title: The effects of chewing frequency and duration of gum chewing on salivary flow rate and sucrose concentration.
abstract: On ten separate occasions, unstimulated saliva was collected from 12 adults and then eight samples of saliva over a 20-min period while chewing, in random order, 3 g of either Wrigley's Spearmint chewing-gum or gum-base at frequencies of 35, 50, 70, 90, or 130 chews/min. With both stimuli, flow rates peaked in the first minute of stimulation and then fell with time. A repeated-measures analysis of variance showed that for both the gum and the gum-base, flow rates were independent of chewing frequency, except during the first minute with the chewing-gum. The gum elicited a significantly higher flow rate over the first 4 min of chewing, while the base elicited a significantly higher flow rate over the 8-20-min period of chewing. The sucrose concentration in saliva was also independent of chewing frequency. The salivary sucrose concentration peaked during the second minute of chewing (mean +/- SE = 424.7 +/- 20.0 mM) and the concentration then fell progressively with time. However, sucrose was still being released into saliva during the 15-20 min period of chewing (12.6 +/- 0.8 mM). Gum-base which had been chewed without access to saliva was softer than unchewed base but showed no change in filler content or a reduction in the average molecular weight. The decrease in hardness of the chewed gum-base may have resulted from improved mixing of heterogeneous phases and increased dispersion of plasticizing agents.
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Manitoba, Winnipeg, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Dong
authors.forename: A D
authors.initials: AD
authors.lastname: Puckett
authors.forename: C
authors.initials: C
authors.lastname: Dawes
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002638:Chewing Gum; D005260:Female; D006244:Hardness; D006801:Humans; D008297:Male; D008409:Mastication / Q000502:physiology*; D008875:Middle Aged; D012463:Saliva / Q000737:chemistry; D012472:Salivation / Q000502:physiology*; D012636:Secretory Rate; D018709:Statistics, Nonparametric; D013395:Sucrose / Q000032:analysis; D013997:Time Factors
chemical_list: D002638:Chewing Gum; D013395:Sucrose