Author/Authors :
Gharechahi, Jafar Department of Prosthodontics - School of Dentistry, Mashhad University of Medical Sciences, Mashhad , Asadzadeh, Nafiseh Department of Prosthodontics - Dental Research Center - School of Dentistry, Mashhad University of Medical Sciences, Mash- had , Shahabian, Foad Department of Prosthodontics - Dental Research Center - School of Dentistry, Ahvaz University of Medical Sciences, Ahvaz , Gharechahi, Maryam Department of Endodontics - School of Dentistry, Mashhad University of Medical Sciences, Mashhad
Abstract :
Objective: Acrylic resin denture bases undergo dimensional changes during polymer tion. Injection molding techniques are reported to reduce these changes and thereby prove physical properties of denture bases. The aim of this study was to compare dim sional changes of specimens processed by conventional and injection-molding te niques.
Materials and Methods: SR-Ivocap Triplex Hot resin was used for conventional p sure-packed and SR-Ivocap High Impact was used for injection-molding techniques. ter processing, all the specimens were stored in distilled water at room temperature u measured. For dimensional accuracy evaluation, measurements were recorded at 24-h 48-hour and 12-day intervals using a digital caliper with an accuracy of 0.01 mm. Sta tical analysis was carried out by SPSS (SPSS Inc., Chicago, IL, USA) using t-test and peated-measures ANOVA. Statistical significance was defined at P<0.05.
Results: After each water storage period, the acrylic specimens produced by inject exhibited less dimensional changes compared to those produced by the conventio technique. Curing shrinkage was compensated by water sorption with an increase in ter storage time decreasing dimensional changes.
Conclusion: Within the limitations of this study, dimensional changes of acrylic re
specimens were influenced by the molding technique used and SR-Ivocap injection p cedure exhibited higher dimensional accuracy compared to conventional molding.
