{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T07:24:23Z","timestamp":1790061863952,"version":"4.0.1"},"reference-count":52,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T00:00:00Z","timestamp":1761004800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>This study investigated bite force changes after botulinum toxin type A (BoNT-A) injection into different masticatory muscles. Thirty-five male participants were divided into three groups: masseter only (M), masseter and temporalis (MT), and masseter, temporalis, and medial pterygoid (MTP). Bite force was measured before and up to 6 months after injection with the Dental Prescale II system. Baseline values showed no significant group differences. Group M exhibited significant reduction at 1 and 2 weeks, with recovery within 1 month. Group MT showed a similar transient decrease, also recovering after 1 month. In contrast, Group MTP demonstrated a more pronounced and prolonged reduction, persisting up to 4 months before recovery. These results indicate that the extent and duration of BoNT-A effects depend on the number of muscles injected. Multi-muscle injections, including the medial pterygoid, provide more durable suppression. However, further research involving patient populations is needed to clarify whether multi-muscle injection strategies provide therapeutic benefits in clinical conditions such as temporomandibular disorders or oromandibular dystonia.<\/jats:p>","DOI":"10.3390\/toxins17100519","type":"journal-article","created":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T14:53:19Z","timestamp":1761058399000},"page":"519","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["The Effective Way of Botulinum Toxin Injection to Reduce Bite Force: Preliminary Study"],"prefix":"10.3390","volume":"17","author":[{"given":"Kun-Hwa","family":"Kang","sequence":"first","affiliation":[{"name":"Department of Oral Medicine, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jae-Kwang","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Oral Medicine, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin-Seok","family":"Byun","sequence":"additional","affiliation":[{"name":"Department of Oral Medicine, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1326-3948","authenticated-orcid":false,"given":"Ji Rak","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Oral Medicine, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea"},{"name":"Craniofacial Nerve-Bone Network Research Center, Kyungpook National University, Daegu 41940, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6","DOI":"10.11607\/ofph.3023","article-title":"Botulinum Toxin for Treating Temporomandibular Disorders: What Is the Evidence?","volume":"36","author":"Delcanho","year":"2022","journal-title":"J. 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