Pellicle formation on hydroxyapatite splints attached to the human dentition: Morphologic confirmation of the concept of adsorption

The formation of pellicle was studied using epoxy resin splints with hydroxyapatite crystals at the surface. The splints were attached to the buccal surfaces of molar and premolar teeth of human test subjects and removed after 2 hr. Specimens were processed for transmission and scanning electron microscopy. An incomplete pellicle of uneven thickness characterized by small projections of organic material partly covered the hydroxyapatite areas of the splint surface. Only traces of such pellicle occurred on the resin surfaces. The findings support the concept that the first stage in the formation of an acquired pellicle occurs as an adsorption of salivary components to hydroxyapatite crystals on the tooth surface.