title: A comparison of MTA, Super-EBA, composite and amalgam as root-end filling materials using a bacterial microleakage model.
abstract: OBJECTIVE
  The aim of this study was to compare traditional and newly developed root-end filling materials for resistance to bacterial microleakage.
  
  
  METHODS
  Sixty extracted single-rooted teeth were randomly divided into five groups for root-end filling with mineral trioxide aggregate, Super-EBA, TPH composite resin with ProBond dentine bonding agent, Dispersalloy amalgam with and without ProBond, and positive and negative control groups. Root canals were instrumented using the step-back technique and simulated root-end resections performed. Root-end filling materials were placed in 3 mm ultrasonic retropreparations. Nail varnish was applied to all external root surfaces to the level of the resected root ends to prevent lateral microleakage. Samples were sterilized in an ethylene oxide sterilizer for 12 h. Using a newly designed model system, the apical 3-4 mm of the roots were immersed in BHI culture medium with phenol red indicator within culture chambers. The coronal access of each specimen was inoculated every 48 h with a suspension of Streptococcus salivarius. Culture media were observed every 24 h for colour change indicating bacterial contamination. Media demonstrating colour change were plated for S. salivarius. Samples were observed for 12 weeks.
  
  
  RESULTS
  At 4 weeks 10% of specimens from each experimental group had evidence of leakage. At 8 weeks 20% of specimens filled with amalgam without dentine bonding agent, Super-EBA and MTA had evidence of leakage. At 12 weeks minor differences between materials were noted.
  
  
  CONCLUSIONS
  Under the conditions of the study, despite some variations, there were no statistically significant differences in rate of microleakage among the five groups tested at either 4, 8 or 12 weeks.
authors.affiliation: Department of Endodontics, New York University College of Dentistry 100104086, USA.
authors.forename: H L
authors.initials: HL
authors.lastname: Adamo
authors.forename: R
authors.initials: R
authors.lastname: Buruiana
authors.forename: L
authors.initials: L
authors.lastname: Schertzer
authors.forename: R J
authors.initials: RJ
authors.lastname: Boylan
mesh_terms: D017607:Aluminum Compounds; D017610:Calcium Compounds; D003763:Dental Leakage / Q000517:prevention & control*; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; D006801:Humans; D010087:Oxides; D011897:Random Allocation; D012184:Retrograde Obturation / Q000379:methods*; D012387:Root Canal Filling Materials; D017640:Silicates
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; C084074:Super EBA