Implant Design and Stress Distribution

Abstract

Implant design refers to the three-dimensional structure of the implant, with all the elements and characteristics that compose it. Dental implants are subjected to various force magnitudes and directions during function. Because implants function to transfer occlusal loads to the surrounding biologic tissues, functional design objectives should aim to manage biomechanical loads to optimize the implant-supported prosthesis function. Thus, the primary functional design objective is to manage biomechanical loads to optimize the implant-supported prosthesis function. An implant has a macroscopic body design and a microscopic component of implant design. The microscopic features are most important during initial implant healing and the initial loading period. The macroscopic implant body design is most important during early loading and mature loading periods. The product used by the implant team may increase or decrease the risk of screw loosening, crestal bone loss, implant body bone loss, peri-implantitis, esthetics of soft tissue drape, implant failure, and implant body fracture. This article shall help the learner in making a judicious informed decision regarding the different factors governing the reduction of overall stress in implant fixtures and, thus, providing a better treatment to their patients. Search strategy: A literature search was conducted using MEDLINE from 1975 to 2014 to identify studies, from simulated laboratory models, animal, to human, related to this topic using the keywords of implant biomechanics, implant macrodesign, thread pitch, thread geometry, thread depth, thread width, and implant crestal module.

Three-Dimensional Finite Element Investigation into Effects of Implant Thread Design and Loading Rate on Stress Distribution in Dental Implants and Anisotropic Bone

“…In particular, the results have shown that for the buttress and reverse buttress thread models, the application of curved flanks reduces the maximum von Mises stress by up to 50% compared to straight flanks (Table 5), curved flank provides more bone contact area by decreasing the shear stress and tensile stress. Hence, more bone contact area has been proven to offer increased initial stability and stress resistance [87].…”

Three-Dimensional Finite Element Investigation Into Effects of Implant Thread Design and Loading Rate on Stress Distribution in Dental Implants and Anisotropic Bone

“…In particular, the results have shown that for the buttress and reverse buttress thread models, the application of curved flanks reduces the maximum von Mises stress by up to 50% compared to straight flanks (Table 5), curved flank provides more bone contact area by decreasing the shear stress and tensile stress. Hence, more bone contact area has been proven to offer increased initial stability and stress resistance [82].…”

Orthopaedic osseointegration: Implantology and future directions

“…Among different thread shapes available, including v-shaped, square, buttress, reverse-buttress, and spiral-shaped, the square thread profile provides the best primary stability under immediate loading conditions with highest bone implant contact. Both Misch et al 13 and Yadav et al 14 suggested that in dental implants, shear forces in V-thread and reverse buttress threads are 10-fold higher than in a square thread. This reduction in shear loading at the square thread-bone interface induces more compressive load transfer, which is important in conditions where there is compromised bone density.…”