Dental and Medical Problems

Dent Med Probl
Index Copernicus (ICV 2021) – 132.50
MEiN – 70 pts
CiteScore (2021) – 2.0
JCI (2021) – 0.5
Average rejection rate (2022) – 79.69%
ISSN 1644-387X (print)
ISSN 2300-9020 (online)
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Dental and Medical Problems

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doi: 10.17219/dmp/154777

Publication type: original article

Language: English

License: Creative Commons Attribution 3.0 Unported (CC BY 3.0)

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Dejak B, Bołtacz-Rzepkowska E. Mechanism of enamel damage in the grooves of molars during mastication [published online as ahead of print on February 20, 2023]. Dent Med Probl. doi:10.17219/dmp/154777

Mechanism of enamel damage in the grooves of molars during mastication

Beata Dejak1,A,B,C,D,E,F, Elżbieta Bołtacz-Rzepkowska2,D,F

1 Department of Prosthetic Dentistry, Medical University of Lodz, Poland

2 Department of Conservative Dentistry, Medical University of Lodz, Poland


Background. During mastication, molars are subjected to heavy stress. However, a full explanation of the effects of physiological loads on tooth structures is lacking.
Objectives. The study aimed to determine stress in molars and identify the mechanism of enamel damage in the grooves of the teeth during computer-simulated mastication.
Material and methods. The study was carried out using the finite element method (FEM). A three-dimensional (3D) model of the first mandibular molar and of the crown of the opposing maxillary tooth was created. A food bite was introduced between the antagonistic teeth. The mastication cycle of the bolus was computer-simulated. The equivalent stress in the enamel and dentin of the mandibular molar was calculated according to the modified von Mises (mvM) criterion.
Results. During the simulated chewing activity, the highest equivalent mvM stress and tensile stress concentrated on the molar enamel around the central groove and the foramen cecum. The value of the equivalent mvM stress was close to the tensile strength of the enamel. According to the mvM criterion, the enamel in these areas was exposed to destruction, which coincided with the occurrence of class I caries.
Conclusions. During mastication, significant tensile and mvM stress concentrates on the mandibular molar enamel around the central groove and the foramen cecum. High stress in these areas may cause prism microfractures and facilitate the bacterial penetration of the enamel.

Key words

finite element analysis, modified von Mises failure criterion, enamel damage, biomechanical causes of caries, simulation of mastication

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