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Introduction Poly(methyl methacrylate) is widely used as denture base material due its better physical properties, ease to fabricate, and repair. Despite being the material of choice for the denture fabrication, dentures made from poly(methyl methacrylate) may exhibit dimensional changes due to volumetric shrinkage. This further affects the retention of the denture. Various methods have been used to overcome this problem. One such method is the use of injection molding technique. So, a study was planned to evaluate the efficacy of dentures processed by injection molding technique in reducing the volumetric shrinkage. Objective To evaluate and compare the dimensional accuracy of poly(methyl methacrylate) resin processed by conventional and injection molding technique. Materials and Methods A total of 90 samples were made. Half of the samples (45) were fabricated by compression molding and half (45) by injection molding technique. Dimensional change was studied at three equidistant points in posterior region with the help of digitized travelling microscope. Statistical analysis was done using student’s t-test. Result Dimensional accuracy of injection molded poly(methyl methacrylate) resin was greater than that of compression molded poly(methyl methacrylate).

Aim: All the restorative material whatsoever introduced till-date have an inherent disadvantage of micro-leakage measurable different grades. The present study comparatively evaluates the micro-leakage of glass ionomer restoration with different surface protection methods. Methodology: 36 premolars were obtained without any cracks or restorations for the study. Teeth were stored in distilled water containing thymol crystals till the beginning of the study. The teeth were randomly divided into 3 groups based on surface protectors used. Group I is GC Fuji Varnish, Group II is vaseline and Group III is G-Coat plus along with GIC restoration. Class V cavities were prepared of dimensions mesio-distal width of 3 mm, occluso-gingival length of 2 mm, and a depth of 1.5 mm on buccal and lingual surfaces with a high-speed hand-piece with air-water spray. Results: Kruskal- Wallis test was applied and Vaseline group showed significantly less micro-leakage compared to G-Coat plus i.e. G-Coat plus exhibited significantly higher microleakage compared to other groups. Conclusion: Evaluation of micro-leakage of glass ionomer cements using various surface protecting agents, Vaseline was considered the best surface protecting agent maintaining the water balance and showing no micro-leakage.