ABSTRACT
The aim of this study was to evaluate the stress distribution in the cervical region of a sound upper central incisor in two clinical situations, standard and maximum masticatory forces, by means of a 3D model with the highest possible level of fidelity to the anatomic dimensions. Two models with 331,887 linear tetrahedral elements that represent a sound upper central incisor with periodontal ligament, cortical and trabecular bones were loaded at 45º in relation to the tooth's long axis. All structures were considered to be homogeneous and isotropic, with the exception of the enamel (anisotropic). A standard masticatory force (100 N) was simulated on one of the models, while on the other one a maximum masticatory force was simulated (235.9 N). The software used were: PATRAN for pre- and post-processing and Nastran for processing. In the cementoenamel junction area, tensile forces reached 14.7 MPa in the 100 N model, and 40.2 MPa in the 235.9 N model, exceeding the enamel's tensile strength (16.7 MPa). The fact that the stress concentration in the amelodentinal junction exceeded the enamel's tensile strength under simulated conditions of maximum masticatory force suggests the possibility of the occurrence of non-carious cervical lesions such as abfractions.
Subject(s)
Humans , Bite Force , Dental Stress Analysis , Finite Element Analysis , Imaging, Three-Dimensional/methods , Incisor/physiology , Tooth Cervix/physiopathology , Compressive Strength , Dental Enamel/physiopathology , Reproducibility of Results , Software , Stress, Mechanical , Tensile StrengthABSTRACT
La sensibilidad dentinaria cervical (SDC) es una respuesta dolorosa a los estímulos térmicos, físicos y químicos en la región cervical del diente. La prevalencia reportada de esta condición clínica va desde un 8 a un 35 por ciento, según la población estudiada y la metodología para evaluar la SDC. La epidemiología es posbre respecto de los posibles factores causales. Para identificar estos factores causales y poder prevenir y tratar correctamente la SDC, es esencial contar con trabajos de investigación bien realizados, en grandes poblaciones, en las que se utilice una aceptable metodología estandarizada para la evaluación por medio de un cuestionario y para el examen clínico. En este trabajo se hace una revisión de la literatura actual con respecto a la prevalencia, etiología y distribución bucal de esta dificultosa condición