Shelf Life of Sterilized Rolls Used in Dental Practice.

Abstract

The aim of this study was to examine the shelf life of sterilized rolls used in dental practice. The experimental study was designed by 1200 sample packs, made of sealed roles, each containing a small piece of paper 0.5 mm. in diameter simulated dental instrument, were prepared and steam sterilized. The sample rolls were grouped into 4 types, the new and the reused, 1,2 and 3 times. After sterilization, the 4 groups of sample packs were placed, exposed to environment, in dental clinic. The paper in each roll, 10 packs per group, were daily analysed for bacterial contamination in 30 days. The recorded data were positive or negative. It was found positive in the group of new roll on the 14th. day of experiment while the reused group were found on the 13th., 3rd. and 5th. day for the first, second and third reused group respectively. By means of the statistical t-test showed the mean contaminated roll of the new one was significantly different from the reused (p < 0.05). The cumulative number of contaminated rolls in reused groups were higher than the new one and showed by graph that the new rolls were efficiently non-contaminated.