Comparing the influence of crestal cortical bone and sinus floor cortical bone in posterior maxilla bi-cortical dental implantation: A three-dimensional finite element analysis

Abstract

Objective. This study aimed to compare the influence of alveolar ridge cortical bone and sinus floor cortical bone in sinus areabi-cortical dental implantation by means of 3D finite element analysis. Materials and methods. Three-dimensional finite element (FE) models in a posterior maxillary region with sinus membrane and the same height of alveolar ridge of 10 mm were generated according to the anatomical data of the sinus area. They were either with fixed thickness of crestal cortical bone and variable thickness of sinus floor cortical bone or vice versa. Ten models were assumed to be under immediate loading or conventional loading. The standard implant model based on the Nobel Biocare implant system was created via computer-aided design software. All materials were assumed to be isotropic and linearly elastic. An inclined force of 129 N was applied. Results. Von Mises stress mainly concentrated on the surface of crestal cortical bone around the implant neck. For all the models, both the axial and buccolingual resonance frequencies of conventional loading were higher than those of immediate loading; however, the difference is less than 5%. Conclusion. The results showed that bi-cortical implant in sinus area increased the stability of the implant, especially for immediately loading implantation. The thickness of both crestal cortical bone and sinus floor cortical bone influenced implant micromotion and stress distribution; however, crestal cortical bone may be more important than sinus floor cortical bone.

Key Words:

• finite element analysis
• bi-cortical implant
• stress distribution
• resonance frequencies
• sinus floor

Acknowledgment

This research was supported by the National High Technology Research and Development Program of China (863 Program, 2011AA030107) and Young Scholars foundation, School of Stomatology, China Medical University, Shenyang, China (grants K101593-12-34). The authors would like to thank the Regenerative Dentistry and Implant Center and Section of Removable Prosthodontics, Division of Oral Rehabilitation, the Faculty of Dental Science, Kyushu University, Fukuoka, Japan, for their support and allowing us to use their facilities.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.