Abstract: A method for using dental acrylic resins, the method comprising mixing a liquid monomer of methyl methacrylate with a polymer powder of methyl methacrylate, forming the mixture into an arbitrary shape by molding, filling, applying or other means, and then polymerizing and curing the formed mixture, wherein organic compounds selected from acryloyl morpholine, a coumarone resin, vinyl stearate, polyvinyl acetate, and alcoholic surfactants are previously added to the liquid monomer as a shrinkage controlling agent for lowering a curing shrinkage caused by the polymerization, is disclosed. According to the invention, not only the curing shrinkage rate of the curing shrinkage generated at the time of polymerization can be readily lowered to 0.3% or less, but also the method of the invention can be applied to a denture, a denture base, a casting pattern, fillers or cements as in the conventional techniques.

Abstract: A method of making a wax pattern by using a dental gypsum model is provided, which comprises the steps of applying a release agent on said gypsum model, coating on the thus applied surface a coating material which leaves no ash upon incinerated at 700.degree. C., and applying a wax melt on said surface. When the wax melt is applied on the gypsum model, the wax is in no direct contact with the release agent, and it is unlikely that gaps may be formed between the wax pattern and the gypsum model or a pad of the wax pattern may warp; that is, the additional operation so far needed for correcting such warpage can be dispensed with, so making precise casting possible. In addition, the presence of the release agent enables removal of the wax pattern to be done as conventional. Furthermore, when the thus removed wax pattern is invested in a investment material to incinerate the wax pattern, no ash of the above coating material remains in the cavity, so that metal can be cast with no defect.