JOE august 2013 - One-Visit Versus Two-Visit Root Canal Treatment: Effectiveness in the Removal of Endotoxins and Cultivable Bacteria

One-Visit Versus Two-Visit Root Canal Treatment: Effectiveness in the Removal of Endotoxins
and Cultivable Bacteria
Ana Claudia C. Xavier, DDS, MSc, Frederico C. Martinho, DDS, MSc, PhD, Adriana Chung, DDS, MSc, Luciane D. Oliveira, DDS, MSc, PhD, Antônio O.C. Jorge, DDS, MSc, PhD, Ma rcia C. Valera, DDS, MSc, PhD, and Cla udio A.T. Carvalho, DDS, MSc, PhD

Abstract

Introduction: This clinical study was conducted to compare the effectiveness of 1-visit versus 2-visit root canal treatment in removing endotoxins and cultivable bacteria from primarily infected root canals. Methods: Forty-eight primarily infected root canals were selected and randomly divided into 4 groups: G1, 1% NaOCl; G2, 2% chlorhexidine (CHX) gel; G3, 1% NaOCl + Ca(OH)2; and G4, 2% CHX gel + Ca(OH)2 (all, n = 12). G1 and G2 involved 1-visit treatment, whereas G3 and G4 involved 2-visit treatment with the placement of Ca(OH)2 medica- tion for 14 days. Samples were collected before and after root canal procedures. A chromogenic LAL assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial counts. Results: Endotoxins and cultivable bacteria were detected in 100% of the initial samples. All treatment protocols were effective in reducing bacterial load from infected root canals: G1 (1% NaOCl, 99.97%), G2 (2% CHX gel, 99.75%), G3 (1% NaOCl + Ca(OH)2, 99.90%), and G4 (2% CHX gel + Ca(OH)2, 96.81%), respectively (P < .05). No differ- ences were found in bacterial load reduction when comparing 1-visit and 2-visit treatment groups, irrespec- tive of the irrigant tested (P > .05). Higher median percentage values of endotoxin reduction were achieved in the 2-visit treatment groups (G3, 98.01% and G4, 96.81%) compared with 1-visit treatment groups (G1, 86.33% and G2, 84.77%) (all P < .05). Conclusions: Both 1-visit and 2-visit root canal treatment protocols were effective in reducing bacteria and endotoxins, but they were not able to eliminate them in all root canals analyzed. Furthermore, 2-visit root canal treatment proto- cols were more effective in reducing endotoxins than 1-visit root canal treatment protocols. 

(J Endod 2013;39:959–964)

Key Words
Endotoxin, LAL, limulus amebocyte lysate assay, root canal

 Download paper in pdf