Microbiological and endotoxin contain from primarily infected root canals and periapical abscess and their relation with clinical symptoms, proinflammatory cytokines and P substance levels

• Grant number: 13/23061-5
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: March 01, 2014
• End date: November 30, 2016
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Brenda Paula Figueiredo de Almeida Gomes
• Grantee: Daniel Rodrigo Herrera Morante
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The main virulence factor of gram-negative bacteria is represented by the release of endotoxin (LPS) presented in the outer layers of their cell walls. The accumulation of these bacterial components in the root canal and periradicular tissues should produce an antigen-antibody reaction stimulating an inflammatory response know as apical periodontitis. Thus, the aim of this study is to isolate and identify gram-negative anaerobic species through clonal molecular methods from samples of root canals of teeth with asymptomatic and symptomatic apical periodontitis; quantify endotoxins correlating this content with the expression of pro-inflammatory cytokines, matrix metaloproteinases (MMPs) and P substance. Twenty-four patients needing endodontic intervention by necrosis of the pulp tissue and the presence of apical periodontitis without painful symptoms (n = 12) and patients with painful symptoms and periapical abscess (n = 12) will be select. As control group, will be selected patients needing endodontic treatment by prosthetic indication for teeth with pulp vitality (n = 6). Endotoxin and microbiological samples will be collected before the chemomechanical preparation ( PQM ) , after the PQM , after the use of 17% EDTA and 30 days after the first session . Samples for measurement of IL- 1± , IL- 1² , TNF , PGE -2 , MMP -2 , MMP -3 , MMP -8 , MMP -9 , MMP -13 and P substance also be collected by passing a paper cone 1 mm beyond the root apex after the PQM and after intracanal medication (MIC). The microbiological samples will be diluted, plated and incubated for further isolation and cloning . The samples will be analyzed by LPS Amoebocyte Limulus Lysate (LAL). Samples for measurement of cytokines, MMPs and P substance will be quantified using specific kits for determination in human samples by Enzyme -Linked Immunosorbent Assay (ELISA). The values obtained will be tabulated and statistically analyzed.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

HERRERA, DANIEL RODRIGO; DURAND-RAMIREZ, JORGE ENRIQUE; FALCAO, AMANDA; LEAL NOGUEIRA DA SILVA, EMMANUEL JOAO; DOS SANTOS, ELIZABETE BRASIL; FIGUEIREDO DE ALMEIDA GOMES, BRENDA PAULA. Antimicrobial activity and substantivity of Uncaria tomentosa in infected root canal dentin. BRAZILIAN ORAL RESEARCH, v. 30, n. 1, p. 5-pg., 2016-01-01. (13/23061-5)

HERRERA, DANIEL RODRIGO; DURAND-RAMIREZ, JORGE ENRIQUE; FALCAO, AMANDA; LEAL NOGUEIRA DA SILVA, EMMANUEL JOAO; DOS SANTOS, ELIZABETE BRASIL; FIGUEIREDO DE ALMEIDA GOMES, BRENDA PAULA. Antimicrobial activity and substantivity of Uncaria tomentosa in infected root canal dentin. Brazilian Oral Research, v. 30, n. 1, 2016. (13/23061-5)

HERRERA, D. R.; MARTINHO, F. C.; DE-JESUS-SOARES, A.; ZAIA, A. A.; FERRAZ, C. C. R.; ALMEIDA, J. F. A.; GOMES, B. P. F. A.. Clinical efficacy of EDTA ultrasonic activation in the reduction of endotoxins and cultivable bacteria. International Endodontic Journal, v. 50, n. 10, p. 933-940, OCT 2017. (10/17877-4, 13/23061-5)