Individualization of the three‐piece base arch mechanics according to various periodontal support levels: A finite element analysis

Abstract

Introduction The orthodontic correction of periodontally compromised dentitions constitutes a huge challenge in the clinical practice of adult orthodontics. The biological and physical distinct features of these conditions require a carefully designed mechanical plan for the successful treatment of these complex cases. Setting and Sample Population A segment of a human maxilla containing the central and lateral incisors, obtained from autopsy, was scanned with microcomputed tomography, and a finite element (FE) model was generated to represent an intact periodontal dentition. Based on this model, three additional models simulating a mild, moderate and severe bone alveolar loss were created as well. Materials and Methods Two loading scenarios for the application of intrusive and retraction mechanics with a three‐piece base arch appliance were evaluated in a series of FE analyses. The tooth displacements and strains in the periodontal ligament (PDL) were calculated and compared for the four FE models. Results The periodontal reduced dentitions exhibited a similar axis of resistance for intrusive mechanics, but the axis of resistance for retraction movements was significantly dependent on the degree of alveolar bone loss. The tooth displacements and PDL loads were higher in the reduced dentitions for both intrusive and retraction mechanics. Conclusions A reduction in the force levels applied to periodontal reduced dentitions is indicated, and a customized selection of appropriate points of force application is needed according to the specific amount of alveolar bone loss.

Intrusion of overerupted periodontally compromised posterior teeth using orthodontic mini implants: A mechanobiological finite element study

“…It has been recommended that the orthodontic intrusive force of teeth with reduced alveolar bone support should be decreased proportionally to the periodontal surface loss 6,7,10,19 to maintain PDL stress levels similar to the situation without periodontal compromise (correspondent to the R0 models). However, PDL stresses due to the orthodontic intrusion are not precisely represented by the simplified formula σ = F/A.…”

“…In periodontally compromised teeth intrusion, the risk of root resorption is more critical since the forces applied to a reduced periodontium generate significantly higher stresses and strains within the periodontal ligament (PDL). 6,7 Clinical studies have already shown that patients with reduced but healthy periodontium can undergo orthodontic treatment without aggravating their periodontal conditions. 8,9 Yet, a reduction in the orthodontic force levels is indicated.…”

“…8,9 Yet, a reduction in the orthodontic force levels is indicated. 6,7 Therefore, establishing precise strategies to determine the optimal force magnitude for periodontally compromised teeth has been a goal that permeates contemporary orthodontic practice. 10 The fundamental premise is that the PDL compression should be sufficiently high to promote the desired orthodontic movement in a clinically compatible period and be securely low to avoid root resorption.…”

“…Clinical studies have already shown that patients with reduced but healthy periodontium can undergo orthodontic treatment without aggravating their periodontal conditions 8,9 . Yet, a reduction in the orthodontic force levels is indicated 6,7 …”

Mathematical Modelling and Simulation of Periodontal Ligament Using COMSOL Multiphysics

“…So that it will helps dentists to learn details about the elasticity of periodontal ligament by referring this study. More details about the modelling and simulation of tooth movement can be find in [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17].…”