APF and dentifrice effect on root dentin demineralization and biofilm

Because dentin is more caries-susceptible than enamel,its demineralization may be more influenced by additional fluoride (f). we hypothesized that a combination of professional f,applied as acidulated phosphate f (apf),and use of 1100-ppm-f dentifrice would provide additional protection for dentin compared with 1100-ppm-f alone. twelve adult volunteers wore palatal appliances containing root dentin slabs,which were subjected,during 4 experimental phases of 7 days each,to biofilm accumulation and sucrose exposure 8x/day. the volunteers were randomly assigned to the following treatments: placebo dentifrice (pd),1100-ppm-f dentifrice (fd),apf + pd,and apf+fd. apf gel (1.23% f) was applied to the slabs once at the beginning of the experimental phase,and the dentifrices were used 3x/ day. apf and fd increased f concentration in biofilm fluid and reduced root dentin demineralization,presenting an additive effect. analysis of the data suggests that the combination of apf gel application and daily regular use of 1100-ppm-f dentifrice may provide additional protection against root caries compared with the dentifrice alone. © 2011 international & american associations for dental research.