Quantification of cultivable bacteria and endotoxin in post-treatment apical periodontitis before and after chemo-mechanical preparation

Author(s)

Endo, M. S. ^[1] ; Martinho, F. C. ^[1] ; Zaia, A. A. ^[1] ; Ferraz, C. C. R. ^[1] ; Almeida, J. F. A. ^[1] ; Gomes, B. P. F. A. ^{[2, 1]}

Affiliation

^[1] State Univ Campinas UNICAMP, Piracicaba Dent Sch, Dept Restorat Dent, Endodont Div, Piracicaba, SP - Brazil

^[2] State Univ Campinas UNICAMP, Area Endodontia, Fac Odontol Piracicaba, BR-13414018 Piracicaba, SP - Brazil

• Document type: Journal article
• Source: EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES; v. 31, n. 10, p. 2575-2583, OCT 2012.
• Web of Science Citations: 14

Abstract

This clinical study was conducted to quantify cultivable bacteria and endotoxin in root canals with post-treatment apical periodontitis by correlating their levels with clinical features and to evaluate the effect of chemo-mechanical preparation (CMP) with 2 % chlorhexidine gel + 17 % EDTA on bacterial and endotoxin removal/elimination. Moreover, target strict Gram-negative anaerobic bacteria were investigated by polymerase chain reaction (PCR). Fifteen teeth with post-treatment apical periodontitis were sampled before (s1) and after (s2) CMP. Culture techniques determined the number of colony-forming units (CFU). PCR (16S rDNA) and limulus amebocyte lysate (LAL) assay were used for bacterial and endotoxin detection, respectively. Prevotella nigrescens (4/15), Prevotella intermedia (2/15), and Tannerella forsythia (2/15) were the most frequently detected species. Endotoxin was recovered in 100 % of the samples. At s1, bacteria and endotoxin were detected at a median value of 5.14 x 10(3) CFU/mL and 3.96 EU/mL, respectively. Higher levels of endotoxin were related to a larger size of radiolucent area (> 5 mm) (p < 0.05). CMP was more effective in reducing bacteria (99.61 %) than endotoxin (60.6 %) (both p < 0.05). Our findings indicated that the levels of endotoxin found in infected root canals were related to a larger size of radiolucent area in the periapical region. Moreover, CMP was effective in reducing both bacterial and endotoxin contents in post-treatment apical periodontitis. (AU)

• FAPESP's process: 10/17877-4 - Microbiological analysis and quantification of endotoxins and proinflammatory cytokines from primarily infected root canals with apical periodontitis
• Grantee: Brenda Paula Figueiredo de Almeida Gomes
• Support Opportunities: Regular Research Grants
• FAPESP's process: 10/19136-1 - Microbiological and endotoxins analysis in primarily infected root canals with apical periodontitis and their antigenic potencial against macrophages to produce IL1-beta e TNF-alfa during endodontic treatment
• Grantee: Brenda Paula Figueiredo de Almeida Gomes
• Support Opportunities: Regular Research Grants