Proinflammatory Activity of Primarily Infected Endodontic Content against Macrophages after Different Phases of the Root Canal Therapy

Author(s)

Marinho, Ariane C. S. ^[1] ; Martinho, Frederic C. ^[1] ; Leite, Fabio R. M. ^[2] ; Nascimento, Gustavo G. ^[3] ; Gomes, Brenda P. F. A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, UNICAMP, Endodont Div, Dept Restorat Dent, Sao Paulo - Brazil

^[2] Fed Univ Pelotas UFPel, Pelotas Sch Dent, Dept Semiol & Clin, Periodont Div, Pelotas - Brazil

^[3] Fed Univ Pelotas UFPel, Pelotas Sch Dent, Grad Program Dent, Pelotas - Brazil

• Document type: Journal article
• Source: JOURNAL OF ENDODONTICS; v. 41, n. 6, p. 817-823, JUN 2015.
• Web of Science Citations: 5

Abstract

Introduction: This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin {[}IL]-1 beta and tumor necrosis factor {[}TNF]-alpha) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Methods: Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca{[}OH](2) + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1 beta/TNF-alpha measurement using enzyme-linked immunosorbent assay. Results: Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1 beta and TNF-alpha were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1 beta and TNF-alpha release decreased proportionally to the levels of residual endotoxin (P < .05). Conclusions: Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages (AU)

• 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
• FAPESP's process: 13/02402-9 - Microbiological and LPS investigation and their antigenic activity in teeth with pulpal necrosis and irreversible pulpitis in pro-inflammatory cytokine production
• Grantee: Ariane Cássia Salustiano Marinho
• Support Opportunities: Scholarships in Brazil - Doctorate
• 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