Inclusion of periodontal ligament fibres in mandibular finite element models leads to an increase in alveolar bone strains

The objective of the present study is to describe the stress and displacement patterns created by clear aligners and composite attachments bonded with the acid-etch technique on the labial surface of the maxillary first upper molar during its distalization. Maxillary molar distalization is a clinical orthodontics procedure used to move the first maxillary molar distally. The procedure is useful in patients with some Class II malocclusion allowing the first molar to move into a Class I relationship and the correction of associated malocclusion features. Three finite element models were designed to simulate the alveolar bone, molar tooth, periodontal ligament, aligner, and composite attachments. The first model had no composite attachment, the second model had a vertical rectangular attachment, and the third model had a newly designed attachment. A loading method was developed that mimicked the aligner’s molar distal movement. PDL was set as a viscoelastic material with a nonlinear mechanical response. von Mises and maximum principal stresses and tooth displacement patterns were analyzed using dedicated software. All the configurations showed some form of clockwise rotation in addition to the distal movement. The crown portion of the tooth showed maximum displacement in all three models; however, in the absence of attachment, the root apex moved in the opposite direction which was compatible with uncontrolled tipping movement. Simulations with attachments exhibited the best performance regarding the movement patterns. The third group, with the newly designed attachment, exhibited the best performance concerning stress distribution (principal stress and von Mises stresses) and higher stresses in the periodontal ligament and tooth. Incorporating a vertical rectangular attachment in a clear aligner resulted in the reduction of mesiodistal tipping tendency during molar distalization. The third model was the most efficient considering both displacement pattern and stress distribution. The level of stress generated by the third model needs to be further investigated in future studies.

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Use of 3D finite element models in study of normal and abnormal dental mobility as affected by a minimal decrease in alveolar bone height

Journal of Physics Conference Series ◽

10.1088/1742-6596/1129/1/012028 ◽

2018 ◽

Vol 1129 ◽

pp. 012028

Author(s):

S E Peshin ◽

E P Rogozhnikova ◽

O I Dudar ◽

N B Astashina

Keyword(s):

Finite Element ◽

Alveolar Bone ◽

Finite Element Models ◽

3D Finite Element ◽

Bone Height

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An investigation into the importance of the periodontal ligament and alveolar bone as supporting structures in finite element studies

Journal of Oral Rehabilitation ◽

10.1046/j.1365-2842.2001.00686.x ◽

2001 ◽

Vol 28 (5) ◽

pp. 425-432 ◽

Cited By ~ 64

Author(s):

J. S. Rees

Keyword(s):

Finite Element ◽

Periodontal Ligament ◽

Alveolar Bone ◽

Supporting Structures

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Analysis of Stress in the Periodontal Ligament and Alveolar Bone of the Maxillary First Molars during Intrusion with Microscrew Implants: A 3D Finite Element Study

World Journal of Dentistry ◽

10.5005/jp-journals-10015-1250 ◽

2014 ◽

Vol 5 (1) ◽

pp. 11-16 ◽

Cited By ~ 1

Author(s):

AS Pavithra ◽

GS Prashanth ◽

SE Shekar

Keyword(s):

Finite Element ◽

Periodontal Ligament ◽

Maximum Stress ◽

Alveolar Bone ◽

Root Surface ◽

3D Finite Element ◽

Finite Element Study ◽

Palatal Implant ◽

Transpalatal Arch ◽

Element Study

ABSTRACT Objectives The objective of this study was to graphically display the pattern and magnitude of stress distribution along the periodontal ligament and the alveolar bone of upper first molars on application of intrusive forces using microscrew implants. Materials and methods A computer simulation of threedimensional model of maxillary first molars and second molars bilaterally with their periodontal ligament and alveolar bone, with microscrew implants, force element and a transpalatal arch were constructed on the basis of average anatomic morphology. Finite element analysis was done to evaluate the amount of stress and its distribution during orthodontic intrusive force. Results Overall maximum stress in this study was seen in the alveolar bone in the implant insertion area of 7.155 N/mm2. Maximum stress in the periodontal ligament was seen in middle third distocervical palatal root surface of the first molar (0.008993 N/mm2). Maximum stress in the enamel was seen in the distal aspect of the cementoenamel junction (0.423 N/mm2). Maximum stress in the dentin was observed in apical one-third of the mesiobuccal root surface of first molar (0.1785 N/mm2). Conclusion In this study with the use of palatal implant and transpalatal arch, we found that there was no tipping observed during intrusion. This study demonstrates that significant true intrusion of maxillary molars could be obtained in a wellcontrolled manner by using fixed appliances with microscrew implant as bony anchorage. How to cite this article Pavithra AS, Prashanth GS, Mathew S, Shekar SE. Analysis of Stress in the Periodontal Ligament and Alveolar Bone of the Maxillary First Molars during Intrusion with Microscrew Implants: A 3D Finite Element Study. World J Dent 2014;5(1):11-16.

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Predisposing factors for orthodontic mini-implant failure defined by bone strains in patient-specific finite element models

Orthodontic Waves ◽

10.1016/j.odw.2017.08.003 ◽

2018 ◽

Vol 77 (1) ◽

pp. 77-78

Keyword(s):

Finite Element ◽

Predisposing Factors ◽

Implant Failure ◽

Patient Specific ◽

Finite Element Models ◽

Bone Strains

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ORTHODONTIC PROCESS SAFETY EVALUATION BASED ON PERIODONTAL LIGAMENT CAPILLARY PRESSURE AND OGDEN MODEL

Journal of Mechanics in Medicine and Biology ◽

10.1142/s021951941840033x ◽

2018 ◽

Vol 18 (08) ◽

pp. 1840033 ◽

Cited By ~ 3

Author(s):

JINGANG JIANG ◽

ZHIYUAN HUANG ◽

XUEFENG MA ◽

YONGDE ZHANG ◽

YINGSHUAI HAN ◽

...

Keyword(s):

Finite Element ◽

Capillary Pressure ◽

Periodontal Ligament ◽

Alveolar Bone ◽

Safety Evaluation ◽

Finite Element Software ◽

Solid Models ◽

Biomechanical Simulation ◽

Force Range ◽

Orthodontic Forces

Taking the lower maxillary incisors as an example and the orthodontic forces along the near–far middle direction, the orthodontic forces along the crown–root direction and the orthodontic moment around the tongue–cheek direction as loading condition, the biomechanical simulation of the tooth is carried out by the method of finite element simulation in this paper. The CT images of the skull are segmented and denoised by Mimics. The solid models of teeth, periodontal ligament (PDL), alveolar bone and brackets are established by Gomagic and Solidworks. The material characteristics of the PDL are defined by the two-order Ogden hyperelastic model. Taking the PDL capillary pressure as a criterion for orthodontic safety, combined with the stress response of PDL, the safe orthodontic force range of mandibular central incisors is obtained by ANSYS finite element software.

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Time-dependent mechanical behaviour of the periodontal ligament

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/0954411001535525 ◽

2000 ◽

Vol 214 (5) ◽

pp. 497-504 ◽

Cited By ~ 57

Author(s):

W D van Driel ◽

E J van Leeuwen ◽

J W Von den Hoff ◽

J C Maltha ◽

A M Kuijpers-Jagtman

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Mechanical Behaviour ◽

Periodontal Ligament ◽

Alveolar Bone ◽

Element Model ◽

Time Dependent ◽

Step Response ◽

In Vivo Experiments

The process of tooth displacement in response to orthodontic forces is thought to be induced by the stresses and strains in the periodontium. The mechanical force on the tooth is transmitted to the alveolar bone through a layer of soft connective tissue, the periodontal ligament. Stress and/or strain distribution in this layer must be derived from mathematical models, such as the finite element method, because it cannot be measured directly in a non-destructive way. The material behaviour of the constituent tissues is required as an input for such a model. The purpose of this study was to determine the time-dependent mechanical behaviour of the periodontal ligament due to orthodontic loading of a tooth. Therefore, in vivo experiments were performed on beagle dogs. The experimental configuration was simulated in a finite element model to estimate the poroelastic material properties for the periodontal ligament. The experiments showed a two-step response: an instantaneous displacement of 14.10 ± 3.21 μm within 4 s and a more gradual (creep) displacement reaching a maximum of 60.00 ± 9.92 μm after 5 h. This response fitted excellently in the finite element model when 21 per cent of the ligament volume was assigned a permeability of 1.0 × 10−14m4/Ns, the remaining 97 per cent was assigned a permeability of 2.5 × 10−17 m4/N s. A tissue elastic modulus of 0.015 ± 0.001 MPa was estimated. Our results indicate that fluid compartments within the periodontal ligament play an important role in the transmission and damping of forces acting on teeth.

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The role of PDL-cementum enthesis in protecting PDL under masticatory loading: A finite element investigation

10.21203/rs.3.rs-315785/v1 ◽

2021 ◽

Author(s):

Hossein Jokar ◽

Gholamreza Rouhi ◽

Nabiollah Abolfathi

Keyword(s):

Computed Tomography ◽

Finite Element ◽

Periodontal Ligament ◽

Strain Energy Density ◽

Strain Energy ◽

Alveolar Bone ◽

Von Mises Stress ◽

Mechanical Stimuli ◽

Von Mises

Abstract PURPOSE. Function of periodontal ligament-cementum enthesis (PCE) in transferring mechanical stimuli within tooth-periodontium (PDT)-bone complex was not made clear yet. This study aimed to evaluate the effects of PCE on the mechanical stimuli distribution within the PDL and alveolar bone in the tooth-PDT-bone complex under occlusal forces using finite element method (FEM). METHODS. A computed tomography (CT) based model of alveolar bone and 2nd premolar of mandible was constructed, in which the PDT was considered at the interface of alveolar bone and tooth. Under a 3MPa distributed occluso-apical masticatory load, applied over the uppermost surface of crown, the von Mises strain (vMST) and strain energy density (SED) within PDL, and von Mises stress (vMSR) and SED within alveolar bone were calculated in two situations: 1. When the PCE was absent; and 2. When the PCE was present between the PDL and cementum. RESULTS. PCE levels-off the SED and vMST within PDL by maximum values of 92 kPa and 0.04 mm/mm, respectively, compared to the model without PCE. Moreover, it increased the alveolar bone SEDs and vMSR by maximum values of 0.36 kPa and 0.63 MPa, respectively, compared to the without PCE model.CONCLUSION. By including PCE in the tooth-PDT-bone model, the mechanical stimuli shift from PDL to its surrounding alveolar bone. Thus, it can be speculated that the tooth-PDT-bone complex has the capability of, through shifting excess mechanical stimuli from PDL toward the alveolar bone, reducing the risk of PDL damage.

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