title: A systematic review of dowel (post) and core materials and systems.
abstract: OBJECTIVE
  The aim of this systematic review was to determine which dowel (post) and core system is the most successful when used in vivo to restore endodontically treated teeth.
  
  
  METHODS
  A MEDLINE, a Cochrane, and an EMBASE search (three specified searches) were conducted to identify randomized (RCT) and nonrandomized controlled clinical trials (CCT), cohort (CS), and case control studies (CCS) until January 2008, conducted on humans, and published in English, German, and French, relating to dowel and core systems for restoring endodontically treated teeth. Also, a hand search was conducted, along with contact with the authors when needed.
  
  
  RESULTS
  The MEDLINE, Cochrane, and EMBASE searches identified 997, 141, and 25 published articles, respectively. Ten articles from the MEDLINE and seven articles from the Cochrane search (that were also identified in the MEDLINE search) met the inclusion and validity assessment criteria. Six out of the ten studies were RCTs, two were CCTs, and two CSs. The RCT studies suggest that carbon fiber in resin matrix dowels are significantly better than precious alloy cast dowels (number needed to treat, NNT = 8.30). Tapered gold alloy cast dowels are better than ParaPost gold alloy cast dowels (NNT = 13.15). ParaPost prefabricated dowels are slightly better than ParaPost cast dowels (NNT = 175.4). Glass fiber dowels are significantly better than metal screw dowels (NNT = 5.46), but worse than titanium (NNT =-21.73) (moderately). Carbon fiber dowels are worse than gold alloy cast dowels (significantly) (NNT =-5.81) and than amalgam dowels (NNT =-125) (slightly). The CCT studies suggest that metal dowels are better (NNT = 21.73) but also worse than cast dowels (NNT =-33.33) depending on the remaining amount of coronal hard tissue. Quartz fiber dowels show success rates similar to and worse than glass fiber-reinforced dowels (NNT =-37.03). The results from the CS studies suggest that carbon fiber in resin matrix dowels are better (moderately) than carbon fiber + quartz and quartz fiber dowels. Titanium dowels with a composite build-up are better (moderately) than gold alloy cast dowels.
  
  
  CONCLUSIONS
  According to the studies of the highest levels of evidence, carbon fiber in resin matrix dowels are significantly better than precious alloy cast dowels (RCT). Glass fiber dowels are significantly better than metal screw dowels (RCT) and moderately better than quartz fiber dowels (CCT). Carbon fiber dowels are significantly worse than metal dowels (of precious alloy) (RCT). Prefabricated metal dowels are slightly better than cast dowels (RCT), but moderately worse when no collar of the dentin above the gingiva could be achieved (CCT).
authors.affiliation: joanna_theodosopoulou@yahoo.gr
authors.forename: Joanna N
authors.initials: JN
authors.lastname: Theodosopoulou
authors.forename: Konstantinos M
authors.initials: KM
authors.lastname: Chochlidakis
mesh_terms: D002244:Carbon / Q000627:therapeutic use; D000077482:Carbon Fiber; D003188:Composite Resins / Q000627:therapeutic use; D003722:Dental Alloys / Q000627:therapeutic use; D004955:Esthetics, Dental; D055094:Evidence-Based Dentistry; D005899:Glass Ionomer Cements / Q000627:therapeutic use; D006801:Humans; D017063:Outcome Assessment, Health Care; D011176:Post and Core Technique / Q000295:instrumentation*; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012390:Root Canal Therapy / Q000295:instrumentation*
chemical_list: D000077482:Carbon Fiber; D003188:Composite Resins; D003722:Dental Alloys; D005899:Glass Ionomer Cements; D012387:Root Canal Filling Materials; D002244:Carbon