EFFECT OF TOOTHPICKS WITH AND WITHOUT FLUORIDE ON DEMINERALIZATION AND REMINERALIZATION OF ENAMEL AND DENTIN IN-SITU

The aim of this investigation was to study the effect of the interprox imal use of fluoride (F)-impregnated and non-impregnated birch toothpi cks on the degree of de- and remineralization of enamel and dentine in situ. Ten volunteers with complete dentures in the upper jaw particip ated. Each subject had four specimens: (1) sound enamel, (2) demineral ized enamel, (3) sound dentine and (4) demineralized dentine; placed p airwise at two approximal sites (15/16 and 25/26) of the maxillary pro sthesis. The study involved three test periods (A, B and C), each last ing 4 weeks. In A, the subjects used F toothpicks (impregnated in 4% N aF) and, in B, nonimpregnated toothpicks 3 times daily. During period C, no toothpicks were used. Dentifrice or other F-containing products were not allowed during the 4-week periods. Transversal microradiograp hy was used to determine lesion depth (ld) and mineral loss (Delta Z). The results revealed that all the sound samples lost mineral during t he three experimental periods; Delta Z for both enamel and dentine was less for A and B compared with C (p < 0.01) and less for A compared w ith B and C for dentine (p < 0.05, p < 0.01). The demineralized sample s also lost mineral, apart from dentine, during periods A and B, i.e. when F-impregnated and non-impregnated toothpicks were used; Id for en amel and Delta Z for dentine were less for A compared with C (p < 0.05 ). Four weeks' use of toothpicks, especially F-impregnated toothpicks, thus reduces the demineralization of enamel and dentine at approximal sites in situ.