion criteria. Two researchers browsed the included papers and recorded information such as the research type and research model. The VOSviewer software was used to analyze the distribution of authors, journals, and institutions. The contents and directions of PDLSC research were summarized by analyzing high-frequency keywords. The CiteSpace software was used to monitor burst words, determine hot factors, and indicate developmental trends. Results. During the past two decades, the number of studies on PDLSCs increased. China published the most related papers. The primary type of article was basic research. Among core journals, the Journal of Periodontal Research had the highest number of publications. The Fourth Military Medical University (China) was leading in the number of articles on PDLSCs. Research topics mainly included mechanism of periodontal diseases, tissue engineering and regeneration, biological characteristics of PDLSCs, and comparison with other stem cells. Infectious inflammation and mechanical stimulation were important pathological conditions and research topics. Conclusion. The research of PDLSCs is still in a rapid development stage. Our study provides new insights into the current research status and future trend in this field.

OBJECTIVES:This study aims to retrospectively evaluate the survival rate of pulpectomy performed under dental general anesthesia (DGA) through long-term follow-up and to explore the risk factors associated with treatment failure.METHODS:The medical records of the children who were diagnosed with S-ECC and received pulpectomy treatment under general anesthesia (GA) from 1 August 2014 to 1 December 2019, in the Stomatological Hospital of Xi'an Jiaotong University, were collected. Two dentistry postgraduates extracted the necessary information and filled in a predesigned excel form. Survival analysis was performed using the Kaplan-Meier method. The shared frailty model was used to explore possible factors affecting the success rate of pulpectomy in primary teeth.RESULTS:A total of 381 children (mean age 3.49 ± 0.90) with S-ECC and 1220 teeth were included in the study, including 590 primary anterior teeth and 630 primary molars. The overall 35-month survival rate was 38.5%, which was 52.9% for anterior teeth and 31.1% for molars. The overall median survival time was 31 months, in which anterior teeth were 35 months and molars were 26 months. The older the children were, the greater the risk of treatment failure (HR 1.56, 95% CI 1.09, 2.24). The risk of pulpectomy failure of primary molars was 1.9 times that of primary anterior teeth (95% CI 1.36, 2.65) and the teeth with abnormal radiological findings before treatment was 1.41 times higher than that of teeth without imaging abnormalities (95% CI 1.74, 3.36).CONCLUSION:The survival rate of primary tooth pulpectomy is acceptable but decreased gradually with time. The failure rate of pulpectomy in primary molars is higher than that of primary anterior teeth. When the primary caries has extended to the pulp and resulted in a nonvital lesion, pulpectomy could be an option for maximum retention of the primary tooth.

Objective Dental avulsion in permanent teeth is considered as one of the most severe types of traumatic dental injuries.Few studies assess the knowledge on management of dental avulsion in un-dergraduate medical students,who would probably provide emergency treatment for patients.This study aims to evaluate the knowledge and attitudes of medical students in China regarding dental avulsion,emergency procedures and awareness about prevention of such injuries.Methods A non-probability convenience sampling methodology was employed for sample selection.A specific questionnaire regarding knowledge,experiences and behaviors following dental avulsion was distributed to the first and fifth year students from Xi'an Jiaotong University Health Science Center and Xi'an Medical University in May 2022.Chi-square test was used for data analysis,with a significance level set at P＜0.05.Results 1 095 undergraduate medical students(568 first year students,527 fifth year students)completed the questionnaire.The incidence of tooth avulsion reported by participants was 2.7％,59.3％of first year students and 66.2％of fifth year students chose the proper emergency management for avulsed tooth.29.3％of all students selected the appropriate transportation medium for avulsed tooth,with a higher accuracy among fifth year students.Less than 40％of students chose the correct replantation time and cleaning method.There were not statistically differences in accuracies for emergency management of avulsion,replantation time and rinsing method between two grades.Awareness rates of mouth guard and tooth replantation were low.More than 56.6％of the medical students claimed that they never received any knowledge about dental injuries.Conclusion The results suggest that knowledge of dental avulsion among medical students in China was insufficient.It is necessary to enhance dental trauma education for medical students.

Fluoride can be widely ingested from the environment, and its excessive intake could result in adverse effects. Dental fluorosis is an early sign of fluoride toxicity which can cause esthetic and functional problems. Though apoptosis in ameloblasts is one of the potential mechanisms, the specific signal cascade is in-conclusive. High-throughput sequencing and molecular biological techniques were used in this study to explore the underlying pathogenesis of dental fluorosis, for its prevention and treatment. A fluorosis cell model was established. Viability and apoptosis rate of mouse ameloblast-derived cell line (LS8 cells) was measured using cell counting kit-8 (CCK-8) assay and flow cytometry analysis. Cells were harvested with or without 2-mM sodium fluoride (NaF) stimulation for high-throughput sequencing. Based on the sequencing data, subcellular structures, endoplasmic reticulum stress (ERS), and apoptosis related biomarkers were verified using transmission electron microscopy, quantitative real-time polymerase chain reaction, and Western blotting techniques. Expression of ERS markers, apoptosis related proteins, and enamel formation enzymes were detected using Western blotting after addition of 4-phenylbutyrate (4-PBA). NaF-inhibited LS8 cells displayed time- and dose- dependent viability. Additionally, apoptosis and morphological changes were observed. RNA-sequencing data showed that protein processing in endoplasmic reticulum was obviously affected. ERS and apoptosis were induced by excessive NaF. Downregulation of kallikrein-related peptidase 4 (KLK4) was also observed. Inhibition of ERS by 4-PBA rescued the apoptotic and functional protein changes in cells. Excessive fluoride induces apoptosis by activating ERS, which is mediated by GRP-78/PERK/CHOP signaling. Key proteinase is present in maturation-stage enamel; KLK4 was also affected by fluoride, but rescued by 4-PBA. This study presents a possibility for therapeutic strategies for dental fluorosis, while further exploration is required.

ObjectiveThis study aimed to retrospectively describe the unplanned retreatment of dental general anesthesia (DGA) in children with severe early childhood caries (S-ECC) and explore potential factors that may influence the outcome of DGA treatment. MethodsMedical records of children with S-ECC who received DGA treatment were screened, and necessary data were extracted. The Kaplan-Meier method and Cox proportional hazards model were used to estimate the DGA survival rate and explore the potential factors affecting the success rate of DGA treatment. ResultsMedical records of 852 children were included; 509 (59.7%) children with 1,212 (10.7%) teeth underwent unplanned retreatment. Restoration failure (30.12%) and new caries (29.46%) accounted for the most significant proportion of all failures. The median survival times were 510 and 1,911 days at the child and tooth levels, respectively. Unplanned retreatment risk was associated with the age of S-ECC children, frequency of follow-up, and fluoride application (hazard ratio = 0.97, 0.78, 0.69, P < 0.001). ConclusionThe treatment outcome of DGA administered to children with S-ECC was satisfactory at the tooth level from the perspective of the incidence of unplanned retreatment. Restoration failure was the main reason for the high unplanned retreatment rate. Strategies for a better outcome of DGA include improving the professional knowledge and skills of pediatric dentists and enhancing compliance of parents/patients. Health education and regular topical fluoride application may improve the success rate of DGA treatment.

目的 检测无龋儿童和不同程度患龋儿童唾液中变异链球菌含量及钙离子浓度,分析其差异,探索其与低龄儿童龋(ECC)发病率之间的联系,为后续评估龋病风险提供依据.方法 选取90名不同患龋程度的4～5岁儿童,进行龋病检查和非刺激性唾液样本收集,检测样本钙离子浓度;剩余唾液采用实时荧光定量聚合酶链式反应技术检测变异链球菌的数量.结果 无龋组、轻度以及重度ECC组唾液钙离子浓度均值分别为0.81、0.92、0.99 mmol/L;变异链球菌的数量均值分别0.91×105、1.72×105、7.04×105 CFU/mL.结论 变异链球菌的数量是唾液中预测低龄儿童患龋风险最重要的指标,2.00×105 CFU/mL很可能是筛查重度ECC患儿的基线水平.

Background/Objective: To retrospectively analyze the characteristics, tendencies, and success rates of dental treatments for severe early childhood caries (SECC) under general anesthesia (GA) in in northwest China. Study design: Children diagnosed with SECC were included in this retrospective study. From January 2015 to December 2018, they received dental treatment under GA at Affiliated Stomatology Hospital of Xi'an Jiaotong University. Demographic information, caries status and treatment characteristics were collected from electronic medical record system. Success rates of different treatments at 6-month and 12-month follow up were also analyzed. Results: A total of 846 children (477 male, 369 female) received dental treatment under GA. The case number was increased from 148 in 2015 to 278 in 2018. There were 81.2% and 70.8% of the children participated the 6-month and 12-month follow up. SSC and pulpotomy was the most successful restorations and pulp therapy, with the success rate of 97.09% and 93.98% in 12-month follow up, respectively. The use of crown restorations (including composite resin crown and stainless steel crown) and pulp reservation therapies (including indirect pulp therapy and pulpotomy) were significantly increased while composite resin filling and pulpectomy decreased during 2015 to 2018. Conclusion: There has been an increasing demand for dental treatment under GA for children with SECC in northwest China, with a trend toward younger ages. With better clinical outcomes, crown restorations and pulp reservation therapies were the fastest-growing treatments under GA.

目的 分析影响乳磨牙间接牙髓治疗预后的相关因素.方法 回顾性分析2018年1月～2019年1月收治的90例(126颗)乳磨牙间接牙髓治疗患儿临床资料,根据治疗18个月后预后情况分为失败组(n=25颗)、成功组(n=101颗).从性别、年龄、牙位、充填体材料、间接盖髓剂种类、龋坏侵犯牙面情况等方面采用Cox回顾分析影响乳牙间接牙髓治疗长期预后的危险因素.采用Kaplan-Meier法分析不同龋坏侵犯牙面的累计生存情况.结果 龋坏侵犯牙面数量是影响乳牙IPT治疗的预后的单因素(P＜0.05);龋坏侵犯牙面数量是影响乳牙IPT治疗的预后的独立危险因素(P＜0.05);18个月随访期间,48颗面洞患牙累计生存46颗,18个月累计生存率95.83％,46颗邻面洞患牙累计生存40颗,18个月累计生存率86.96％,32颗邻颊面洞患牙累计生存15颗,18个月累计生存率46.88％,不同龋坏侵犯牙面数量患牙生存情况比较差异有统计学意义(P＜0.05).结论 龋坏侵犯牙面数量越多,深龋乳磨牙接受间接牙髓治疗后长期预后越不佳.

目的:体外比较单支锉ProTaper Sx和不锈钢K锉预备乳牙根管的时间和根尖推出物量.方法:门诊收集离体乳牙,经截冠、分根后,按远中根管、近中根管、前牙根管、腭根管、近颊根管及远颊根管六种根管类型各收集16个,共96个.将每种类型根管随机均匀分配至Sx组(n=48)和K锉组(n=48).分别用ProTaper Sx和不锈钢K锉进行根管预备,各根管均用10 mL 0.2％氯己定溶液冲洗,记录预备时间、测定根尖推出碎屑量和根尖渗出冲洗液量,进行统计学分析.结果:K锉组(328.8s)的预备时间是Sx组(180.9 s)的近1.8倍,差异有统计学意义(P<0.05).两种器械均会造成一定的根尖推出物,但推出物的量不同.Sx组的根尖推出碎屑量和根尖渗出冲洗液量(0.00128±0.00056)g;(0.00614±0.00183)g均低于K锉组(0.00345±0.00124)g;(0.02930±0.01879)g,差异均有统计学意义(P<0.05).结论:与不锈钢K锉相比,单支锉ProTaper Sx预备乳牙根管具有预备时间短、根尖推出物量少的特点.

目的 体外培养人乳牙牙周膜干细胞,建立符合实验设计需要的人乳牙根尖周炎细胞模型.方法 采用酶解组织块法培养人乳牙牙周膜干细胞,连续梯度稀释法进行纯化,流式法鉴定细胞表面标记物,检测其多向诱导分化能力.在培养基中加入不同终浓度(0.1,0.075,0.05,0.025,0.01μg/ml)的大肠杆菌脂多糖,通过检测细胞活性及炎症因子表达,选择合适的大肠杆菌脂多糖浓度.结果 酶解组织块法可获得成集落状生长的人乳牙牙周膜干细胞,流式鉴定高表达CD146、STRO-1、CD105、CD90、CD29,低表达CD45、CD34,细胞成骨、成脂诱导后分别对茜素红、油红O染色阳性.0.05μg/ml的大肠杆菌脂多糖不影响细胞增殖活性(P>0.05),能显著提高炎症因子IL-1β、TNF-α、IL-6的mRNA和蛋白表达水平(P<0.05).结论 0.05μg/ml的大肠杆菌脂多糖可作为诱导人乳牙牙周膜干细胞炎症模型的适宜浓度.

BACKGROUND/AIM:Injuries to the primary dentition affect children's esthetics, function, and mental health. They may also affect the development of the permanent teeth. The knowledge of dentists about deciduous tooth trauma is rarely evaluated. The aim of this study was to evaluate the knowledge and attitude of dentists in China regarding traumatic dental injuries to primary teeth.MATERIAL AND METHODS:A self-administered online questionnaire containing questions on demographic data and knowledge based on a clinical scenario was given to a purposive sample of dentists, recruited by a non-probability convenience sampling method. The chi-square test was used for statistical analysis, with the significance level set at P <.05.RESULTS:A total of 394 out of 409 dentists provided valid data. There was no significant difference in demographic data. Questions about the treatment of hard dental tissue injuries in primary teeth presented a correct-response rate of 66.4%, with the highest correct-response rate for enamel fracture (n = 368, 93.4%) and lowest for complicated crown-root fracture with pulp exposure (n = 104, 26.4%). Questions about treatment of luxation injuries in primary teeth presented a correct-response rate of 66.6%, with subluxation presenting the highest correct-response rate (n = 391, 99.2%). Factors associated with higher correct-response rates were specialist disciplines, educational qualifications, workplaces, experience of injured teeth treated, and educational experience about primary tooth trauma. No significant differences were found in the correct-response rates of dentists with different years of work experience. Lack of cooperation from children was considered a major obstacle for treatment. Special lectures and Internet courses were the most preferred methods of obtaining knowledge.CONCLUSION:The results suggest that it is necessary to enhance dental trauma education for dentists in China. More attention needs to be paid to trauma in primary dentition to ensure adequate treatment for traumatized primary teeth.