Scanning Electron Microscopy of the Surface of Developing Mammalian Dental Enamel

Abstract

THE surface of the developing dental enamel of the manatee (Trichecus latirostris) and the monkey (Rhesus macacus) has been examined directly in a scanning electron microscope. Molar tooth germs were dissected from the jaws of these animals soon after death. Specimens were prepared by gently stripping off the enamel organ from the surface of the developing tooth, thus exposing the developing front of the enamel. The pulp was then removed from the centre of the developing tooth, which was divided into convenient portions and allowed to dry. These portions were fixed with ‘Araldite’ adhesive to aluminium specimen stubs leaving the enamel side exposed. The specimens were finally covered with a 300-Å thick layer of aluminium to render their surfaces conducting. They were examined in a scanning electron microscope (a developmental model built by the Cambridge Instrument Co., Cambridge, England). The micrographs were taken with a 15-kV scanning electron beam and only the high-energy reflected electrons were used to form the images.