Effect chemical-mechanical preparation associated with photodynamic therapy in the reduction of microbial loard, LPS, LTA, cytokines pro-inflammatory and substance P in primary endodontic infections

Author(s)

Esdras Gabriel Alves Silva

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2021-02-26

Examining board members

Brenda Paula Figueiredo de Almeida Gomes; Rejane Andrade de Carvalho; Marina Angélica Marciano

• Advisor: Brenda Paula Figueiredo de Almeida Gomes

Abstract

The objectives of this work were: 1) to evaluate the effect of photodynamic therapy on the composition and reduction of the microbiota of teeth with primary infection, by the Checkerboard DNA-DNA Hybridization method; 2) to quantify the levels of LPS, LTA, proinflammatory cytokines IL -1'alfa', TNF-'beta' and substance P. Twenty-four patients in need of endodontic treatment with pulp necrosis and periapical lesion were selected, divided into a conventional group (n = 12) and a PDT group (n = 12). The samples were collected before and after chemomechanical preparation (CMP) and after PDT, using sterile / pyrogenic paper cones. The samples were diluted, plated and incubated to count colony-forming units (CFU / mL). The structure of the microbiota was verified by the Checkerboard. LPS samples were analyzed by the Limulus Amoebocyte Lysate (LAL) and LTA, IL-1'alfa', TNF-'beta' and substance P samples by Enzyme-Linked Immunosorbent Assay (ELISA) method. Regarding microbiological culture, there was bacterial growth in all analyzed samples, compared to the conventional group, CMP was effective in reducing viable bacteria (p <0.05). In the PDT group, there was a significant decrease (p <0.05) in the samples after PDT, in relation to the samples after CMP. Regarding molecular analysis, through the checkerboard, it was observed that bacterial species were found in all initial samples. The most frequent species were Enterococcus hirae and Porphyromonas gingivalis, in mean concentrations of <105 and 106 In the conventional group, after CMP the species presented in concentrations of <105 and 105. In the PDT group, after CMP the average concentrations were <105 and 105, after PDT, the average concentrations were established in <105 and 6 species were not detected. LPS and LTA were detected in all initial samples, represented by means of 20.561 EU / mL and 430.91 pg mL, respectively. CMP significantly decreased (p <0.05) the levels of LPS and LTA, in both groups (p> 0.05). PDT significantly decreased (p <0.05) the levels of LPS and LTA, with statistical difference between groups (p <0.05). IL1-'alfa', TNF-'beta' were produced by macrophages encouraged by the endodontic content, where in the conventional group, CMP significantly decreased (p <0.05) the levels of cytokines, but without difference between groups. In the PDT group, photodynamic therapy progressively decreased cytokine levels with a significant difference (p <0.05) between groups. Regarding substance P, they were quantified in all samples (24/24). In relation to the conventional group, CMP decreased significantly (p <0.05) in relation to the initial group. The PDT was shown to have a greater decrease in the levels of P substance (p <0.05). It was possible to conclude that: 1) Photodynamic therapy proved to be more effective in bacteria by culture and checkerboard, in comparison with the chemical-mechanical preparation; 2) Photodynamic therapy achieved a greater reduction in LPS and LTA levels; 3) Higher levels of reduction of cytokines and substance P were achieved after photodynamic therapy, when compared with those obtained after chemical-mechanical preparation (AU)

• FAPESP's process: 19/09115-1 - Effect of chemomechanical preparation associated with photodynamic therapy in the reduction of microbial, LPS, LTA, substance p and pro-inflammatory cytokines in primary endodontic infection
• Grantee: Esdras Gabriel Alves e Silva
• Support Opportunities: Scholarships in Brazil - Master