title: Comparison of intracanal EndoSequence Root Repair Material and ProRoot MTA to induce pH changes in simulated root resorption defects over 4 weeks in matched pairs of human teeth.
abstract: BACKGROUND
  Intracanal mineral trioxide aggregate (MTA) may provide an alternative to calcium hydroxide in the treatment of external inflammatory root resorption. This in vitro study using human matched pairs of teeth compared white ProRoot MTA (WMTA; (Dentsply Tulsa Dental Specialties, Tulsa, OK) and an alternative material with purportedly improved handling properties, EndoSequence Root Repair Material (ES; Brasseler USA, Savannah, GA), by measuring pH in simulated root surface resorptive defects after intracanal placement. The null hypothesis tested was that there is no difference between WMTA and ES.
  
  
  METHODS
  Bilaterally matched pairs (n = 24) of extracted, human, single-rooted teeth were instrumented to apical size 50/.06, and root surface cavities were prepared at 5 mm and 2 mm from the apex. Root canals of experimental matched pairs (n = 20) were filled with WMTA or ES; control pairs (n = 4) were filled with calcium hydroxide (positive control [POS]) or saline (negative control [NEG]). Teeth were sealed coronally and apically and immersed in saline. The pH in root surface cavities was measured at 20 minutes, 3 hours, 24 hours, 1 week, 2 weeks, 3 weeks, and 4 weeks.
  
  
  RESULTS
  The pH at 5 mm when compared with the 2-mm level was significantly higher for the WMTA, ES, and POS groups (P < .05, paired t tests); therefore, each level was analyzed separately. At both the 2-mm and 5-mm levels, significant pH changes occurred over time in the WMTA, ES (both P < .0001, repeated-measures analysis of variance), and POS (P < .0001, Friedman test) groups and not in the NEG group (mean pH = 7.32 ± 0.04, P > .05). There were no differences between WMTA and ES at 20 minutes and 3 hours at both levels or at 24 hours at 5mm. The pH of WMTA was higher than ES by 24 hours at the 2-mm level (8.79 vs 8.56, P < .05, paired t test) and after 1 week at the 5-mm level (8.91 vs 8.05, P < .0001) and was thereafter always significantly higher in WMTA compared with ES (P < .0001). The null hypothesis was rejected.
  
  
  CONCLUSIONS
  In matched pairs of teeth, intracanal placement of WMTA compared with ES resulted in a higher pH in simulated root resorption defects that was time and root level dependent.
authors.affiliation: Department of Endodontology, School of Dentistry, Oregon Health and Science University, Portland, Oregon, USA.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Hansen
authors.forename: J Gordon
authors.initials: JG
authors.lastname: Marshall
authors.forename: Christine M
authors.initials: CM
authors.lastname: Sedgley
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry / Q000627:therapeutic use*; D017610:Calcium Compounds / Q000737:chemistry / Q000627:therapeutic use*; D002126:Calcium Hydroxide / Q000737:chemistry / Q000627:therapeutic use; D002130:Calcium Phosphates / Q000737:chemistry / Q000627:therapeutic use*; D016022:Case-Control Studies; D003786:Dental Pulp Cavity / Q000378:metabolism; D003804:Dentin / Q000378:metabolism; D004058:Diffusion; D004338:Drug Combinations; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000378:metabolism; D008422:Materials Testing; D010087:Oxides / Q000737:chemistry / Q000627:therapeutic use*; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000379:methods; D012391:Root Resorption / Q000503:physiopathology / Q000628:therapy*; D017640:Silicates / Q000737:chemistry / Q000627:therapeutic use*; D012965:Sodium Chloride; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013635:Tantalum / Q000737:chemistry / Q000627:therapeutic use*; D013997:Time Factors; D015040:Zirconium / Q000737:chemistry / Q000627:therapeutic use*
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D002130:Calcium Phosphates; D004338:Drug Combinations; C550603:EndoSequence root repair material; D006878:Hydroxides; D010087:Oxides; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D017640:Silicates; C086631:mineral trioxide aggregate; D012965:Sodium Chloride; D013635:Tantalum; C031356:hydroxide ion; D015040:Zirconium; D012973:Sodium Hypochlorite; D002126:Calcium Hydroxide