Abstract

Background. Mechanical stress, which bone tissues receive, including under the influence of tongue pressure, has an important impact on their metabolism. Determination of the vector (tensor) of deformation, as well as the nature of stresses arising in the jaw growth zones can be carried out using simulation computer modeling based on the finite element method.
Aim: to conduct a comparative analysis of calculations of the stress-strain state of the patient's maxillofacial region using the finite element method.
Materials and methods. The research was based on the creation and calculations of mathematical models of the facial skull. The maximum displacement of the model nodes under the reproduced loading conditions (Total Deformation) was determined, and the nature of the distribution of stresses (Equivalent stress) and deformations (Equivalent elastic strain) was described with its normal tongue volume (model 1) and an increase in volume by 25% (model 2).
Results. With a normal tongue volume, the pattern of movement of the model nodes due to its pressure corresponded to the normal facial growth vector in the age period. They are crucial for growth and development, but the magnitude of the stresses was insignificant. The stress-strain state of the system qualitatively changed towards an increase in the displacements of the lower jaw nodes, namely, sagittal and external transverse, in the absence of an increase in the transverse displacements of the upper jaw nodes. We also noted characteristic changes in the displacement vectors of the nodes of the middle zone of the face from the top down (clockwise) to the bottom up (counterclockwise). A similar nature of the displacements under static loading conditions contributes to the formation of skeletal mesial (due to the predominant growth of the lower jaw), cross (due to the narrowing of the upper jaw) and open (due to changes in the displacement vectors of the nodes of the middle zone of the face) bites.
Conclusions. The maximum displacements of the model nodes on the upper jaw increased by 5.2 times with an increase in the volume of the tongue by 25%, on the lower jaw – by 9.7 times, and overall – by 6.5 times