EFFECTS OF DISINFECTING IRREVERSIBLE HYDROCOLLOID IMPRESSIONS ON THE RESULTANT GYPSUM CASTS - .2. DIMENSIONAL CHANGES

This study evaluated the effect of disinfection time (10, 30, and 60 m inutes) on the dimensional changes of stone casts poured against an ir reversible hydrocolloid impression material (Jeltrate). Impressions we re made of a stainless steel analog of a maxillary arch. The impressio ns were sprayed with bleach, iodophor, phenol, and water and were stor ed for designated times before poured in a type IV stone (Vel-mix). Th e arch width, length, and depth of the vault of the resultant casts we re measured by use of a contact measuring device (MicroVal) capable of measuring to 0.001 mm. Data were analyzed with two-way analysis of va riance at the 95% confidence level. Results indicated that disinfectio n treatment of alginate impressions with surface disinfectants did not cause significant dimensional changes in the resultant stone casts fr om statistical and clinical points of view.