Effect of sodium trimetaphosphate, associated or not to fluoride, on biomass and fluid of mixed biofilm containing Streptococcus mutans e Candida albicans

Author(s)

Thamires Priscila Cavazana

• Document type: Master's Dissertation
• Press: Araçatuba. 0000-00-00.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba
• Defense date: 2018-01-26
• Advisor: Alberto Carlos Botazzo Delbem; Juliano Pelim Pessan; Douglas Roberto Monteiro

Abstract

The aim of the present study was to verify the effect of sodium trimetaphosphate (TMP), associated or not to fluoride (F), on cultivable cells, total biomass, metabolic activity and composition of the extracellular matrix of mixed biofilms of S. mutans and C. albicans, as well as on the concentrations of F, calcium (Ca) and phosphorus (P) (total biofilm and biofilm fluid) and pH of these biofilms formed in vitro. For both studies, the biofilms were formed in wells of microtiter plates by placing a suspension (1 x 107 cells/mL C. albicans + 1x108 cells/mL S. mutans) in artificial saliva supplemented with sucrose (0,4%), which had half of its content renewed every 24 hours. Biofilms were treated three times (72, 78 and 96 hours of formation), for one minute, with solutions containing TMP (0.25, 0.5 or 1%) with or without 500 ppm F, as well as solutions containing 500 and 1100 ppm F, adopted as positive controls. Artificial saliva was used as treatment and considered as the negative control. For the microbiological study, the following tests were performed: quantification of cultivable cells (CFU), total biomass (colorimetric crystal violet test - CV), metabolic activity (XTT reduction) and quantification of matrix components (protein, carbohydrate and DNA). All assays were performed in triplicate on three different occasions. The results were submitted to one-way analysis of variance, followed by the Fisher LSD‟s test (p<0.05). TMP showed a reducing effect mainly on the metabolism and components of the extracellular matrix of the biofilm. For the study of the concentrations of F, Ca, and P, these ions were analyzed in the total biofilm and in the biofilm fluid after treatment with the test solutions and after the pH measurement of the biofilm. In another set of experiments, after the third treatment (96 h of biofilm formation), the biofilms were exposed for 3 minutes to a 20% sucrose solution. This was removed and after 1 minute the biofilms were collected, and the pH of the medium and F, Ca, and P concentrations were determined both in the biomass and in the biofilm fluid. The data were submitted by two-way analysis of variance, followed by Fisher LSD's test (p<0.05). Treatment with TMP increased F and P concentration of the biofilm fluid, and maintained the pH of the medium close to neutral values even after exposure of the biofilm to sucrose. Thus, it is possible to conclude that TMP interferes with the metabolism, organic and inorganic composition and the pH of the biofilm tested. (AU)

• FAPESP's process: 16/01752-4 - Effect of sodium trimetaphosphate, associated or not with fluoride, in the total biofilm and biofilm fluid formed in vitro
• Grantee: Thamires Priscila Cavazana
• Support Opportunities: Scholarships in Brazil - Master