IN VITRO STUDY ON MARGINAL MICROLEAKAGE OF FOUR TEMPORARY CEMENTS IN PROVISIONAL CROWNS
Background: Prolonged retention of provisional restoration is depends upon the long term affinity between restoration and teeth structures which depend upon the use of good mechanical characteristics, low solubility, and superior adhesion quality of luting cement which also resist bacterial and molecular penetration. Hence, assessment of marginal leakage of provisional restorative materials sealed with provisional cements using the standardized procedures is essential. Aim: This study aimed at in vitro study of microleakage of 4 provisional cements, a cavity base compound and a zinc-phosphate luting cement in provisional acrylic resin crowns fixed on extracted human teeth. Material & Methods: The teeth with acrylic restorations were randomly divided into 6 groups of 6 specimens each. Each group received different types of temporary cement. Acrylic resin crowns were made and fitted on intact human premolars with the 4 cements. All restorations were applied in a standardized manner. Specimen were submerged in a 2% methylene blue solution, then sectioned and observed under a stereomicroscope for the detection of marginal microleakage. Obtained data were subjected to ANNOVA and Chi –square test to know statistical significant difference between different groups. P value less than 0.05 was considered significant. Results and observation: Mean frequency of microleakage was statistically significant among all the groups under study with Pvalue<0.017. Conclusion: Among all the temporary cement, Zinc-phosphate cements has the best property with reduced microleakage. Even it is used as cavity base but can be used as good temporary cement as far as microleakage is concerned. Key words, Microleakage, provisional cement, restorations, crowns, in vitro