Comparison of a national silicone with potential use for the manufacture of maxillofacial prostheses with a commercial silicone against 3 hygiene protocols

• Grant number: 20/13220-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2021
• End date: December 31, 2021
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Cláudia Helena Lovato da Silva
• Grantee: Priscilla Lai Liu
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The objective of this study is to compare two silicones for maxillofacial prosthesis, after exposure to 3 hygiene protocols. For color, hardness and roughness analysis, 15 specimens (N = 270; 12 mm Ø x 3 mm) will be distributed in groups, according to 2 materials (A2000; specific and 2420; national) x 3 hygiene protocols [ cleansing with neutral soap (control); cleansing with neutral soap and immersion in 0.15% triclosan; cleansing with neutral soap and immersion in 2% hydrogen peroxide] x 3 pigments [colorless (control), intrinsic, intrinsic + extrinsic]. The variables will be measured after obtaining the specimens (T0) and after using the protocols for 6 months (T6). The color will be evaluated with a portable spectropolarimeter and the standard color system Standart Commission Internationale by L Eclairage (CIE LAB); Shore A hardness will be evaluated with Shore A durometer with the specimens positioned under another specimen of 3 mm (6 mm) and a constant force of 1 kg for 5 seconds. The surface roughness will be analyzed with a digital roughness meter. Mixed biofilm composed of Streptococcus aureus, Pseudomonas aeruginosa, Enterococcos faecallis, Candida glabrata, Escherichia coli and Streptococcos mutans will be formed on 12 specimens (N = 216; 12 mm Ø x 3 mm), for each material / disinfection protocol / combination pigmentation and exposed to hygiene protocols; the microbial load will be given by counting colony-forming units. The data will be analyzed for normality (Shapiro-Wilk test) and homoscedasticity (Levene test) to define the statistical tests to be used with ±<0.05 and aided by SPSS 21.0 software (SPSS Inc, Chicago, Ill, USA).