Surface texture and some properties of acrylic resins submitted to chemical polishing

Abstract

The effects of chemical polishing on dental acrylic resin properties are not well clarified. This study evaluated the effect of chemical and mechanical polishing on the residual monomer release (RM), Knoop hardness (KH), transverse strength (TS) and surface texture (ST) of a heat- and self-cured acrylic resin. Four groups were formed: GI-self-cured resin/mechanical polishing; GII-self-cured resin/chemical polishing; GIII-heat-cured resin/mechanical polishing; GIV-heat-cured resin/chemical polishing. Following the polishing procedures, specimens were stored in distilled water at 37 degrees C. The KH and RM measurements were taken after 1, 2, 8 and 32 days of storage, and TS after 2, 8 and 32 days. Surface texture was observed under SEM evaluation. Results were compared statistically at a confidence level of 95%. The following conclusions were drawn: (1) regardless of the acrylic resin and the period of analysis, chemical polishing increased RM levels, reduced KH, and did not affect TS significantly; (2) water storage increased the surface hardness of GII and GIV; (3) GII and GIV showed a smooth and wavy surface under SEM evaluation.

Effect of different disinfectants on the microhardness and roughness of acrylic resins for ocular prosthesis

“…The water absorption can affect the resistance of the polymer, acting as a plasticiser, which decreases the mechanical properties of the material 14,15,35 by reducing the forces between the polymer chains. Therefore, water molecules penetrate into the polymethylmethacrylate and promote separation of the polymer chains and a slight Some authors showed the effect of monomer release and additional polymerisation on the mechanical properties of acrylic resins after long period of water storage 37,38 . The polymethylmethacrylate tends to absorb water in its inhibition process, so that their crystal structures process a high internal energy 36 .…”

Effectiveness of disinfectants on the adherence of <i>Candida albicans</i> to denture base resins with different surface textures

“…On the other hand, chemical solutions may also have undesirable effects such as changes in color of dentures, increased roughness, and reduction in hardness of the denture acrylic resin surface (20,21). Furthermore, immersion of dentures in chemical solutions may lead to absorption of these liquids by the acrylic resin, which can then be released into the oral cavity (22) and leave an unpleasant residual taste (23).…”

Comparative effects of denture cleansers on physical properties of polyamide and polymethyl methacrylate base polymers

“…However, the present concern about these materials is that there is insufficient scientific evidence regarding the properties of the high-impact acrylics and polyamide resins due to the small number of studies comparing the PMMA-based resins 18,19) .…”