title: Study of resin-bonded calcia investment: Part 1. Setting time and compressive strength.
abstract: This study was carried out to develop a new titanium casting investment consisting of calcia as the refractory material and a cold-curing resin system as the binder. The setting time of the investment was investigated under different N,N-dimethyl-p-toluidine (DMPT) contents in methyl methacrylate monomer (MMA) and benzoyl peroxide (BPO) contents in calcia without any sintering agent. The effects of the sintering agents, which were calcium fluoride (CaF2) and calcium chloride (CaCl2), on the compressive strength of the investments were investigated at room temperature before and after heating to two different temperatures. The shortest setting time (68 minutes) of the investment was obtained at 0.37 DMPT/BPO (1.5 vol% /1.0 mass%) ratio by mass. The highest strength (16.5 MPa) was obtained from the investment which contained 2 mass% CaF2 and was heated to 1,100 degrees C. It was found that the developed calcia investment containing 2 mass% CaF2 has a possibility for use in titanium castings.
authors.affiliation: Department of Dental Materials Science, School of Dentistry at Niigata, The Nippon Dental University, 1-8 Hamaura-cho, Niigata, Niigata 951-8580, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Nakai
mesh_terms: D000497:Alloys; D000704:Analysis of Variance; D001585:Benzoyl Peroxide / Q000737:chemistry; D002122:Calcium Chloride / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D002124:Calcium Fluoride / Q000737:chemistry; D019245:Compressive Strength; D003734:Dental Casting Investment / Q000737:chemistry*; D003735:Dental Casting Technique; D006358:Hot Temperature; D008422:Materials Testing; D020366:Methylmethacrylate / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D018709:Statistics, Nonparametric; D013674:Technology, Dental; D013997:Time Factors; D014025:Titanium; D014052:Toluidines / Q000737:chemistry
chemical_list: D000497:Alloys; D017610:Calcium Compounds; D003734:Dental Casting Investment; D010087:Oxides; D014052:Toluidines; C031462:titanium alloy (TiAl6V4); D020366:Methylmethacrylate; C016538:lime; D014025:Titanium; D002122:Calcium Chloride; D002124:Calcium Fluoride; C015835:dimethyl-4-toluidine; D001585:Benzoyl Peroxide