Journal of Dental Research, Vol 74, 1715-1720, Copyright © 1995 by International & American Associations for Dental Research Online Journals
The site-specificity of supragingival calculus deposition on the lingual surfaces of the six permanent lower anterior teeth in humans and the effects of age, sex, gum-chewing habits, and the time since the last prophylaxis on calculus scores
L. M. Macpherson, D. C. Girardin, N. J. Hughes, K. W. Stephen and C. Dawes
University of Glasgow Dental School, UK.
The hypotheses to be tested were: (i) that chewing sugar-free gum
frequently and for long periods would be associated with higher amounts of
supragingival calculus, and (ii) that there would be no site-specificity of
calculus deposition on the lingual surfaces of the 6 lower anterior teeth.
Subjects, 436 in Glasgow and 191 in Winnipeg, were scored for calculus at
mesial, lingual, and distal sites on the lingual surface of each of the 6
lower anterior teeth, by the Volpe-Manhold method. They also answered
questions on the time since the last prophylaxis, the frequency of gum
chewing, the type of gum chewed, and the length of a typical gum-chewing
episode. A subset (233) of the Glasgow subjects were scaled and re-scored
for calculus 3 months later. When the data for the logarithmic
transformations of the initial calculus scores were subjected to stepwise
multiple-regression analysis, the only factor which correlated
significantly with initial calculus scores in both cities was the time
since the last prophylaxis. In the Glasgow subjects scored 3 months after a
prophylaxis, there was a negative correlation between chewing sugar-free
gum and calculus scores, whereas in the Winnipeg subjects, age and the
chewing of sucrose-containing and sugar-free gum were positively correlated
with calculus scores. Thus, the results were contradictory with respect to
the first-tested hypothesis. The calculus distribution patterns were very
similar in the subset of Glasgow subjects and the Winnipeg subjects, with
the amounts on the lateral incisors and canines averaging 70.2% and 44.5%,
respectively, of those on the central incisors. Thus, the second hypothesis
was disproved.
