Masticatory Side-switch and Mixing Ability.

Overview

The main aim of this cross-over intervention study is to assess the effect of masticatory side-switch frequency on different aspects of masticatory function, including masticatory mixing ability and rhythm. A secondary aim is to explore the subjective perception of taste, muscular fatigue, and saliva production through a VAS. Thirty-six volunteers recruited for convenience, among students of the Degree of Dentistry of the Faculty of Medicine and Health Sciences of the University of Barcelona, will perform 6 tests, each consisting of 2 assays, chewing a two-coloured chewing gum, during 40 masticatory cycles. The tests will be randomised masticatory sequences of "free-style", "unilateral-right", "unilateral-left", switching the chewing side at 5% "G05", at 15% "G15" and at 25% "G25". Video recordings of these tests will be made to later assess, on slow playback, the change of the chewing side and the masticatory rhythm. The masticatory mixing ability will be determined through the scanning and posterior analysis of the red-channel in the histogram plug-in in "ImageJ" (R).

This this cross-over intervention study aims to assess the effect of masticatory side-switch frequency on different objective aspects of masticatory function, including masticatory mixing ability and rhythm, as well as the subjective perception of taste, muscular fatigue, and saliva production through a VAS. Each of the thirty-six volunteers recruited for convenience, among students of the Degree of Dentistry of the Faculty of Medicine and Health Sciences of the University of Barcelona, will perform 6 tests, each consisting of 2 assays, chewing a two-coloured chewing gum, during 40 masticatory cycles. One test involves freestyle mastication in which the participant will be asked to masticate the chewing gum. Two tests involve chewing the gum unilaterally (i.e., only on the right-hand side, and only on the left) varying the order of these assays. In the last three tests, the volunteer will switch chewing side in 5% (G05), 15% (G15), or 25% (G25) respectively; the sequence of the assays will be randomized. Twenty-four of these volunteers will be randomly selected to repeat these tests after a period of two weeks. The masticatory mixing ability will be determined through the "mixing capacity index" (MCI), obtained from through the scanning and posterior analysis of the red-channel in the histogram plug-in in "ImageJ" (R), and the masticatory rhythm will be assessed through the masticatory frequency as the ratio of masticatory cycle number to masticatory time. The control variables will include age and sex.