Production and characterization of enamel caries lesion similar to ICDAS II criteria by Streptococcus mutans biofilm

Author(s)

Micaela Cardoso

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2014-05-15

Examining board members

Regina Maria Puppin Rontani; Lidiany Karla Azevedo Rodrigues; Giselle Maria Marchi

• Advisor: Regina Maria Puppin Rontani

Abstract

This study was developed in order to identify the effect of demineralization process to provide bovine enamel caries-like lesions, using Streptococcus mutans biofilms with clinical features similar to those found in ICDAS II (2009) criteria, codes 1, 2 and 3 by visual inspection; to identify the time required for providing the demineralization; to characterize the lesions obtained from different analysis methodologies: X-ray microtomography (?-CT), Scanning Electron Microscopy (SEM), Transversal Microradiography (TMR) and light polarized optical microscopy (MLP). It was used 45 enamel block divided into 3 groups (n =15) submitted to caries-like lesions by biological method, with Streptococcus mutans biofilm. The specimens were immersed in BHI broth supplemented with 1% sucrose inoculum of S. mutans and the medium was changed every 24 hours. Then, the specimens were removed from the culture media in each period of time (24h, 4 and 14 days) and pictures were taken from their demineralized surface (visual analysis). Next, the specimens were submitted to ?-CT and SEM evaluations and longitudinally sectioned by the caries lesions and they were evaluated in TMR e MLP. Data obtained from SEM were descriptively evaluated. Data from ?-CT, TMR and MLP were submitted to ANOVA and Tukey's tests (p<0,05). The time required to produce clinical lesions similar to those ICDAS II for each protocol code was visually identified. For the production of lesions in vitro similar to code 1, the time required was 24 hours, code 2 for 4 days and code 3 for 14. For the similar lesion to those from code 1, the MLP and TMR identified the presence of subsurface carious lesions, but ??CT did not allow viewing it. The SEM analysis showed smoother surface, mostly without signs of erosion and pinholes caused by S mutans. For code 2 lesions the ??CT analysis identified lesions areas and volume smaller than Code 3. The lesion depth cannot be identified by ??CT for both codes. MLP and TMR identified higher depths to code 3 as compared to 2, however, showed the presence of demineralization and cavitation also higher than code 3 ICDAS. The lesion depth average from the three groups was measured by TMR and MLP methods, and both analyses showed that the higher the ICDAS II code, the deeper the lesions were. Different methods may be employed in accordance with the recommended type of lesion produced artificially (AU)

• FAPESP's process: 11/15973-9 - Evaluation of enamel caries-like lesions produced by a S. mutans biofilm
• Grantee: Micaela Cardoso
• Support Opportunities: Scholarships in Brazil - Master