Three-dimensional finite element analysis of extra short implants focusing on implant designs and materials

Abstract

Aim: When using short implants, fracture of the implant body and bone resorption are a concern because stress concentrates on and around a short implant. The purpose of this research is to investigate the differences in stress distribution between tissue level (TL) and bone level (BL) implant body designs, and between commercially pure titanium (cpTi) and the newer titanium-zirconium (TiZr) alloy in using short implants. Materials and methods: Models of TL and BL implants were prepared for three-dimensional finite element analysis. The implants were produced in 10 mm, 8 mm, and 6 mm lengths, and the TL was also produced in a 4-mm length. A static load of 100 N inclined at 30°to the long axis was applied to the buccal side of the model. The largest maximum principal stress value in the cortical bone and the largest von Mises stress value in the implant body were evaluated. Results: Stress concentration was observed at the connection part of the implant, especially above the bone in TL and within the bone in BL. In the TL design, tensile stress occurred on the buccal side and compressive stress on the lingual side of the cortical bone. Conversely, in the BL design, tensile stress occurred on the lingual side of the cortical bone. CpTi and TiZr showed a similar stress distribution pattern. The maximum stress values were lower in the TL design than the BL design, and they were lower with TiZr than cpTi for both the cortical bone and implant body. The maximum value tended to increase as the length of the implant body decreased. In addition, the implant body design was more influential than its length, with the TL design showing a stress value similar to the longer BL design. Conclusion: Using TiZr and a TL design may be more useful mechanically than cpTi and a BL design when the length of the implant body must be shorter because of insufficient vertical bone mass in the mandible.

Effect of Different Implant Designs on Strain and Stress Distribution under Non-Axial Loading: A Three-Dimensional Finite Element Analysis

“…A similar situation was found in the research of Araki et al [ 34 ], with a greater stress concentration on the cortical bone around the neck of the implants, although this study was performed with shorter dental implants than those used in the present work. Herekar et al [ 35 ] and Baggy et al [ 36 ] also observed higher von Mises stress values located at cervical cortical bone regions adjacent to the implants for different implant types.…”

“…Contrary to the present work, Araki et al [ 34 ] reported a higher von Mises stress distribution in bone for bone-level and tissue-level implants; however, they used other implant types and focused on extra short implants in their study.…”

Comparison of CAD/CAM manufactured implant-supported crowns with different analyses

“…The finite element analysis (FEA) has been widely used in implant dentistry to evaluate the effect of both biomechanical and clinical factors on implant success. This analysis identifies stresses and displacements on the prosthesis-implant-bone complex which can be unachievable for other biomechanical methods [41][42][43]. Therefore, in this study, FEA was used to compare the stress distribution of different glass ceramics and the effect of veneering on the prosthesis-implant-bone complex.…”

The Trends of TiZr Alloy Research as a Viable Alternative for Ti and Ti16 Zr Roxolid Dental Implants

“…Young's Modulus (GPa) A series of TiZr alloys were compared with cp-Ti. The TixZr alloys with Zr content ranging from 5% to 85% were characterized [22][23][24] in terms of stress distribution, surface topography at the micro-level, electrochemical stability in a simulated oral cavity environment, in vitro cell cultures, and pre-clinical and clinical studies. Fracture of the implant body and bone resorption caused by stress around implants were investigated by finite element method, and clinical investigations concluded that the narrow-diameter TiZr implants present similar success rates and peri-implant bone resorption as cp-Ti implants of comparable dimensions [24].…”