Abstract: This invention describes compositions containing nano-crystalline apatite useful as bone—or preferably as tooth restorative materials. The materials produced, using the composition have improved properties in the areas of esthetics, hardness, translucency, surface polishability, strength and the capability to release and to take ions up in respect of a biological environment.

Abstract: Collection of artificial front teeth which, in important sizes classes, comprises three groups of shapes which differ in terms of the relationships of the mesiodistal widths of their vestibular surfaces in the cervical, central and incisal thirds of their length, namely: a cervically accentuated group in which the said widths are approximately identical, a centrally accentuated group in which the width in the central third is greater than the width in the cervical third by at least the factor 1.15, and the width in the incisal third is not greater than the width in the central third, and an incisally accentuated group in which the width in the incisal third is greater than the width in the cervical third at least by the factor 1.18 and the width in the central third is smaller than the width in the incisal third.