Finite Element Analysis of Bone around a Dental Implant Supporting a Crown with a Premature Contact
Ekachai Chaichanasiri M Eng*, Pruettha Nanakorn D Eng**, Wichit Tharanon DDS***, Jos Vander Sloten PhD****
Affiliation : * School of Manufacturing Systems and Mechanical Engineering, Sirindhorn International Institute of Technology, Thammasat University, Pathumthani, Thailand ** School of Civil Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, Pathumthani, Thailand *** Advanced Dental Technology Center, National Science and Technology Development Agency, Pathumthani, Thailand **** Division of Biomechanics and Engineering Design, Faculty of Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
Objective : To investigate the influence of a premature contact caused by an implant-retained crown (IRC) on
stress and strain distributions in bone surrounding the implant using the finite element method.
Material and Method: A 3D finite element (FE) model of a section of a mandible with a single tooth dental
implant, an IRC, and two adjacent teeth was created. Three rigid plates were used to represent the antagonist
teeth. Modeling the antagonist teeth using the rigid plates removed the necessity to create FE models for the
antagonist teeth, their periodontal ligament, and the maxilla. Moreover, this new approach also allowed the
premature contact height to be easily varied by changing the positions of the rigid plates. In the present study,
premature contact heights of 0, 50, 100, 150, 200 and 250 μm were considered. The FE contact analysis was
employed. All materials were assumed to be linear elastic and isotropic.
Results : The magnitudes of von Mises stresses in the bone change drastically when there was a premature
contact. For example, the von Mises stress increased from 9.68 MPa in the case with no premature contact to
49.92 MPa in the case with the premature contact height of 50 μm. In addition, the magnitude of the major
principal strain in the marginal bone reached the pathologic overload of 4000 με when the premature contact
height was 100 μm or higher.
Conclusion : The influence of premature contacts is very high and the premature contact height of an IRC over
100 μm should be avoided as much as possible to provide longevity of dental implants.
Keywords : Premature contacts, Finite element method, Dental implants, Teeth, Contact analysis
