Only studies with the following cha

Only studies with the following characteristics were eligible for review:
(1) the study participants must have consumed candies or lozenges con-
taining xylitol; (2) there were no restrictions on study populations; (3)
the control group included subjects who either had not received any
type of intervention or had received a placebo or preventive procedures
(eg, dental sealants, oral health instruction); and (4) the study provided
concurrent comparisons of coronal dental caries increment using decayed,
missing, and filled surfaces (DMFS). Only clinical trials conducted with hu-
man subjects were included in the review. Trials that allocated other prod-
ucts (eg, chewing gum, chlorhexidine) to the treatment group, in addition
to the xylitol-based candies and lozenges, were excluded.
Once eligible studies were identified, the authors extracted the following
information from each report: (1) citation and year of publication; (2) lo-
cation of trial; (3) sample size; (4) study design; (5) baseline and follow-up
DMFS scores; (6) concentration of and frequency of exposure to xylitol; (7)
type of sweeteners used in the control group; (8) study setting; (9) caries
risk statuses for treatment and comparison groups and method of estima-
tion; (10) methods of caries diagnosis; (11) assessments of participant su-
pervision and compliance; (12) use of other caries prevention strategies;
and (13) frequency of side effects.