Method for making a machinable block of polyurethane elastomer for use in fabricating dental appliances

Abstract

A method of making a machinable puck of a hard, solvent free, substantially non-hydrophilic polyurethane elastomer for use in fabricating dental appliances. The elastomer has a hardness of not less than about Shore D65. A first polyester or polyether polyol with a functionality greater than two and a molecular weight greater than one hundred is reacted with an isocyanate prepolymer prepared from one or more branched polyester or polyether polyols with a functionality greater than two; and then blending prepolymer and first polyester or polyether polyol with nanoparticles and colorants as needed. In one embodiment, the polypropylene glycol triether and the isocyanate prepolymer comprises dicyclohexylmethane 4,4′-diisocyanate. The machined, elastomer appliance is able to be heated in hot water to make it flexible and formable for individual, customed-fitting for the patient.

Dependencies are inferred from the claim text.