The Location of the Center of Rotation of the Maxillary Central Incisor during Stage III of the Begg Technique: A Finite Element Study

ABSTRACT Aim This finite element study was conducted to calculate the distribution of stresses in the periodontal ligament when various orthodontic forces were applied, with emphasis on the effect on root apex. Materials and methods An in vitro finite element method was used to construct a three-dimensional finite element model of a maxillary central incisor, its periodontal ligament and alveolar bone was constructed on the basis of average anatomic morphology. To this model, five types of orthodontic forces namely tipping, bodily movement, intrusion, extrusion and rotations were applied at various points on the crown of the tooth model. After the application of the forces, initial stress and initial displacements of the periodontal ligament were evaluated. The principal stress obtained on the periodontal ligament due to various orthodontic loadings on the maxillary central incisor was analyzed using ANSYS 10 finite element software. Results It showed that the greatest amount of relative stress at the apex of maxillary central incisor occurred with intrusion, extrusion and rotation. Bodily movement and tipping forces produce stress concentrated at the alveolar crest and not at the root apex. Conclusion Clinical implications of this study suggest that if the clinician is concerned about placing heavy stresses on the root apex, then vertical and rotational forces must be applied with caution. Clinical Significance If heavy stresses are to be placed on the root apex, then vertical and rotational forces must be applied with caution during orthodontic therapy. How to cite this article Mathur AK, Gupta V, Sarmah A, Pai VS, Chandrashekar G. Apical Force Distribution due to Orthodontic Forces: A Finite Element Study. J Contemp Dent Pract 2011;12(2):104-108.

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A Comparative Evaluation of Stress Distribution by Three Different Designs of Prefabricated Metal Posts on Endodontically Treated Permanent Maxillary Central Incisor: A Three-dimensional Finite Element Study

Journal of Contemporary Dentistry ◽

10.5005/jp-journals-10031-1121 ◽

2015 ◽

Vol 5 (3) ◽

pp. 123-130

Author(s):

Jyoti Nadgere ◽

Ganesh Pandurang Mengal

Keyword(s):

Finite Element ◽

Stress Distribution ◽

Comparative Evaluation ◽

Three Dimensional ◽

Central Incisor ◽

Maxillary Central Incisor ◽

Finite Element Study ◽

Dimensional Finite Element ◽

Three Dimensional Finite Element ◽

Element Study

ABSTRACT Purpose of the study: This study intends to evaluate and compare the stress distribution by three designs of prefabricated metal posts, parallel post (EG post), parallel post with coronal flare (i-post) and a tapered post (Filpost) in endodontically treated permanent maxillary central incisor. This study will help the dentists to choose the post that would generate the least stress in endodontically treated teeth. Procedure Three-dimensional (3D) finite element models were developed. The physical models include composite resin core material, dentin, endodontic post, luting cement and guttapercha. They were subjected to compressive load of 100 N at 135° angle with respect to longitudinal axis of tooth, above the level of cingulum, simulating the load condition in oral cavity and the effects of three posts on stress distribution, in endodontically treated maxillary central incisor was evaluated. Results Stress distribution was found to be better in the models having parallel post and parallel post with the coronal flare. Coronal flare has an added advantage of better fit in the root canal. Conclusion It was found that the stresses in maxillary central incisor with the parallel post with coronal flare were well distributed. How to cite this article Mengal GP, Nadgere J, Ram SM, Shah N. A Comparative Evaluation of Stress Distribution by Three Different Designs of Prefabricated Metal Posts on Endodontically Treated Permanent Maxillary Central Incisor: A Three-dimensional Finite Element Study. J Contemp Dent 2015;5(3):123-130.

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