Relation between teeth clenching and grip force production characteristics

Abstract

This study investigated the possible contributing effect of oral motor function on maximal and explosive grip force production characteristics. Fourteen healthy male subjects (age 22.5 +/- 2.1 years) were asked to exert maximal explosive grip strength with their dominant hands under the following four conditions: 1. Teeth clenching before and during grip strength exertion (C-C), 2. Teeth clenching before grip strength exertion and mandibular resting position during grip strength exertion (C-R), 3. Mandibular resting position before grip strength exertion and teeth clenching during grip strength exertion (R-C), and 4. Mandibular resting position before and during grip strength exertion (R-R). Maximal force (maxF), average force for every 0.1 s (aveF), maximal rate of force development (maxRFD) and time required to reach 90% of maxF (T 90% max) were analyzed for 1 s from the onset of grip force production. MaxF under C-C and R-C were significantly greater than that under R-R by 12.1% and 12.3%, respectively. AveF under C-C was significantly greater by 10.0-41.2% than that under R-R for all ten periods. AveF under C-R was significantly larger by 9.8-19.0% than that under R-R conditions from 0 to 0.4 s. Compared with under R-R conditions, maxRFD under C-C and C-R increased by 15.8% and 8.5%, respectively, and T 90% max under C-C, C-R and R-C decreased by 22.3%, 12.3% and 12.8%, respectively. These findings suggest that oral motor functions such as teeth clenching may influence not only maximal grip strength generation but also the rapidity of grip force production.