Physical Properties of an Acrylic Resin after Incorporation of an Antimicrobial Monomer

Author(s)

Regis, Romulo Rocha ^[1] ; Zanini, Ana Paula ; Della Vecchia, Maria P. ^[1] ; Silva-Lovato, Claudia Helena ^[1] ; Oliveira Paranhos, Helena Freitas ^[1] ; de Souza, Raphael Freitas ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Dent Sch, Dept Dent Mat & Prosthodont, Ribeirao Preto - Brazil

• Document type: Journal article
• Source: JOURNAL OF PROSTHODONTICS-IMPLANT ESTHETIC AND RECONSTRUCTIVE DENTISTRY; v. 20, n. 5, p. 372-379, JUL 2011.
• Web of Science Citations: 15

Abstract

Purpose: This study evaluated the effect of the incorporation of the antimicrobial monomer methacryloyloxyundecylpyridinium bromide (MUPB) on the hardness, roughness, flexural strength, and color stability of a denture base material. Materials and Methods: Ninety-six disk-shaped (14-mm diameter x 4-mm thick) and 30 rectangular (65 x 10 x 3.3 mm(3)) heat-polymerized acrylic resin specimens were divided into three groups according to the concentration of MUPB (w/w): (A) 0%, (B) 0.3%, (C) 0.6%. Hardness was assessed by a hardness tester equipped with a Vickers diamond penetrator. Flexural strength and surface roughness were tested on a universal testing machine and a surface roughness tester, respectively. Color alterations (Delta E) were measured by a portable spectrophotometer after 12 and 36 days of immersion in water, coffee, or wine. Variables were analyzed by ANOVA/Tukey HSD test (alpha = 0.05). Results: The following mean results (+/-SD) were obtained for hardness (A: 15.6 +/- 0.6, B: 14.6 +/- 1.7, C: 14.8 +/- 0.8 VHN; ANOVA: p = 0.061), flexural strength (A: 111 +/- 17, B: 105 +/- 12, C: 88 +/- 12 MPa; ANOVA: p = 0.008), and roughness (A: 0.20 +/- 0.11, B: 0.20 +/- 0.11, C: 0.24 +/- 0.08 mu m; ANOVA: p = 0.829). Color changes of immersed specimens were significantly influenced by solutions and time (A: 9.1 +/- 3.1, B: 14.8 +/- 7.5, C: 13.3 +/- 6.1 Delta E; ANOVA: p < 0.05). Conclusions: The incorporation of MUPB affects the mechanical properties of a denture base acrylic resin; however, the only significant change was observed for flexural strength and may not be critical. Color changes were slightly higher when resin containing MUPB was immersed in wine for a prolonged time; however, the difference has debatable clinical relevance. (AU)

• FAPESP's process: 08/02725-4 - Effect of the incorporation of an antiseptical monomer on color stability of a denture base acrylic resin
• Grantee: Ana Paula Zanini
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 07/05245-0 - Incorporation of an antiseptic monomer in a denture base acrylic resin
• Grantee: Raphael Freitas de Souza
• Support Opportunities: Regular Research Grants