Department of Oral Rehabilitation, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
J Appl Oral Sci. 2011 Nov-Dec;19(6):655-61. doi: 10.1590/s1678-77572011000600019.
In some clinical situations, dentists come across partially edentulous patients, and it might be necessary to connect teeth to implants. The aim of this study was to evaluate a metal-ceramic fixed tooth/implant-supported denture with a straight segment, located in the posterior region of the maxilla, when varying the number of teeth used as abutments.
A three-element fixed denture composed of one tooth and one implant (Model 1), and a four-element fixed denture composed of two teeth and one implant (Model 2) were modeled. A 100 N load was applied, distributed uniformly on the entire set, simulating functional mastication, for further analysis of the SEQV (Von Mises) principal stresses, which were compared with the flow limit of the materials.
In a quantitative analysis, it may be observed that in the denture with one tooth, the maximum SEQV stress was 47.84 MPa, whereas for the denture with two teeth the maximum SEQV stress was 35.82 MPa, both located in the region between the pontic and the tooth.
Lower stresses were observed in the denture with an additional tooth. Based on the flow limit of the materials, porcelain showed values below the limit of functional mastication.
在某些临床情况下,牙医会遇到部分无牙患者,可能需要将牙齿连接到种植体上。本研究旨在评估在上颌后区带有直段的金属-陶瓷固定牙/种植体支持义齿,当使用的基牙数量发生变化时。
模拟了由一个牙和一个种植体组成的三单位固定义齿(模型 1)和由两个牙和一个种植体组成的四单位固定义齿(模型 2)。施加 100 N 的负载,均匀分布在整个集合上,模拟功能咀嚼,进一步分析 SEQV(冯·米塞斯)主应力,与材料的流动极限进行比较。
在定量分析中,可以观察到在一个牙的义齿中,最大 SEQV 应力为 47.84 MPa,而在两个牙的义齿中,最大 SEQV 应力为 35.82 MPa,两者都位于桥体和牙齿之间的区域。
在有额外牙齿的义齿中观察到较低的应力。基于材料的流动极限,瓷显示的值低于功能咀嚼的极限。