The aim of this study was to develop a wax suitable to serve as a func
tional impression material. Several binary mixtures of paraffin, beesw
ax and rosin were prepared. They were characterized by differential th
ermal analysis (DTA), and tested for plastic deformation, thermal expa
nsion, detail reproduction and mechanical properties. It was found tha
t the combinations of paraffin with rosin can function well as impress
ion materials, as they combine a high value of plastic deformation at
37 degrees C with relatively low values at room temperature. Concentra
tions of rosin as small as 1% or 2% are adequate to produce this resul
t. The flow of paraffin was significantly reduced by the addition of b
eeswax. A linear relationship was found between the 37 degrees C flow
values of paraffin-beeswax mixtures and the proportions of the ingredi
ents.