Control of octacalcium phosphate and apatite crystal growth by amelogenin matrices

Tooth enamel, the hardest bioceramic composite in the vertebrate body, is the result of a cascade of intra- and extracellular events. Amelogenins, the principal extracellular matrix protein component of mineralizing enamel, have been considered to play substantial roles in controlling the growth and organization of enamel crystals. Considering octacalcium phosphate (OCP) as a precursor phase of enamel apatite crystallites, we have developed in vitro systems to grow OCP and apatite crystals in amelogenin matrices and therefore to investigate amelogenin–OCP and amelogenin–apatite interactions. This paper reviews our current findings on the effect of amelogenin on the morphology, size, phase and orientation of such crystals.