Abstract: Improved titanium alloys for dental castings and processes for the preparation thereof, characterized by the incorporation of predetermined small amounts of one or more noble metals, preferably ruthenium, or rhenium, and optional predetermined small amounts of one or more rare earth metals, preferably cerium. The present alloys have improved corrosion and tarnish resistance under the conditions of use, and the preferred compositions including rare earth metals have improved oxidation resistance which improves their receptivity and bonding strength for enamels, porcelain surfacing materials or caps.

Abstract: The bottom of a solid metal charge melts to fill a form below the charge. During melting, usually, the metal that enters the form remains continuous with an unused solid part of the charge. After cooling, the formed metal is removed together with the unused part of the charge--and usually with the form too. They are separated later or in a different operation, and another charge is positioned immediately for melting into another form, so the useful duty cycle is very high. A preferred form of the invention uses an upper melting chamber and a lower forming chamber, separated by a horizontal wall but communicating by an aperture through the wall. The charge and form are placed against the wall from below to block the aperture. The charge preferably extends up through the aperture into or toward the melting chamber, where an arc electrode or other heater melts the top of the charge, particularly near its center.

Abstract: A light curable pit and fissure sealant composition comprises 2,2-propane-bis [3-(4-phenoxy)-1,2-dihydroxy-propane-1- methacrylate] and triethylene glycol dimethacrylate in a 55:45 weight ratio, a polymerization initiator, titanium dioxide as an opaquing agent, and DEA-EMA of at least 95 percent purity as the polymerization accelerator. Optionally, up to 50% filler can be used.