Chitumalla Rajkiran, Munaga Swapna, Khare Amit, Agarwal Surendra, Bhoyar Anjali, Parlani Swapnil
Department of Prosthodontics, Crown and Bridge and Implantology, People's College of Dental Sciences and Research Centre, Karond, Bhanpur, Bhopal, Madhya Pradesh, India.
Contemp Clin Dent. 2012 Oct;3(4):452-8. doi: 10.4103/0976-237X.107439.
The aim of the study was to evaluate the stress distribution patterns in teeth and supporting structures of fixed prosthesis and design modifications in a fixed prosthesis with either normal or reduced bone support of an additional abutment. Study was also undertaken to disprove Ante's law.
Main models and variations of main models (modification 1, 2, 3, 4, 5, 6, 7, 8) were subjected to 200 N at angulations of 90° and 15° on functional cusps. Results for each loading were obtained as stress distribution color images and numerical values were recorded. A three-dimensional finite element analysis study of variations of normal models was performed using two finite element softwares, namely PRO-Engineer wildfire version 1.0 manufacturer: Parametric technology corporation, Needham, MA 02494 U.S.A.
When periodontal compromised abutment teeth was splinted with an additional abutment an increase of stress was observed in periodontally compromised abutments so an additional abutment is not required. Eventhough the pericemental area of compromised abutments with an additional abutment (canine) was more than the combined pericemental area of pontics to be replaced, stress generated was more on abutments. This disproves Ante's law. Hence, it may be a reference, but should not be the ultimate criterion in determining the number of multiple abutments.
When periodontal compromised abutment teeth was splinted with an additional abutment an increase of stress was observed in periodontally compromised abutments so an additional abutment is not required. Even though the pericemental area of compromised abutments with an additional abutment (canine) was more than combined pericemental area of pontics to be replaced, stress generated was more on abutments. This disproves Ante's law. Hence, it may be a reference, but should not be the ultimate criterion in determining the number of multiple abutments.
本研究的目的是评估固定义齿的牙齿及支持结构中的应力分布模式,以及在具有正常或减少骨支持的额外基牙的固定义齿中的设计修改。还进行了研究以反驳安特法则。
主要模型及其变体(修改1、2、3、4、5、6、7、8)在功能尖处以90°和15°的角度承受200 N的力。每次加载的结果以应力分布彩色图像形式获得,并记录数值。使用两种有限元软件对正常模型的变体进行三维有限元分析研究,这两种软件分别是PRO-Engineer野火版1.0(制造商:参数技术公司,美国马萨诸塞州尼德姆02494)。
当牙周受损的基牙用额外基牙进行夹板固定时,观察到牙周受损基牙中的应力增加,因此不需要额外基牙。尽管带有额外基牙(尖牙)的受损基牙的牙周膜面积大于要替换的桥体的联合牙周膜面积,但基牙上产生的应力更大。这反驳了安特法则。因此,它可能是一个参考,但不应是确定多个基牙数量的最终标准。
当牙周受损的基牙用额外基牙进行夹板固定时,观察到牙周受损基牙中的应力增加,因此不需要额外基牙。尽管带有额外基牙(尖牙)的受损基牙的牙周膜面积大于要替换桥体的联合牙周膜面积,但基牙上产生的应力更大。这反驳了安特法则。因此,它可能是一个参考,但不应是确定多个基牙数量的最终标准。