Clinical Professor, Department of Prosthodontics, Seoul National University Dental Hospital, Seoul, Republic of Korea.
Professor, Department of Prosthodontics & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
J Prosthet Dent. 2023 May;129(5):732-740. doi: 10.1016/j.prosdent.2021.06.053. Epub 2021 Sep 1.
Internal conical connections have become the primary choice for implant-supported restorations. However, studies that identified the risk indicators for mechanical complications and diagnosed the prognosis of the implant-supported restorations are lacking.
The purpose of this retrospective clinical study was to evaluate the incidence and consequences of mechanical complications in components of internal conical connection implants and to analyze the risk indicators.
A total of 428 patients with 898 internal conical connection implants were included in the study, and mechanical complications over the 14-year observation period were evaluated. The Cox proportional hazard regression model was used to analyze significant effects on mechanical complications, which were presented as hazard ratio and 95% confidence interval.
Mechanical complications occurred in 430 (47.9%) implants and 248 (57.9%) patients: screw loosening (46.4% of implants, 56.8% of patients); screw fracture (2.6% of implants, 4.4% of patients); abutment fracture (11.4% of implants, 21.3% of patients); and implant fracture (3.5% of implants, 5.4% of patients). Implant restorations replacing molars showed the highest risk for mechanical complication (hazard ratio 12.82; 95% confidence interval 2.73-60.31) and for fracture of all components. Men had a higher risk of mechanical complication than women (hazard ratio 2.00; 95% confidence interval 1.55-2.59), and the risk of fracture was higher in all components. With increased splinted implants, the risk of mechanical complication (hazard ratio 0.67; 95% confidence interval 0.49-0.93) and component fracture (hazard ratio 0.73; 95% confidence interval 0.29-0.89) decreased. Gold screws had a lower risk of screw loosening (hazard ratio 0.74; 95% confidence interval 0.58-0.94) than titanium screws, but a higher risk of fracture (hazard ratio 3.45; 95% confidence interval 1.42-8.36). The smaller the implant diameter, the higher the risk of implant fracture (hazard ratio 0.01; 95% confidence interval 0.00-0.05).
Abutments were most frequently fractured among the components of internal conical connection type implants. Molar implant-supported restorations and male patients had higher risks of mechanical complications, and as the number of splinted implants in a prosthesis increased, the risk decreased. Gold screws showed less risk of screw loosening and higher risk of fracture than titanium screws. Narrow-diameter implants had a higher risk of fracture.
内部锥形连接已成为种植体支持修复的首选。然而，缺乏确定机械并发症风险指标并诊断种植体支持修复预后的研究。
本回顾性临床研究旨在评估内部锥形连接种植体部件中机械并发症的发生率和后果，并分析风险指标。
共纳入 428 名患者的 898 个内部锥形连接种植体，在 14 年的观察期内评估机械并发症。使用 Cox 比例风险回归模型分析对机械并发症有显著影响的因素，结果以风险比和 95%置信区间表示。
430 个（47.9%）种植体和 248 名（57.9%）患者发生机械并发症：螺丝松动（46.4%的种植体，56.8%的患者）；螺丝断裂（2.6%的种植体，4.4%的患者）；基台折断（11.4%的种植体，21.3%的患者）；种植体折断（3.5%的种植体，5.4%的患者）。修复磨牙的种植体修复体发生机械并发症的风险最高（风险比 12.82；95%置信区间 2.73-60.31）和所有部件折断的风险也最高。男性发生机械并发症的风险高于女性（风险比 2.00；95%置信区间 1.55-2.59），所有部件折断的风险也更高。随着夹板种植体数量的增加，机械并发症（风险比 0.67；95%置信区间 0.49-0.93）和部件折断（风险比 0.73；95%置信区间 0.29-0.89）的风险降低。金螺丝的螺丝松动风险低于钛螺丝（风险比 0.74；95%置信区间 0.58-0.94），但折断风险较高（风险比 3.45；95%置信区间 1.42-8.36）。种植体直径越小，种植体折断的风险越高（风险比 0.01；95%置信区间 0.00-0.05）。
在内部锥形连接类型种植体的部件中，基台最常折断。磨牙种植体支持修复和男性患者发生机械并发症的风险较高，随着修复体中夹板种植体数量的增加，风险降低。金螺丝的螺丝松动风险低于钛螺丝，但折断风险较高。窄直径种植体折断风险较高。
