Int J Oral Maxillofac Implants. 2019 November/December;34(6):1434–1440. doi: 10.11607/jomi.7565. Epub 2019 Sep 18.
To treat mandibular edentulous patients by fitting immediately loaded two-implant overdentures via guided flapless surgery and evaluate their masticatory performance.
Nineteen patients who presented with edentulous mandibles (mean age: 69.8 years; range: 60 to 85 years) at the Dental Hospital, Tokyo Medical and Dental University, were enrolled in this study. A newly fabricated complete denture was used as a radiographic guide. Computer planning followed the design procedure, and surgical guides were fabricated for each patient. Flapless surgery was performed using this guide, and two implants were placed in the canine positions. On the day of surgery, a removable overdenture supported by two ball attachments was fitted. Masticatory function was evaluated on the basis of masticatory performance with a color-changeable chewing gum, maximum occlusal force with an occlusal force meter, and occlusal contact area with an occlusal diagnostic system.
The masticatory performance significantly improved from 48 months after surgery. The maximum occlusal force significantly increased 24 months after surgery. The occlusal contact area significantly increased from 6 months after surgery. This prospective study indicated that maximum occlusal force and occlusal contact area significantly improved at a comparatively earlier period after implant surgery and were maintained for up to 5 years with the immediate loading of two-implant overdentures with stud attachments. However, masticatory performance took more time to improve than maximum occlusal force and occlusal contact area.
According to this 5-year prospective study, masticatory performance, maximum occlusal force, and occlusal contact area showed significant improvement after 4 to 5 years, 2 years, and 6 months postsurgery, espectively.
通过无瓣引导式手术即刻负载两种植体覆盖义齿来治疗下颌无牙颌患者，并评估其咀嚼性能。
本研究纳入了东京医科齿科大学牙科医院 19 名下颌无牙颌患者（平均年龄：69.8 岁；范围：60 至 85 岁）。使用新制作的全口义齿作为放射影像引导。计算机设计遵循设计流程，为每位患者制作了手术导板。使用该导板进行无瓣手术，并在前磨牙位置植入两颗种植体。手术当天，为患者佩戴由两个球附着体支撑的可摘式覆盖义齿。通过变色咀嚼胶评估咀嚼功能、使用咬合测力仪评估最大咬合力量、使用咬合诊断系统评估咬合接触面积来评估咀嚼功能。
术后 48 个月咀嚼功能显著改善。术后 24 个月最大咬合力量显著增加。术后 6 个月咬合接触面积显著增加。这项前瞻性研究表明，种植体即刻负载覆盖义齿（带栓体附着体）在术后较短时间内即可显著提高最大咬合力量和咬合接触面积，并可维持 5 年。然而，咀嚼功能的改善需要比最大咬合力量和咬合接触面积更长的时间。
根据这项为期 5 年的前瞻性研究，术后 4 至 5 年、2 年和 6 个月时，咀嚼性能、最大咬合力量和咬合接触面积分别显著改善。
