背景：咬合过载被认为是晚期植入物失败的原因之一。然而,目前尚不清楚患者的咬合力大小是否是晚期植入失败的危险因素.
目的：本病例对照研究旨在阐明咬肌横截面积（CSA）与晚期植入物失败之间的关联。
方法：本病例对照研究仅限于植入物支持的固定假体。我们将至少有一次晚期植入物失败的病例（n=25例）与没有植入物失败的对照组（n=82例）进行了比较。患者按年龄匹配，性别,手术年份,颌骨和牙齿类型，和植骨。使用Log-rank和Cox比例风险回归分析来确定晚期植入物失败的可能风险因素。
结果：晚期植入物失败的发生率与咬肌CSA≥504.5mm2显着相关（风险比：4.43；95％CI：1.82-10.79；p<0.01）。
结论：较高的咬肌CSA会增加晚期植入失败的风险。
BACKGROUND: Occlusal overload is considered to be one of the causes of late implant failure. However, it is unclear whether the magnitude of the patient\'s occlusal force is a risk factor for late implant failure.
OBJECTIVE: This
case-control study aimed to clarify the association between the cross-sectional area (CSA) of the masseter muscle and late implant failure.
METHODS: This
case-control study was limited to implant-supported fixed prostheses. We compared cases with at least one late implant failure (n = 25 patients) to controls (n = 82 patients) without implant failure. Patients were matched by age, sex, year of surgery, jaw and tooth type, and bone graft. Log-rank and Cox proportional hazard regression analyses were used to identify possible risk factors for late implant failure.
RESULTS: The incidence of late implant failure was significantly associated with masseter muscle CSA ≥504.5 mm2 (hazard ratio: 4.43; 95% CI: 1.82-10.79; p < 0.01).
CONCLUSIONS: Higher masseter muscle CSA increases the risk of late implant failure.
