Plast-press JV, the high pressure flask for processing plastic materials.

VACEK J. Dr. PhD.; * Department of Prosthetic Dentistry, 1st Faculty of Medicine, Charles University Prague, The Czech Republic


The conventional procedure of processing basal dental plastics by applying the flask method, used for almost sixty years and still favoured today, has several serious imperfections affecting the quality of the final product. These defects e.g. porosity, contraction cavities, thicker base plate, a relatively high percentage of free monomer etc. are caused by the rheological properties if the base materials and the classic method of the processing.

The aim of this presentation is to introduce a new type of flask, called PLAST-PRESS JV, working on the piston system and holding the high pressure constantly during the whole process of polymerization.

The results of our method show significantly better mechanical, chemical and biological properties of the final product against materials processed by the classic method.

The investigation was supported by the Grant UK No 162/94-95.