目的：以电子病历数据库为依托，观察乳磨牙牙髓切断术后预后情况，并对其影响因素进行分析。方法：在北京大学口腔医院电子病历数据库中，利用科研疾病数据库，检索2014年5月至2015年11月间于儿童口腔科进行三氧化物聚合体（mineral trioxide aggregate, MTA）乳磨牙牙髓切断术治疗的8 岁及以下患儿，选择无全身系统性疾病且规律随访时间超过1.5年、病历记录完整、在治疗前后均有影像学检查记录（X线片）的患儿为研究对象，收集患儿的病历信息和X线资料。根据术后临床及X线表现，将所有乳磨牙预后归为N、H、P0、PX、PY 5类，预后P0、PX、PY定义为失败。以患牙为单位，绘制生存曲线，用Cox比例风险回归模型分析影响患牙预后的因素。结果：共纳入115名患儿，初诊年龄为2.6~8.2 岁，平均（4.5±1.1）岁，共211 颗乳磨牙，平均随访时间为（880±154） ｄ。截止至2017年9月，术后有49 颗乳磨牙治疗失败，其中43 颗乳磨牙表现有影像学异常，如根尖周和（或）根分歧下病变、根管钙化、牙根内外吸收等，6 颗乳磨牙早失，只有14 颗患牙有明显的临床症状，如牙龈红肿、溢脓或者病理性松动。通过KaplanMeier法分析发现，牙髓切断术后的0.5年生存率为100%，1年时为98.5%，1.5 年时为92.9%，2年时为90.5%，2.5 年时为73.8%。通过Cox回归分析发现，患儿接受治疗时年龄越小患牙治疗后失败风险越小，差异有统计学意义(P<0.05)。次氯酸钠溶液结合生理盐水冲洗和是否预成冠修复均对患牙术后失败风险有影响，但差异无统计学意义。结论：遵从目前所使用的诊疗常规，以MTA为盖髓剂的乳磨牙牙髓切断术2年生存率为90.5%，术后失败风险与患儿初诊年龄显著相关，初诊时年龄越大，治疗后失败风险越高。

Objective： To evaluate the two-year outcomes of primary molars pulpotomy using mineral trioxided aggregate (MTA) and to find out the potential influence factor, with the help of electronic medical record database. Methods: Children who received primary molars pulpotomy in the Department of Pediatric Dentistry in Peking University School and Hospital of Stomatology from May, 2014 to November, 2015 were searched in the Electronic Medical Record Database of Peking University School and Hospital of Stomatology, via the database for scientific research provided by the corporation of Kaientai. The children who were healthy, no more than 8 years old and followed up over 1.5 years were selected as the subjects of this study. At the same time, those children who didn’t have complete medical records and X-rays before and after treatment were removed. Basic information, the relevant medical records and radiographic records of those children were collected. All molars were examined clinically and radiographically, and classified into 1 of 5 outcomes: N, H, P0, PX, PY. Molars classified into P0, PX and PY were regarded as failed. Survival analysis was applied. The survival rate and survival time of the deciduous teeth were calculated．Multivariate analysis was performed by using Cox proportional hazard model. Results: One hundred and fifteen children were finally included，aged from 2.6 to 8.2 years, with the mean age of (4.5±1.1) years. 211 primary molars were included, and the average follow up time was (880±154)  days. A good level of agreement between the raters was found for molars with five outcomes(κ=0.913). Intrarater reliability was good for molars with five outcomes (κ=0.916). Forty-nine molars failed by September, 2017. Fortythree molars had abnormal radiographic manifestation. Six molars suffered premature loss. Only fourteen molars had an associated gingival swelling or parulis, or pa-thologic mobility upon clinical examination. The cumulative survival probability of half a year, one year, one year and a half, two years, two year and a half for the pulpotomy was 100%, 98.5%, 92.9%, 90.5%,73.8% through the Kaplan-Meier method, respectively. Through the analysis of Cox proportional hazard model, the survival probability was significantly higher when the age was younger. When sodium hypochlorite and the saline were used as the irrigation at the same time, the survival probability was not improved for those teeth with more bleeding in the operation compared with that used saline only. The teeth with preformed metal crown (PMC) gained longer median survival time than those restored with resin composite and others, but the difference was not significant, either. What’s more, gender, the restoration time of PMC, the restoration of the opposite teeth were not found to be associated with the success of the treatment. Conclusion: The cumulative survival probability of two years after the primary pulpotomy was 90.5%, complying the current instructions in our department. The survival probability of the molars after the treatment was significantly affected by the age.