Contribution of individual muscle action to bone stress in the facial skeleton during bilateral clenching

摘要

Stresses in the human facial skeleton arising from habitual activities such as clenching are of interest when investigating facial fractures, orthodontic modification, and bone remodeling. Maximum principal stresses during clenching have beenquantified in the mandible using finite element analyses (1, 2). However, for the remainder of the facial skeleton, these analyses have only been performed for orthodontic loading (3) and only qualitative descriptions of stress have been reported based on photoelastic analysis for clenching (4). Thus, there is a shortage of quantitative information on stress distributions in the facial skeleton for habitual loading. Further, it is unknown to what extent the individual masticatory muscles contribute tostresses in the facial bones. This information would benefit surgeons and researchers since it would establish which muscles are critical to normal function from a bone stress perspective.In order to improve understanding of stresses in the facial skeleton for habitual activities, the objectives of this study were to: 1) quantitatively determine stresses in the facial skeleton during maximal clenching; and 2) determine the relativecontribution of each of the four primary masticatory muscles to these stresses.