Abstract：
OBJECTIVE: To investigate the timing of implant failure events and their relationship with the dental position and the factors affecting the survival time of implants.
METHODS: A retrospective cohort study was conducted to analyze the patients who had implants removed due to implant failure in the Department of Dental Implantology of Hefei Stomatological Hospital from January 2019 to December 2021. The predictor variables were surgical age, gender, smoking habit, oral hygiene, glucose value, jaw and dental position, implant type, implant number, surgeon, implant placement timing, implant loading timing, and antibiotic use timing. The outcome measurement was the implant survival time and implant failure events. Chi-square test, Kaplan-Meier(Log-rank test), and Cox proportional hazards model were used to identify and stepwise determined potential risk factors for implant survival time with SPSS 21.0 software package.
RESULTS: A total of 89 patients(95 implants) had to remove implants. The mean survival time of the failed implants was 31(95%CI :24.2-39.1) months. Implant number (P=0.038), implant loading timing (P=0.050), and tooth position (P=0.024) were significantly correlated with the implant survival time. The risk of failure with 2 implants was 2.709 (HR=3.709, 95%CI: 1.075-12.795) times higher than that with 1 implant, and the risk of failure with late implant loading was 0.551(HR=1.511, 95%CI: 0.999-2.406) times higher than that with early implant loading. The risk of anterior teeth implant failure was 1.384 times higher than that of molars(HR=2.384, 95%CI:1.327-4.283). For patients with implant failure, about 50% of the patients removed the failed implant within 1 year after surgery, and the rate of removal of the failed implant gradually slowed down in the following 2-10 years. Peri-implantitis most commonly occurred in molars(50%). Implant fracture lastly occurred at 55(95%CI: 42.2-67.9) months postoperatively（P=0.000）.
CONCLUSIONS: The number of implants, implant loading timing, and dental position were considered as the influencing factors for the survival time of implants. Follow-up in the first year after implantation seems to be particularly important for timely detection of problems and timely intervention. The occurrence of implant failure events was related to dental position and time.
METHODS: A retrospective cohort study was conducted to analyze the patients who had implants removed due to implant failure in the Department of Dental Implantology of Hefei Stomatological Hospital from January 2019 to December 2021. The predictor variables were surgical age, gender, smoking habit, oral hygiene, glucose value, jaw and dental position, implant type, implant number, surgeon, implant placement timing, implant loading timing, and antibiotic use timing. The outcome measurement was the implant survival time and implant failure events. Chi-square test, Kaplan-Meier(Log-rank test), and Cox proportional hazards model were used to identify and stepwise determined potential risk factors for implant survival time with SPSS 21.0 software package.
RESULTS: A total of 89 patients(95 implants) had to remove implants. The mean survival time of the failed implants was 31(95%CI :24.2-39.1) months. Implant number (P=0.038), implant loading timing (P=0.050), and tooth position (P=0.024) were significantly correlated with the implant survival time. The risk of failure with 2 implants was 2.709 (HR=3.709, 95%CI: 1.075-12.795) times higher than that with 1 implant, and the risk of failure with late implant loading was 0.551(HR=1.511, 95%CI: 0.999-2.406) times higher than that with early implant loading. The risk of anterior teeth implant failure was 1.384 times higher than that of molars(HR=2.384, 95%CI:1.327-4.283). For patients with implant failure, about 50% of the patients removed the failed implant within 1 year after surgery, and the rate of removal of the failed implant gradually slowed down in the following 2-10 years. Peri-implantitis most commonly occurred in molars(50%). Implant fracture lastly occurred at 55(95%CI: 42.2-67.9) months postoperatively（P=0.000）.
CONCLUSIONS: The number of implants, implant loading timing, and dental position were considered as the influencing factors for the survival time of implants. Follow-up in the first year after implantation seems to be particularly important for timely detection of problems and timely intervention. The occurrence of implant failure events was related to dental position and time.
摘要：
目的：探讨种植体失效事件发生的时间及其与牙位的关系以及影响种植体存活时间的因素。
方法：采用回顾性队列研究方法，对2019年1月至2021年12月合肥市口腔医院口腔种植内科因种植失败而摘除种植体的患者进行分析。预测变量为手术年龄，性别,吸烟习惯,口腔卫生,葡萄糖值，下巴和牙齿的位置，植入物类型,植入物编号,外科医生,植入物放置时机,植入物加载时间,和抗生素使用时机。结果测量为植入物存活时间和植入物失败事件。卡方检验,卡普兰-迈耶(对数秩检验)，和Cox比例风险模型用于识别和逐步确定植入物生存时间的潜在危险因素，并使用SPSS21.0软件包。
结果：共有89名患者（95个植入物）需要移除植入物。失败植入物的平均生存时间为31（95CI：24.2-39.1）个月。种植体数(P=0.038),植入物加载时间（P=0.050），牙位(P=0.024)与种植体存活时间显著相关。使用2个植入物失败的风险是使用1个植入物的2.709（HR=3.709，95CI：1.075-12.795）倍，晚期植入物负荷失败的风险比早期植入物负荷高0.551倍(HR=1.511,95CI:0.999-2.406).前牙种植失败的风险是磨牙的1.384倍（HR=2.384，95CI：1.327-4.283）。对于植入失败的患者，大约50％的患者在手术后1年内切除了失败的植入物，在接下来的2-10年内，失败的植入物的去除速度逐渐减慢。种植体周围炎最常见于磨牙（50％）。种植体骨折最多发生于术后55(95CI:42.2～67.9)个月（P=0.000）。
结论：植入物的数量，植入物加载时间,牙位是种植体存活时间的影响因素。植入后第一年的随访对于及时发现问题和及时干预显得尤为重要。种植失败事件的发生与牙齿位置和时间有关。
方法：采用回顾性队列研究方法，对2019年1月至2021年12月合肥市口腔医院口腔种植内科因种植失败而摘除种植体的患者进行分析。预测变量为手术年龄，性别,吸烟习惯,口腔卫生,葡萄糖值，下巴和牙齿的位置，植入物类型,植入物编号,外科医生,植入物放置时机,植入物加载时间,和抗生素使用时机。结果测量为植入物存活时间和植入物失败事件。卡方检验,卡普兰-迈耶(对数秩检验)，和Cox比例风险模型用于识别和逐步确定植入物生存时间的潜在危险因素，并使用SPSS21.0软件包。
结果：共有89名患者（95个植入物）需要移除植入物。失败植入物的平均生存时间为31（95CI：24.2-39.1）个月。种植体数(P=0.038),植入物加载时间（P=0.050），牙位(P=0.024)与种植体存活时间显著相关。使用2个植入物失败的风险是使用1个植入物的2.709（HR=3.709，95CI：1.075-12.795）倍，晚期植入物负荷失败的风险比早期植入物负荷高0.551倍(HR=1.511,95CI:0.999-2.406).前牙种植失败的风险是磨牙的1.384倍（HR=2.384，95CI：1.327-4.283）。对于植入失败的患者，大约50％的患者在手术后1年内切除了失败的植入物，在接下来的2-10年内，失败的植入物的去除速度逐渐减慢。种植体周围炎最常见于磨牙（50％）。种植体骨折最多发生于术后55(95CI:42.2～67.9)个月（P=0.000）。
结论：植入物的数量，植入物加载时间,牙位是种植体存活时间的影响因素。植入后第一年的随访对于及时发现问题和及时干预显得尤为重要。种植失败事件的发生与牙齿位置和时间有关。
