title: Impact of a biological barrier in pulpectomies of primary molars.
abstract: OBJECTIVE
  The purpose of this in vitro study was to determine whether placement of a resorbable collagen barrier at the apical one third of the root canal could prevent extrusion of pulpectomy filling material.
  
  
  METHODS
  Twenty-five extracted primary mandibular second molars, with at least two thirds of root length remaining, were used. The apical third of each root was covered with utility wax, and teeth were embedded in acrylic. Carious tooth structure was removed, crowns were reduced to a flat surface, and canals were accessed and preflared. Working lengths were established by reducing file lengths 2 mm short of the anatomic apex. Cleaning and shaping was performed using hand and rotary files, and canals were irrigated with sodium hypochlorite and dried with paper points. CollaCote was randomly packed into 1 of 2 prepared canals, and obturation was performed with Vitapex. Postoperative radiographs were independently evaluated for the presence of overfilling, and data were statistically analyzed using chi-square analysis.
  
  
  RESULTS
  Overfilling was observed in 16% (4/25) of the CollaCote treated canals and in 42% (10/24) of canals when no barriers were used (P = .047).
  
  
  CONCLUSIONS
  The application of CollaCote at the apical one third of the canals did not completely prevent, but did significantly decrease, the risk for overfilling in primary molars.
authors.affiliation: Department of Pediatric Dentistry, University of Florida, Gainesville, USA.
authors.forename: Marlin S
authors.initials: MS
authors.lastname: Johnson
authors.forename: Leandro R
authors.initials: LR
authors.lastname: Britto
authors.forename: Marcio
authors.initials: M
authors.lastname: Guelmann
mesh_terms: D020341:Absorbable Implants; D002126:Calcium Hydroxide / Q000627:therapeutic use; D003094:Collagen / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000473:pathology; D004338:Drug Combinations; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000517:prevention & control; D006801:Humans; D008567:Membranes, Artificial; D008963:Molar / Q000000981:diagnostic imaging / Q000601:surgery*; D011670:Pulpectomy / Q000295:instrumentation*; D011859:Radiography; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods; D012828:Silicones / Q000627:therapeutic use; D014094:Tooth, Deciduous / Q000000981:diagnostic imaging / Q000601:surgery*
chemical_list: C488453:CollaCote; D004338:Drug Combinations; D008567:Membranes, Artificial; D012387:Root Canal Filling Materials; D012828:Silicones; C029584:calcium hydroxide, iodoform, silicone oil drug combination; D003094:Collagen; D002126:Calcium Hydroxide