IRREVERSIBLE HYDROCOLLOID AND GYPSUM INTERACTIONS

This study examined the compatibility of nine popular gypsum products with three more recently developed irreversible hydrocolloid impressio n materials, some of which were disinfected before pouring. A test die and evaluation procedure conforming to ANSI/ADA specification no. 18 standards were used to evaluate detail reproduction of the impression materials and detail transfer and roughness of the resultant die. Stat istical evaluation of the data revealed that there continue to be dele terious surface interactions between specific irreversible hydrocolloi d materials and gypsum products. Analysis also confirmed that the phen olic disinfectant used in this study did not influence the surface int eraction between materials nor alter the resultant dimensional propert ies of the gypsums used.