VOLUME 15 , ISSUE 3 ( March, 2024 ) > List of Articles
Diptiman Shukla, Mohsin A Wani, Thakur P Chaturvedi, Rakesh Koul, Rohit Bahri
Keywords : Anchorage, Cancellous bone, Cortical bone, Finite element analysis, Finite element method, Orthodontic mini-implants, Strain, Stress, Temporary skeletal anchorage devices, von Mises stress
Citation Information : Shukla D, Wani MA, Chaturvedi TP, Koul R, Bahri R. A Three-dimensional Finite Element Study of Stress and Strain Distribution around Orthodontic Mini-implants of Varying Geometry. World J Dent 2024; 15 (3):191-200.
DOI: 10.5005/jp-journals-10015-2394
License: CC BY-NC 4.0
Published Online: 20-04-2024
Copyright Statement: Copyright © 2024; The Author(s).
Aim: The present study aims to generate finite element (FE) models of mini-implants (MIs) inserted in the bone at varying angles, with the purpose of examining the stress and strain distribution patterns within the bone encompassing an MI in response to forces of different magnitudes and applied in different directions. This investigation involves the digitization of the aforementioned models, which will enable a comprehensive analysis of the biomechanical behavior of MIs in bone. Materials and methods: A comprehensive three-dimensional representation of a 35-mm segment of the alveolar bone located in the posterior maxilla, inclusive of a self-drilling titanium MI, was developed. Further models were produced, incorporating diverse lengths, diameters, and implant angulations. The Analysis Software (ANSYS) workbench version 19.1 FE analysis (FEA) program was utilized to calculate the stresses and strains on the MIs with insertion angles of 30 and 60°, diameters of 1.4 and 2 mm, and lengths of 6, 8, 10, and 12 mm. An analysis was conducted to determine the stress distribution at the interface between the implant and bone, using a simulated constant orthodontic force of 2 N, applied in different directions to simulate clinical situations. Results: The stress distribution in cortical and cancellous bone surrounding MIs with dimensions of 1.4 × 6 and 1.4 × 8 mm, inserted at angles of 30 and 60° indicated that the maximum stress value was 61.92 MPa, while the minimum stress value was 20.26 MPa. Furthermore, the stress distribution in cortical bone was significantly higher for the 30° insertion angulation compared to the 60° insertion angulation for MIs with a dimension of 1.4 mm. The minimum stress distribution values obtained for the 30° insertion angulation were 6.61, 6.19, and 2.49 MPa for the three directions of force application calculated. The stress distribution in cancellous bone was minimal, ranging from 0.11 to 0.58 MPa, under altered directions of forces applied during simulated orthodontic tooth movement. Conclusion: The impact of varied insertion angles of orthodontic MIs (OMIs) on stress values and distribution in bone and implant is significant. A 1.4 mm MI generates greater von Mises stress, particularly when inserted at a 30° angle, with strenuous stress at the neck and head of the MI, regardless of its length (6 or 8 mm). Moderate stress levels were observed for cortical bone stresses under horizontal loading for 1.4 mm MIs. Increasing the insertion angle from 30 to 60° resulted in decreased stress concentration around the implant threads. The evaluation of von Mises stress within cancellous bone yielded negligible results due to low-stress transmission. Clinical significance: With the potential to enhance orthodontic treatment through skeletal anchorage, OMIs have gained global acceptance, and since the maintenance of MI permanence is contingent upon its stability, which is significantly impacted by the variables, such as length, diameter, and insertion angle, the utilization of FEA proves to be a more precise and dependable method for the simulation of such meticulous biological and biomechanical conditions.