Heat cure acrylic resin is the most widely used material for the fabrication of removable dentures even today. But due to its low fatigue strength and fracture resistance, the dentures tend to flex and can also fracture. With the advancement in nanoscience, nano-sized fillers were found to exhibit improved fracture resistance. Hence in this study both ZrO 2 (5%) & TiO 2 (1%) nanoparticles and its hybrid combination (2%) were used to comparatively evaluate the impact and flexural strengths of high impact acrylic resin. A total of 45 specimens were subjected to impact strength testing in an impact tester and flexural strength testing using three point bending test in a Universal testing machine respectively. The present study shows that hybrid reinforcement can be considered a better reinforcement option for enhancing the impact and flexural strengths of acrylic resin.

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Aim:The aim of this study was to evaluate and compare flexural strength of repaired heat polymerized acrylic resin with zirconia oxide and aluminium oxide nanoparticles incorporated autopolymerized acrylic resin and to evaluate effect of butt and bevel joint design of repair with and without chemical surface treatment. Materials and Method: A total of 165 heat cure acrylic resin specimens were fabricated and divided into 3 main groups. Group A had 15 intact specimens whereas group B and group C were further divided into 5 subgroups depending on repair material, repair design and chemical surface treatment used. Each subgroup had 15 specimens. 7wt% zirconia oxide and 2wt% aluminium oxide nanoparticles used as reinforcement material into autopolymerized acrylic resin and compared with unreinforced autopolymerized resin used for repair. Butt and bevel joint designs and ethyl acetate as a chemical surface treatment used for repair of acrylic specimens. The specimens were subjected to flexural strength in a universal testing machine until specimens fractured and load values were recorded. Flexural strength wascalculated in MPa (Megapascal) and analysed using Independent t test, One Way ANOVA and Post hoc Tukey's test. Results: The flexural strength values obtained were highly significant for nanoparticles reinforced groups than unreinforced autopolymerized resin. Also zirconia oxide nanoparticles showed higher values than aluminium oxide nanoparticles. Similarly, repair with bevel joint design and with chemical surface treatment with ethyl acetate proved to be better. Conclusion:Under the conditions of this study, 7wt% zirconia oxide and 2wt% aluminium oxide reinforced autopolymerized resin with bevel joint design and chemical surface treatment with ethyl acetate can be recommended for acrylic repair.

In the existing practice of xed prosthodontics, certain situations like pier abutments, tilted abutments create problems with rigid connectors. If rigid connectors are used in this situation, the pier abutment will act as a fulcrum because of physiologic tooth movement, arch position of the abutment, and the retentive capacity of the retainers. A nonrigid connector may be preferred in construction of xed partial denture (FPD) with pier abutment. In this prosthesis, the movement of the nonrigid connector is enough to prevent the pier abutment from serving as a fulcrum. This clinical report describes rehabilitation of a patient with FPD with pier abutment using semi-precision attachment. The technique used is simple, economical, and feasible in a simple laboratory set up.

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