OBJECTIVE To evaluate the surface roughness of acrylic resin submitted to chemical disinfection via 1% sodium hypochlorite (NaClO) or 1% peracetic acid (C2H4O3). MATERIALS AND METHODS The disc-shaped resin specimens (30 mm diameter ×4 mm height) were polymerized by heated water using two cycles (short cycle: 1 h at 74°C and 30 min at 100°C; conventional long cycle: 9 h at 74°C). The release o...

The association between a toothbrush and a dentifrice is the most used denture cleaning method. The purpose of this study was to evaluate the abrasiveness of specific and non-specific denture cleaning dentifrices on different heat-polymerized acrylic resins. Sixteen specimens (90 x 30 x 3 mm) of each acrylic resin (QC-20, Lucitone 550, Clássico, Vipi-Cril) were prepared and randomly assigned to...

STATEMENT OF PROBLEM Hard denture acrylic resins must maintain color stability to remain esthetic. PURPOSE The purpose of this in vitro study was to measure the color stability of denture resins subjected to staining agents and cleaned with denture cleansers MATERIAL AND METHODS Forty-five disks (10-mm diameter, 2-mm thick) fabricated from 3 denture resins (light polymerized Eclipse; heat p...

The purpose of this study was to evaluate the shear bond strength of two resin composites around different types of fiber posts. Twenty post specimens were prepared for three types of fiber posts. Posts were embedded in acrylic resin blocks with half of the post diameter exposed. The exposed portions of the posts were successively ground with silicon carbide paper until flattened flush with the...

OBJECTIVE To evaluate the effect of disinfectants and distilled water on the micro-hardness of heat cure acrylic resins. METHODS The case-control study was conducted at Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, and Nadirshaw Edulji Dinshaw University of Engineering and Technology, Karachi, from April to October 2011. Specimens were fabricate...

Purpose: The mechanical strength of polymethyl methacrylate (PMMA) remains far from ideal for maintaining the longevity of denture. The purpose of this study was to evaluate the effect of Zirconium oxide (ZrO2) nanofillers powder with different concentration (1.5%, 3%, 5% and 7%) on the flexural strength, fracture toughness, and hardness of heat-polymerized acrylic resin. Materials and methods:...

The purpose of this study was to assess color alteration of the paints used for iris painting in artificial eyes. Five disks of heat cured acrylic resin were confectioned by microwave energy for each paint analyzed, in a total of 40 specimens. Each specimen consisted of a colorless acrylic resin disk and another of equal size, of scleral white colored acrylic resin, with the painting interposed...