Tooth displacement due to occlusal contacts: a three‐dimensional finite element study

Abstract

The use of the Finite Element Method (FE) is an appropriate way to study occlusal forces and tooth movement. The purpose of this study was to evaluate the effects of different occlusal contact patterns on tooth displacement in an adult dentition using a three-dimensional FE model of a human maxilla and mandible. Initially, images of a computerized tomography scan were redrawn in a computer program (CATIA) followed by the FE mesh construction. The MSC/Patran software was used to develop the FE mesh comprising 520,445 elements and 106,633 nodes. The MSC/Nastran program was utilized as pre and post-processor for all mathematical calculations necessary to evaluate dental and mandibular biomechanics. Four occlusal patterns were tested: FEM 1 - standard occlusal contacts; FEM 2 - removal of mesial marginal and mesial tripoidism contacts; FEM 3 - removal of distal marginal and distal tripoidism contacts; FEM 4 - similar to FEM 3 with added contacts between upper and lower incisors. Small changes in the standard distribution of occlusal contacts resulted in an imbalance of occlusal forces and changes in dental positioning. All simulations tested showed mesial displacement of posterior teeth. The most significant changes were registered in the model presenting unstable occlusal contacts when the anterior teeth were in occlusion (FEM 4). These findings may explain mandibular incisors crowding and maxillary incisors flaring as a result of small variations in dental contacts.

Orthodontic Force and Tooth Movement With and Without Occlusal Loads: 3D Analysis Using Finite Element Method

“…In 2006, Gomes de Oliveira et al (20) evaluated the effects of different occlusal contact patterns on tooth displacement in an adult dentition using a three-dimensional FE model of a human maxilla and mandible. Small changes in the standard distribution of occlusal contacts resulted in an imbalance of occlusal forces and changes in dental positioning.…”

Evolución de la patología oclusal. Una revisión de la literatura.

“…Además encontraron que si se presentan movimientos excén-tricos que se hacen a expensas del contacto de uno o más dientes (función de grupo) no se generan afecciones al sistema, por el contrario, disminuyen las cargas condilares en el lado de trabajo y no trabajo. A través de un estudio de elementos finitos 88 , donde se evaluó el efecto de diferentes fuerzas de contacto sobre el desplazamiento de los dientes, se determinó que una oclusión inestable, con puntos de contacto inestables, al ser comparada con una oclusión estable y con mejor distribución de puntos de contacto, presentaba cambios significativos en la armonía dental, generando: mayor movilidad dental, inestabilidad funcional oclusal y movimientos excéntricos patológicos; esto a su vez generaba alteraciones neuromusculares y articulares. La presencia de puntos de contacto mejor distribuidos permitían la correcta absorción y dispersión de cargas oclusales.…”

Three-dimensional finite element modeling from CT images of tooth and its validation

“…This study shows that an FE model of a tooth can be reconstructed through geometry-based modeling, in which a combination of several commercially available computer-aided techniques are used to extract geometrical information from CT data and to generate the model. Previously, several successful works on FE modeling of teeth from CT data have applied some efficient geometry extraction-CAD modeling combinations [11][12][13]16) . Such combinations might result in a considerable reduction in the time consumed in creation of FE models, as compared with traditional methods of modeling from CT data.…”

“…Recently, an image acquisition method using computed topography (CT) has been extensively applied as a scanning tool for 3D-digitizing purposes in modeling of teeth [9][10][11][12][13][14][15] , providing higher accuracy, faster digitization and finer description. In addition, several pioneering modeling techniques for CT data have been originally developed as in-house programs to extract the model geometry, because this method requires the extraction of inner and outer contours from CT data of teeth [7][8][9][10] .…”

“…In addition, several pioneering modeling techniques for CT data have been originally developed as in-house programs to extract the model geometry, because this method requires the extraction of inner and outer contours from CT data of teeth [7][8][9][10] . More recently, several computer-aided techniques to extract the geometry have become commercially available with the industrial development of 3D image processing and reverse engineering techniques, facilitating the construction of FE models [11][12][13][14][15] . Validation of the FE model, one of the important problems in FE analysis 17,18) , has been previously reported by experimental verification through comparison of the results with those of laboratory or clinical tests of the teeth [18][19][20][21][22][23][24][25] .…”