[Three-dimensional finite element analyses of bone surface stress of two kinds of conjunction implant].

Objective: To establish a three-dimension finite element model of mandible with two kinds of dental implant and to study the stress of implant-bone interface.

Methods: Measuring the data of the components of the dental implant and using spiral CT image reconstruction technique to scan the cross section of the mandible. Three-dimension finite element analysis software Unigraphics and MSC. Marc/Mentat were used to build the conjunction model and bone model of two implant systems. Loading 200 N axially and 100 N 30 degrees obliquely on the models respectively, the stress distribution patterns of the bone interface of two implant systems were analyzed.

Results: The stress distribution on the bone interface of two implant systems was similar. The peak stress of oblique loading was higher than that of axial loading. The peak stress district of the bone was concentrated on the stricture of the implant cervix, which was more obviously displayed on the Replace Select implant. The peak stresses on the bone interface of Replace Select implant were higher than that of Replace implant in all loadings.

Conclusion: To Replace Select especially, oblique force should be avoided in clinical practice in case of the bone absorption.