The Effect of Chlorhexidine Mixed with Mineral Trioxide Aggregate on Bacterial Leakage of Apical Plug in Simulated Immature Teeth Using Human Fresh Saliva

OBJECTIVES: Apexification is a challenging treatment in necrotic open apices teeth and bacterial leakage is the main reason for the treatment failure. The aim of this study is to compare the effect of mixing mineral trioxide aggregate (MTA) with chlorhexidine (CHX) on microbial leakage in apexification treatment of simulated immature teeth. MATERIALS AND METHODS: In this experimental study, 44 intact central incisors were selected based on inclusion criteria. The coronal and 2 mm of apical part of the specimens were removed till all root segments were 12 mm long. The apical parts of the teeth were prepared using Profile #40/0.06 (Dentsply Maillefer, Ballaigues, Switzerland) in the apical to coronal direction to simulate open apices. The specimens were separated into experimental groups (n = 40) and control groups (n = 4). Group 1 delivered a 5 mm apical plug by MTA/H(2)O and group 2 delivered an apical plug by MTA/CHX 0.12%. The positive control group had no apical barrier; on the other hand, the negative control group had an apical barrier and two layers of nail varnish on entire root surface. The microbial leakage assessment was done by a dual-chamber apparatus using fresh human saliva after 10-week follow-up. The turbidity of the lower chamber containing the Brain Heart Infusion (BHI) solution was analyzed based on the McFarland (0.5) standard which utilizes spectrophotometry results. Data analyses were done using Chi-square, Kaplan–Meier, and log-rank tests. RESULTS: MTA/CHX group had lower microbial leakage percentage (P = 0.001) and longer time of leakage (P = 0.002) in compared with MTA/H(2)O group and the difference was statistically meaningful. CONCLUSION: Based on the results of this study, MTA/CHX mixture can reduce the amount of bacterial leakage.