title: A prospective, randomized, comparative clinical study of resin composite and glass ionomer cement for retrograde root filling.
abstract: OBJECTIVE
  To compare the clinical and radiographic treatment outcome of retrograde root filling with either dentin-bonded resin composite (Retroplast, RP) or glass ionomer cement (Chelon-Silver, CS).
  
  
  METHODS
  A prospective, randomized clinical study of 134 consecutive patients with indication of retrograde root filling of an incisor, canine, premolar, or first molar. Either RP or CS was chosen at random as retrograde filling material. Either material was applied onto the entire resection surface after prepared slightly concave. This preparation technique makes a sealing of the entire resection surface possible and prevents marginal contraction gaps during polymerization. A total of 122 patients were available for 1-year follow-up.
  
  
  RESULTS
  After 1 year the proportion of successful cases was significantly higher in the RP group (73%) than in the CS group (31%) (p<0.001). Doubtful healing with a need for a longer observation period was seen in 17% of the RP cases and 19% of the CS cases. The proportion of failures in the RP group (10%) was significantly lower than that in the CS group (50%) (p<0.001). Most of the unsuccessful CS cases failed due to loosening of the retrograde filling.
  
  
  CONCLUSIONS
  Dentin-bonded RP applied onto the entire, slightly concave resection surface is a predictable apical sealant characterized by a high success rate. In contrast, retrograde root filling with CS results in an unacceptably high failure rate due to insufficient bonding strength to the concave resection surface.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Faculty of Health Sciences, University of Copenhagen and University Hospital, Denmark. simon.storgaard@jensen.mail.dk
authors.forename: S S
authors.initials: SS
authors.lastname: Jensen
authors.forename: A
authors.initials: A
authors.lastname: Nattestad
authors.forename: P
authors.initials: P
authors.lastname: Egdø
authors.forename: I
authors.initials: I
authors.lastname: Sewerin
authors.forename: E C
authors.initials: EC
authors.lastname: Munksgaard
authors.forename: S
authors.initials: S
authors.lastname: Schou
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D016722:Cermet Cements; D003188:Composite Resins; D019232:Dental Restoration Failure; D005260:Female; D005899:Glass Ionomer Cements; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D012184:Retrograde Obturation / Q000379:methods*; D012387:Root Canal Filling Materials; D018030:Silver Compounds
chemical_list: D016722:Cermet Cements; D003188:Composite Resins; D005899:Glass Ionomer Cements; D012387:Root Canal Filling Materials; D018030:Silver Compounds; C067445:Chelon Silver; D017438:Bisphenol A-Glycidyl Methacrylate