Journal of Dental Research, Vol 64, 1229-1232, Copyright © 1985 by International & American Associations for Dental Research Online Journals
The effect of swallowing frequency on oral sugar clearance and pH changes by Streptococcus mitior in vivo after sucrose ingestion
F. Lagerlof and C. Dawes
A theoretical study of oral sugar clearance (Caries Res 17:321-334, 1983)
suggested that the unstimulated salivary flow rate (UNSTFR) and the volume
of saliva present in the mouth before swallowing (VMAX) can greatly affect
the rate of sugar clearance. The object of this study was to determine
whether variations in UNSTFR, by water infusion into the mouth, and in
VMAX, which can be altered by varying the swallowing frequency, would
influence sugar clearance and whether changes in VMAX would affect the
extent of the pH fall produced by S. mitior in vivo after sucrose
consumption. In three experiments on each of ten adult subjects, UNSTFR was
measured initially (mean value = 0.55 ml/min), and a swallowing schedule
was calculated so that the volumes swallowed were either 0.3 ml or 1.0 ml.
After a 10-second rinse with 20 ml of a 10% sucrose solution, the subjects
maintained a swallowing frequency such that the volumes swallowed were
either 0.3 ml or 1.0 ml at normal UNSTFR or were 0.3 ml when UNSTFR was
increased by infusing water at 0.5 ml/min. In all subjects, clearance of
sugar was faster at the higher swallowing frequency and at the higher flow
rate, as predicted by the theoretical model. Small acrylic splints were
made to fit over the lower incisors of ten subjects and to hold in the
floor of the mouth an antimony microelectrode covered by a 0.5-mm layer of
S. mitior, which was held in place by a dialysis membrane.(ABSTRACT
TRUNCATED AT 250 WORDS)
