title: Fracture resistance of immature teeth filled with BioAggregate, mineral trioxide aggregate and calcium hydroxide.
abstract: Abstract -  Background: The aim of this in vitro study was to assess the long-term fracture resistance of human immature permanent teeth filled with BioAggregate (BA), mineral trioxide aggregate (MTA) and calcium hydroxide (CH).
  
  
  METHODS
  The study consisted of single rooted premolar teeth with immature root formation extracted for orthodontic reasons. A total of 28 immature premolars with average root length of 10.7 mm and apical diameter of 3 mm were included in the study. The pulps were extirpated and the canals were prepared using an apical approach. The teeth were randomly assigned to four groups: Group I: DiaRoot(®) BA (DiaDent, Burnaby, BC, Canada), Group II: Angelus MTA (MTA-A; Angelus, Londrina, Brazil), Group III: ProRoot(®) MTA (MTA-PR; Dentsply, Tulsa, OK, USA), Group IV: CH (Sultan Chemists Inc., Englewood, NJ, USA). The teeth were placed in saline solution at 4°C for 1 year. The root of each tooth was then embedded in an acrylic resin block. All specimens were loaded at a crosshead speed of 1 mm min(-1) in an Instron testing machine and the peak loads up to fracture were recorded. Data were analysed statistically by Kruskal-Wallis and Mann-Whitney U-tests.
  
  
  RESULTS
  Mean (±SD) failure loads (MPa) were: 37.69 ± 14.43 for BA group, 32.94 ± 8.15 for MTA-A group, 28.74 ± 9.49 for MTA-PR group and 23.18 ± 8.48 for CH group. The BA group exhibited the highest fracture resistance and the CH group showed the lowest resistance to fracture. Significant differences (P < 0.05) in fracture resistance were found between the DiaRoot-BA and CH groups, and also between the MTA-A and CH groups.
  
  
  CONCLUSIONS
  Within the limitations of this study, data suggest that DiaRoot-BA-filled immature teeth demonstrate higher fracture resistance than other groups at 1 year. Considering the long-term risk of cervical root fracture associated with immature teeth, the use of DiaRoot-BA as a root canal filling material appears to be the most advantageous of the materials tested.
authors.affiliation: Departments of Pedodontics Endodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey.
authors.forename: Elif Bahar
authors.initials: EB
authors.lastname: Tuna
authors.forename: Muzaffer Emir
authors.initials: ME
authors.lastname: Dinçol
authors.forename: Koray
authors.initials: K
authors.lastname: Gençay
authors.forename: Oya
authors.initials: O
authors.lastname: Aktören
mesh_terms: D017607:Aluminum Compounds / Q000627:therapeutic use*; D001641:Bicuspid / Q000503:physiopathology*; D001729:Bismuth / Q000627:therapeutic use; D017610:Calcium Compounds / Q000627:therapeutic use*; D002126:Calcium Hydroxide / Q000627:therapeutic use*; D002648:Child; D003738:Dental Cements / Q000627:therapeutic use; D003799:Dental Stress Analysis / Q000295:instrumentation; D004338:Drug Combinations; D005500:Follow-Up Studies; D006801:Humans; D006882:Hydroxyapatites / Q000627:therapeutic use*; D008137:Longitudinal Studies; D009805:Odontogenesis / Q000502:physiology; D010087:Oxides / Q000627:therapeutic use*; D012184:Retrograde Obturation / Q000379:methods; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000379:methods; D017640:Silicates / Q000627:therapeutic use*; D012965:Sodium Chloride / Q000737:chemistry; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D019227:Tooth Apex / Q000473:pathology; D014082:Tooth Fractures / Q000503:physiopathology*; D014092:Tooth Root / Q000503:physiopathology
chemical_list: D017607:Aluminum Compounds; C557009:BioAggregate; D017610:Calcium Compounds; D003738:Dental Cements; D004338:Drug Combinations; D006882:Hydroxyapatites; C475480:MTA-Angelus; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; D012965:Sodium Chloride; D002126:Calcium Hydroxide; D001729:Bismuth