Pre-eruptive vs. Post-eruptive Fluoride
At the time of tooth eruption, enamel is not completely mineralized and will undergo a post-eruptive period (topical effect) of fluoride that will take approximately two years. Throughout this enamel maturation period, fluoride continues to accumulate in the outer surfaces of the enamel. This fluoride is derived from the saliva, as well as exposure to fluoride-containing products. Most of the fluoride incorporated into the developing enamel occurs during the pre-eruptive (systemic effect) period of enamel formation, but also occurs topically during the post-eruptive period of enamel maturation.