Harinakano Family Dentistry, Osaka, Japan.
Department of Prosthodontics, Gerodontology and Oral Rehabilitation, Osaka University Graduate School of Dentistry, Osaka, Japan.
J Prosthodont Res. 2021 Oct 15;65(4):541-545. doi: 10.2186/jpr.JPR_D_20_00077. Epub 2021 Apr 23.
Purpose This study aimed to determine the influence of mandibular free-end partial edentulism and use of conventional or implant-supported removable dental prostheses in the partially edentulous area on the load exerted on the maxillary anterior teeth.Methods A jaw model with mandibular free-end missing teeth was used, and a distal extension, removable partial dental prosthesis was fabricated to replace the missing posterior teeth. Four experimental conditions were set up: 1) without prosthesis, 2) with a conventional removable partial dental prosthesis, 3) with an implant-supported removable partial dental prosthesis, and 4) with a complete dental arch. Strain gauges were attached to the root surface of the maxillary left central incisor, canine, first premolar, and first molar. The load exerted on them was calculated based on the calibration coefficient. An occlusal load of 49 N was applied, and the forces were compared using a Kruskal-Wallis test (P < 0.05). Results The load exerted on the maxillary anterior teeth increased significantly with no prosthesis, decreased significantly with a conventional removable partial dental prosthesis, and decreased even more significantly with an implant-supported removable partial dental prosthesis. Conclusions The burden on the maxillary anterior teeth decreased with the use of a removable partial dental prosthesis and decreased even further with the use of an implant-supported dental prosthesis. The use of an implant to support a distal extension removable partial dental prosthesis is potentially effective in preserving the remaining teeth and tissues by reducing excessive stress in patients with mandibular free-end partial edentulism.
目的 本研究旨在确定下颌游离端部分牙列缺失以及在部分缺牙区使用传统或种植体支持可摘义齿对上颌前牙所受负荷的影响。
方法 采用下颌缺失牙的颌模型,制作远中游离端可摘局部义齿以替代缺失的后牙。共设置 4 种实验条件:1)无义齿,2)传统可摘局部义齿,3)种植体支持的可摘局部义齿,4)全牙弓。在左侧上颌中切牙、尖牙、第一前磨牙和第一磨牙的根表面粘贴应变片,根据校准系数计算其受力。施加 49 N 的咬合负荷,采用 Kruskal-Wallis 检验(P<0.05)比较各力。
结果 无义齿时上颌前牙受力明显增加,使用传统可摘局部义齿时显著减少,使用种植体支持的可摘局部义齿时进一步显著减少。
结论 可摘局部义齿的使用减轻了上颌前牙的负担,种植体支持的可摘局部义齿的使用进一步减轻了负担。对于下颌游离端部分牙列缺失的患者,使用种植体支持远中游离端可摘局部义齿可通过减少过度的应力,从而有效地保护剩余牙齿和组织。