Posttreatment benefits from participation in a school-based fluoride mouthrinsing program: II. Results after three to five years of rinsing.

The effect on caries prevalence of previous participation in a school-based 0.2 percent neutral NaF mouthrinsing program was assessed in junior-high-school students. The subjects had rinsed for three-to-five years as elementary-school students in the Three Village fluoride mouthrinsing program, Long Island, New York (F less than or equal to 0.1 ppm). The effects of rinsing were determined by comparing the caries prevalence of seventh, eighth, and ninth grade students who had previously participated in the rinsing program to the baseline caries scores of seventh through ninth grade students who were examined before the rinsing program began. The caries prevalence of the children who had participated in the rinsing program was 29.3 percent (DMFT) and 32.7 percent (DMFS) less than that of the children who had never rinsed. Preferential protection was afforded to the proximal surfaces which had a caries reduction of 56.1 percent compared to 28 percent for both the occlusal and buccolingual surfaces. The duration of the children's participation in the mouthrinsing program generally was related to the level of posttreatment benefits, although age upon entry into the program may also exert an influence. It is fortuitous that there is a persistence of mouthrinsing benefits since older children have generally been reluctant to give their full cooperation in a school-based fluoride mouthrinsing program.