title: Regaining apical patency after obturation with gutta-percha and a sealer containing mineral trioxide aggregate.
abstract: BACKGROUND
  MTA Fillapex (Angelus Solucoes Odontologicas, Londrina PR, Brazil) was introduced as a mineral trioxide aggregate (MTA)-based sealer used for endodontic obturation. There is a lack of research that evaluates the ability of different solvents to soften MTA-based sealers during retreatment. This study tested the ability of 4 commonly used endodontic solvents to soften gutta-percha and MTA Fillapex to allow for the re-establishment of apical patency.
  
  
  METHODS
  Eighty-six extracted maxillary anterior teeth were instrumented to the working length to a size 45 (.04 taper size). Teeth were divided into 2 groups (n = 43 for each group). MTA Fillapex was placed into all canals. Group 1 was obturated with gutta-percha to the working length, and group 2 was obturated 2 mm short of the working length to ensure the apical 2 mm was filled with sealer only. Both groups were divided into 4 subgroups (n = 10). The remaining teeth served as the control group. Each subgroup was exposed to 1 of the following solvents: chloroform, Endosolv R (Septodont, Saint-Maur, France), Endosolv E (Septodont), or eucalyptol.
  
  
  RESULTS
  Patency was re-established in 100% of the teeth in groups 1 and 2 when tested with chloroform or Endosolv E, 80% of the teeth in group 1 and 90% in group 2 when tested with eucalyptol, and 10% of the teeth in group 1 and 50% in group 2 tested when with Endosolv R. The chi-square test indicated there was a statistical difference between Endosolv R and the other tested solvents for both groups.
  
  
  CONCLUSIONS
  Chloroform, Endosolv E, and Eucalyptol soften GP and MTA Fillapex sufficiently to aid in re-establishing apical patency during endodontic retreatment.
authors.affiliation: US Army Dental Activity, Fort Gordon, Augusta, Georgia.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Carpenter
authors.affiliation: US Army Dental Activity, Fort Gordon, Augusta, Georgia. Electronic address: stephanie.j.sidow.mil@mail.mil.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Sidow
authors.affiliation: US Army Dental Activity, Fort Gordon, Augusta, Georgia.
authors.forename: Kimberly W
authors.initials: KW
authors.lastname: Lindsey
authors.affiliation: Department of Clinical Investigation, Fort Gordon, Augusta, Georgia.
authors.forename: Augustine
authors.initials: A
authors.lastname: Chuang
authors.affiliation: Department of Clinical Investigation, Fort Gordon, Augusta, Georgia.
authors.forename: James C
authors.initials: JC
authors.lastname: McPherson
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry* / Q000627:therapeutic use; D017610:Calcium Compounds / Q000737:chemistry* / Q000627:therapeutic use; D002725:Chloroform / Q000737:chemistry; D003511:Cyclohexanols / Q000737:chemistry; D004338:Drug Combinations; D000077591:Eucalyptol; D005052:Eucalyptus; D006171:Gutta-Percha / Q000737:chemistry* / Q000627:therapeutic use; D006801:Humans; D008422:Materials Testing; D039821:Monoterpenes / Q000737:chemistry; D010087:Oxides / Q000737:chemistry* / Q000627:therapeutic use; D019233:Retreatment; D012387:Root Canal Filling Materials / Q000737:chemistry* / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D017640:Silicates / Q000737:chemistry* / Q000627:therapeutic use; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D019227:Tooth Apex / Q000033:anatomy & histology*
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D003511:Cyclohexanols; D004338:Drug Combinations; C473452:Endosolv R; D039821:Monoterpenes; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; D012997:Solvents; C086631:mineral trioxide aggregate; D002725:Chloroform; D006171:Gutta-Percha; D000077591:Eucalyptol
keywords: MTA Fillapex; Mineral trioxide aggregate; patency; retreatment; sealer; solvent