{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T06:36:51Z","timestamp":1776753411310,"version":"3.51.2"},"reference-count":54,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T00:00:00Z","timestamp":1776729600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>This study aimed to demonstrate the usefulness of digital image correlation (DIC) for analysing the activity and heterogeneity of the temporalis muscle based on its displacements. While the standard measure for superficial muscles traditionally relies on muscle force determined via electrical biopotentials and numerical simulations, this paper presents results indicating that a kinematic parameter (muscle displacement) can effectively assess muscle function.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      The temporalis muscle was selected as the primary object of investigation, with\n                      <jats:italic>in vivo<\/jats:italic>\n                      measurements taken on both the working and non-working sides during unilateral chewing of three selected foods. The study group consisted of 8 healthy adult males aged 36.6 \u00b1 9.4 years (BMI: 24.7 \u00b1 0.8\u00a0kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ). A Dantec Q400 non-contact measurement system based on DIC was utilised. Reference images were captured at the mandible\u2019s physiological resting position. The technique enabled continuous full-field mapping across the skin surface, while the final analysis was precisely confined to the area corresponding to the muscle fibres.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results and Discussion<\/jats:title>\n                    <jats:p>The study demonstrated that the temporalis muscle\u2019s functioning is complex and structurally heterogeneous. Specifically, the analysis revealed two distinct kinematic patterns: an asymmetric cycle (AC) in the anterior and middle parts responsible for force generation, and a fluctuating cycle (FC) in the posterior part serving as a dynamic stabiliser for the temporomandibular joint (TMJ). Furthermore, muscle kinematics were significantly modulated by both the chewing side and food texture. Spatial activation patterns suggest a task-specific biomechanical strategy, where the working side presses the mandible, while the non-working side stabilises it against excessive rotation. Ultimately, the results confirm that skin surface displacement can serve as a reliable, high-resolution measure of temporalis muscle activity.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fbioe.2026.1767695","type":"journal-article","created":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T05:36:50Z","timestamp":1776749810000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Application of digital image correlation to study the activity and functional heterogeneity of the human temporalis muscle in vivo during unilateral chewing: a preliminary study"],"prefix":"10.3389","volume":"14","author":[{"given":"Przemys\u0142aw","family":"Str\u00f3\u017cyk","sequence":"first","affiliation":[{"name":"Department of Mechanics, Materials and Biomedical Engineering, Wroclaw University of Science and Technology","place":["Wroclaw, Poland"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,21]]},"reference":[{"key":"B2","doi-asserted-by":"publisher","first-page":"404","DOI":"10.1016\/j.jmbbm.2017.01.048","article-title":"A personalized 3D-printed prosthetic joint replacement for the human temporomandibular joint: from implant design to implantation","volume":"69","author":"Ackland","year":"2017","journal-title":"J. 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