Bioactive glasses were initially developed for bone grafting, and have been developed for use in BioMin F toothpaste to deliver a combination of Calcium, Phosphate and Fluoride ions to strengthen and protect tooth enamel through the production of Fluorapatite. These glasses are highly biocompatible. They're tiny too (10th of the width of a human hair), and as such they can penetrate the minute holes within the tooth and adhere to the surfaces of the mouth where they slowly release providing added protection for several hours.