Masticatory path pattern and masticatory performance while chewing gummy jelly.

The purpose of this study was to clarify masticatory path pattern and masticatory performance during gummy jelly chewing. A total of 235 healthy adults were asked to chew gummy jelly for 20 s on each side, and the masticatory movement was recorded using a Motion Visi-Trainer (MVT V1). Next, the amount of glucose extraction was measured as a parameter of masticatory performance. The masticatory path was classified into one of five patterns newly devised: normal pattern (N, opening: straight or concave, closing: convex) and abnormal patterns (A1-A4). The number of occurrences of each pattern was investigated and compared by sex and path pattern. Next, masticatory performance was compared between the normal pattern and the abnormal patterns by sex. Pattern N was the most frequently expressed in 346 cases out of 470 cases (73.6%), followed by patterns A1, A4, A2, and A3 in that order. Regarding the number of patterns observed, pattern N was the most common in both sexes, followed by pattern A1, with no significant difference between sexes. The amount of glucose extraction in each pattern was the highest in pattern N for both sexes, followed by A2 and others in that order, and a significant difference was observed between the normal pattern and the abnormal patterns. From these results, the existence of sex difference in masticatory path patterns during gummy jelly chewing was not proven, and that masticatory performance was higher with normal patterns than with abnormal patterns.

Path pattern and movement during mastication on habitual and non-habitual chewing sides.

PURPOSE: To clarify the presence or absence of differences in path pattern and movement during mastication between the habitual and non-habitual chewing sides. METHODS: Participants were 225 healthy adults with natural dentition. Mandibular movement while chewing gummy jelly on each side was recorded, and masticatory path pattern was classified into five types (one normal and four abnormal). The frequency of each pattern was measured and compared between chewing sides. The amount, rhythm, velocity, and stability of movement and masticatory performance were measured and compared between chewing sides. RESULTS: A normal pattern was observed on the habitual chewing side in 84.4% of participants. There was a significant difference between chewing sides in masticatory path pattern (χ2 = 35.971, P < 0.001). Values of parameters regarding the amount and velocity of movement and masticatory performance were significantly higher on the habitual chewing side. Values of parameters regarding rhythm and stability of movement were significantly lower on the habitual chewing side. CONCLUSION: The present findings of functional differences between chewing sides in terms of path pattern and movement during mastication suggest that these factors should be analyzed on the habitual chewing side.

Association between masticatory movement and oral and physical function in healthy older women.

PURPOSE: This study examined the association between masticatory movement and oral and physical function in healthy older women using clinical assessments considering central motor control. METHODS: A total of 107 independent older women (mean age, 74.37 ± 4.46 years; age range, 66-84 years) living in the community participated in this cross-sectional study. The subjects selected were those aged 65 years or older with at least 28 teeth and without oral dysfunction, temporomandibular joint (TMJ) disease, cerebrovascular disease, or neuromuscular disease. The following items of oral and physical function were measured: masticatory path pattern, masticatory performance, oral diadochokinesis (ODK), tongue pressure, single-leg stance with eyes open (SLS), stepping test, and grip strength. Logistic regression analysis adjusting for age was performed to investigate the association between masticatory movement and other items. RESULTS: In total, 30.8% of subjects were classified into the abnormal group regarding masticatory path pattern, having a significantly lower value than that of the normal group in masticatory performance (unadjusted p = 0.021). After adjusting for age, the masticatory path pattern was significantly associated with masticatory performance ( p = 0.032); ODK /pa/ ( p < 0.001), /ta/ ( p = 0.022), and /ka/ ( p = 0.016); and stepping test ( p = 0.018). Tongue pressure, SLS, and grip strength were not significantly associated with masticatory path pattern. CONCLUSION: Masticatory movement in older women was associated with masticatory performance, tongue and lip motor skills, and physical agility, which might be influenced by central motor control.