Abstract: A system and method is disclosed for obtaining precisely registered, articulated castings of upper and lower dental impressions. The dental impressions are obtained through use of a dental tray having a non-porous, bite-deformable central septum. The impression material for the upper dental impression is contained in the upper portion of the tray. The impression material for the lower dental impression is contained in the lower portion of the tray and is supported by a bottom cover which is removed subsequent to placement of the tray in the mouth. As the patient bites, the impression material in the upper and lower portions of the dental tray is molded to the contour of the teeth and gums in their proper relationship with the teeth closed. After the material has set, the tray containing registered upper and lower impressions is removed from the mouth and placed into a mold.

Abstract: A process for the addition of Si-bonded hydrogen to an aliphatic multiple bond in the presence of a platinum catalyst selected from the group consisting of______________________________________ I XPtY, II ##STR1## III APt(Y')X"and ______________________________________mixtures thereof, in which A is a halogen, X is a substituted or unsubstituted hydrocarbon radical having from 1 to 3 aliphatic double bonds which is bonded to the platinum atom via a PtC-sigma bond and a Pt-olefin-Pi-bond, X' is a hydrocarbon radical which is substituted with an alkoxy or acyloxy group and has from 1 to 3 double bonds and is bonded to the platinum atom via a PtC-sigma bond and a Pt-olefin-Pi-bond, X" is a substituted or unsubstituted hydrocarbon having an aliphatic double bond which is bonded to the platinum atom via a Pt-olefin-Pi-bond, Y is a chelate-like bonded beta-diketonate ligand or arylcarboxylate ligand, Y' is a beta-diketonate ligand and Z is a double link bridge ligand.

Abstract: Method and apparatus for preparing a wax replica of a dental prosthesis is disclosed. The method of the invention is carried out by preparing a composite dental model which includes a base portion, an odontal die projecting from the base portion having a cavity in which the dental prosthesis is to be implanted, and an index pin embedded within the composite dental model. A complementary dental model having an odontal projection defining an occlusal surface for engaging the odontal die is also prepared. The index pin includes an anchor shank portion embedded within the odontal die, an alignment shank portion embedded in the base portion and a radially projecting collar portion disposed in the interface of the base portion and the odontal die. The odontal die and embedded index pin are removed from the base portion of the composite dental model and a die spacer is placed around the alignment shank portion of the index pin.

Abstract: A system and method is disclosed for obtaining precisely registered, articulated castings of upper and lower dental impressions. The dental impressions are obtained through use of a dental tray having a non-porous bite-deformable central septum. The impression material for the upper dental impression is contained in the upper portion of the tray. The impression material for the lower dental impression is contained in the lower portion of the tray and is supported by a bottom cover which is removed subsequent to placement of the tray in the mouth. As the patient bites, the impression material in the upper and lower portions of the dental tray is molded to the contour of the teeth and gums in their proper relationship with the teeth closed. After the material has set, the tray containing registered upper and lower impressions is removed from the mouth and placed into a mold.

Abstract: A method for forming a layered dental restoration in which there is a continuous polymeric resin phase but in which the reinforcing filler compositions of the respective layers are different. A sub-layer, composed of a polymeric resin binder having a refractive index within the range of about 1.53 to 1.56, in admixture with suitable catalysts and a finely-divided reinforcing inorganic filler having a refractive index substantially different than that of such resin, is first applied to the site of restoration and, before the sub-layer has fully cured, a surface layer composed of the same resin and catalysts but a different inorganic filler is applied to the site over the sub-layer. The filler of the surface layer consists essentially of a finely-divided inorganic material having substantially the same refractive index as that of the resin common to both layers.

Abstract: A blend of powders suitable for use in powder/liquid moulding applications comprising a high molecular weight polymer powder of methyl methacrylate and a methyl methacrylate copolymer powder containing more than 7% but less than 15% by weight of 2-ethyl hexyl acrylate, both powders having defined particle sizes.

Abstract: An athletic mouthguard for use by participants in contact sports to simultaneously protect and topically treat the teeth. The mouthguard is a generally U-shaped channel molded preferably from a composition of thermoplastic resin and a fluoride compound such as sodium fluoride, stannous fluoride, or sodium fluorosilicate. The fluoride compound is released from the molded resin mouthguard to the wearer's teeth over extended periods of use.

Abstract: The invention relates to a method for preparing a dental impression which comprises applying a dental impression material to a tooth of which an impression is to be taken, curing the material and thereafter removing the resulting impression from the tooth, said dental impression material being a mixture ofA. a diorganopolysiloxane containing terminal triorganosiloxy groups in which at least one vinyl group is present in each of the triorganosiloxy groups,B. an organopolysiloxane having at least three Si-bonded hydrogen atoms per molecule,C. a catalyst capable of promoting the addition of Si-bonded hydrogen to vinyl groups at room temperature and, if desired,D. additives such as fillers, pigments, flavoring substances and plasticizers.

Abstract: A female attachment for a dental prosthetic device is made by embedding the precision male part of a precision core into a wax-up, leaving the anchor part thereof exposed; sculpting the wax at the boundary line between said precision male part and said anchor part; investing the wax-up and core with investment material; removing the wax, leaving the core and the investment material to form a mold cavity; casting the prosthetic part in the mold cavity to form a female attachment in the resulting prosthetic device; and thereafter removing the core and the investment material.

Abstract: A process for forming a removable dental cast embedded with a plastic, threaded, cast ejector button, and apparatus for fabricating a plurality of cast ejector buttons comprised of a mold device including an upper plate containing a plurality of mold cavities, and a base plate incorporating coil spring means for resiliently maintaining the upper plate in a predetermined spaced-apart and open relation thereto and a plurality of rigid support elements attached, at their bottom ends, in vertically-upright relation on the base plate and slidably engaged, at their upper ends, in a bottom opening in each upper plate-mold cavity and extending in overlapping relation into the respective cavity. The upper ends of each rigid support element are threaded so that, when the mold cavities are poured with and filled by a suitable material, in the plastic flow form that is allowed to set for a specified period, a separate and internally threaded plastic cast ejector button is formed in each cavity.