锥度固位结合数字化技术在后牙连续多牙种植即刻修复中的应用

目的:评价口内扫描技术、计算机辅助设计/加工(computer-assisted design/computer-assisted manufacturing, CAD/CAM)技术结合锥度固位方式在种植即刻修复连续多牙缺失中的应用。方法: 选取2017年3月至2018年2月于北京大学口腔医院种植科就诊的连续多个后牙缺失的患者,在种植体植入即刻安放预成锥度固位帽,通过口内扫描制取数字化印模,以CAD/CAM技术制作聚甲基丙烯酸甲酯 (polymethyl methacrylate, PMMA) 临时联冠,临时联冠戴入后即刻负重;6个月后更换为CAD/CAM技术制作的氧化锆永久联冠,临时冠及永久冠戴入时分别拍摄平行投照牙片。通过种植体和修复体存留率、种植体颈部边缘骨水平变化、种植体和修复体并发症等指标评价临床效果,永久修复前用视觉模拟评分 (visual analogue score, VAS) 量表评价患者对即刻修复的满意度。结果:共计10例患者(男4例,女6例,平均55.5岁)纳入本研究,共植入34枚种植体,分别制作14件即刻PMMA修复体和14件永久氧化锆修复体,观察时间4~14个月;种植体及修复体存留率100%,种植体颈部骨水平在种植即刻为(1.06±0.97) mm,即刻修复后6个月时为(0.96±0.82) mm,两者差异无统计学意义(P>0.05);观察期内所有种植体和修复体均未发生并发症;患者满意度VAS评分87.2。结论:对于连续多牙缺失,在种植即刻以数字化流程制作,并结合锥度固位方式的联冠修复体,具有良好的临床效果和患者满意度。

Digital workflow coupling conic retention for the immediate restoration of adjacent posterior implants

Objective: To evaluate the digital workflow coupling conic retention for the immediate restoration of adjacent posterior implants. Methods: The patients with adjacent teeth missing in the posterior jaw seeking for implant restoration in the Department of Implantology, Peking University School and Hospital of Stomatology from March, 2017 to February, 2018 were recruited. After implant placement and commercial conic retention coping delivery, the patient had an intraoral scan for digital impression, and the computer-assisted design/computer-assisted manufacturing (CAD/CAM) technology was used for the fabrication of the immediate splinted prosthesis, which was made of polymethyl methacrylate (PMMA) and loaded immediately after delivery. Six months later, all the temporary prostheses were replaced by the permanent ones made of monolithic zirconia with CAD/CAM technology as well. The parallel periapical films were taken for the temporary and permanent prostheses post-delivery. The clinical effect of this workflow was evaluated by indices including the survival rates of implants and prostheses, the change of marginal bone level, and the implant-related and prosthesis-related complications; before the final restoration, the Visual Analogue Score (VAS) was used to evaluate the satisfaction of the patients. Results: Ten patients (4 males and 6 females, 55.5 years old for average) were recruited. Totally 34 implants were placed; 14 prostheses were fabricated, temporary and permanent, respectively. After an observation period from 4 to 14 months, the survival rate for implants and prostheses were both 100%; the marginal bone level of the implants were (1.06±0.97) mm and (0.96±0.82) mm, immediate post-operation and 6 months later, respectively. The difference was not statistically significant (P>0.05). Neither implant- nor prostheses- related complications were observed. And the VAS of the patients' satisfaction was 87.2. Conclusion: For the adjacent posterior implants, the immediate prostheses manufactured by digital workflow, coupling conic retention, were clinically feasible and patient-satisfactory.