Influence of passive ultrasonic irrigation on bacterial and endotoxin reduction from root canal system: a randomized clinical study

• Grant number: 13/02923-9
• Support type: Regular Research Grants
• Duration: October 01, 2013 - September 30, 2015
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal researcher: Giulio Gavini
• Grantee: Giulio Gavini
• Home Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Assoc. researchers: Ericka Tavares Pinheiro ; Marcia Pinto Alves Mayer ; Vitor Cesar Nakamura

Abstract

Chemomechanical procedures along sodium hypochlorite (NaOCl) irrigation promote a substantial elimination of microorganisms and endotoxins from root canal; however, almost 50% of the canals still harbor bacteria after chemomechanical debridement, as detected by molecular methods. Therefore, supplementary approaches have been proposed to optimize root canal disinfection; including a passive ultrasonic irrigation (PUI). The purpose of this clinical study is to compare the results of 2 irrigation protocols, PUI and standard irrigation, in obtaining bacterial and endotoxin reduction from root canals. A total of 50 patients requiring endodontic therapy of teeth with apical periodontitis will be recruited for the study. The patients will be randomly distributed in 2 groups, according to the irrigation protocol to be used during the therapy: PUI - Passive Ultrasonic Irrigation (n=25) and standard irrigation (n=25). The chemomechanical preparation will be performed with rotary nickel-titanium instruments. The irrigant used during instrumentaion will be NaOCl 2.5%; and EDTA 17% will be used to remove smear layer. The root canals were filled with calcium hydroxide for 14 days and then the canals will be obturated. Samples will be taken before (S1) and after preparation (S2); after the different irrigation prorocols (S3); and after intracanal medication (S4). Quantitative PCR (Real Time PCR) will be used to quantify the reduction of the bacterial load after disinfection. The Limulus amebocyte lysate (LAL) assay will be used for the quantification of endotoxins. Statistical analysis will be performed on treatment group and outcome of microbiologic tests to evaluate for significance. (AU)

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)

PRADO, LAIS CUNHA; GAVINI, GIULIO; SILVEIRA, AMANDA DA COSTA; NAKAMURA, VITOR CESAR; ALVES MAYER, MARCIA PINTO; PINHEIRO, ERICKA TAVARES. Comparison of rRNA-based reverse transcription PCR and rDNA-based PCR for the detection of streptococci in root canal infections. Journal of Applied Oral Science, v. 27, 2019. (16/15473-0, 13/02923-9)

NAKAMURA, V. C.; PINHEIRO, E. T.; PRADO, L. C.; SILVEIRA, A. C.; CARVALHO, A. P. L.; MAYER, M. P. A.; GAVINI, G.. Effect of ultrasonic activation on the reduction of bacteria and endotoxins in root canals: a randomized clinical trial. International Endodontic Journal, v. 51, n. 1, SI, p. E12-E22, JAN 2018. (13/02923-9)