Methods: The Soft lining materials were mounted on the prepared disc form (14 mm x 2 mm) acrylic resin base (meliodent, Heraeus Kulzer,Germany), n = 75. Five specimens from the three soft liners were immersed in each denture cleanser and one disinfectant for 8 hours; this represented the normal overnight cleansing regime. Fresh solutions of denture cleanser and disinfectant were prepared each day and following the immersion period, the specimens were stored in tap water at 37ºC for the remainder of 24-hour period (24 -8 = 16hrs). This procedure was repeated for 60 days with the interval of 3,7,14, 28 and 60 days. The Control specimens were stored in tap water at 37ºC. Sorption was expressed as a percent of weight loss or gain compared with the weight of the initial sample by using digital electronic balance (sartorius, Germany).
Results: The GLM Repeated Measures procedure was conducted to test the null hypotheses about the effects of both the subjects factors and the within factors. The results of the analysis indicated that there is a significant effect (P < 0.05) in terms of weight gain for immersion period and there is a significant interaction effect for immersion period-by-material and immersion period-by-denture cleanser.
Conclusion: significant weight gain with longer immersion period but the amount of weight gain is dependent on type of material and denture cleanser.
This study was supported by IPPP-P0210/2007A; University of Malaya, Kuala Lumpur, Malaysia