Effect of RSpressing-flask cooling interaction on dental movement in complete denture after storage in water

Abstract

The purpose ofthis study was to investigate the dental movement in maxillary complete dentures after periods of storage in water. Twenty maxillary complete dentures were prepared with the anterior teeth mounted in normal overlapping and the posterior teeth in Angle's class I, n relation to the teeth of the lower stone cast. The final pressing of the flask was made with the RS tension system and the curing cycleprocessed in hot water at 74°C for 9 hours. The deflasking ofthe denture was made after flask cooling in water or in water plus bench storage for 3 hours. The distance measure- ments among I-I (incisive to incisive),PM-PM(pre-molarto pre- molar), M-M(molar to molar), RI- RM (right incisive to right molar) and LI-LM (Ieft incisive to left molar) teeth were made with a STM Olympus linear comparator microscope with precision of 0.0005 mm, after deflasking and periods ofstorage in water of7, 30, and 90 days. The data were submitted to ANOVA and Tukey s test at a significance level of 5%. Except for the LI-LM distance in the 30-day storage period, with the flask cooling in water plus bench storage for 3 hours, there was no statistically significant difference in the other distances, influenced by the types of the denture cooling when the flasks were pressed with aid of the RS tension system.