Disinfection of dental gypsum model with 0.5% sodium hypochlorite: Effect on dimensional stability

Objective: to evaluate and compare the effect different techniques of disinfection of irreversible hydrocolloid and type iii dental gypsum,with 0.5% naocl,on their (linear) dimensional stability. study design: quasi experimental study. setting: department of metallurgy,pakistan council for scientific and industrial research (pcsir) lahore. duration with dates: six months,from june 1,2006 to november 30,2006. subjects and methods: ninety (90) casts were made from irreversible hydrocolloid impression by non-probability purposive sampling technique. measurements of the casts at three specific points were carried out using measurement guiding template through screw gauge and were recorded. results: in this study sodium hypochloride 0.5% was used as disinfectant material for type iii dental gypsum. disinfection of type iii dental gypsum,by sodium hypochloride 0.5% had no negative effect on their linear dimensional stability. conclusion: disinfection of dental gypsum type-iii either by immersion and incorporation is easy and dimensionally stable.