Repeated clenching causes plasticity in corticomotor control of jaw muscles

• DOI: 10.1111/eos.12101
• Publication Date: 2013-11-20T09:14:53Z
• Authors: Takashi Iida; Osamu Komiyama; Ryoko Obara; Lene Baad‐Hansen; Misao Kawara; Peter Svensson
• Keywords: Stimulus (psychology); Silent period; Repeated measures design; Motor Control

This study tested the effect of short‐term tooth‐clenching on corticomotor excitability masseter muscle using transcranial magnetic stimulation ( TMS ). Fifteen subjects with normal stomatognathic function participated. All performed a task TCT ) five consecutive days. The consisted 10, 20, and 40% maximum voluntary contraction in randomized order within 1 h. underwent four sessions: pretask day (baseline), post‐task 1, 5, 5. Motor‐evoked potentials MEP s) from first dorsal interosseous FDI muscles were obtained sessions. Motor thresholds decreased, after , for s. Masseter s dependent stimulus intensity session, whereas only intensity. Post‐hoc T ukey tests demonstrated significantly higher 5 80 90% above when compared pre‐ values. Our results suggest that performance repeated can trigger neuroplastic changes control jaw‐closing such may contribute to mechanism underlying clinical manifestations tooth clenching.