title: In vitro comparisons of casting retention on implant abutments among commercially available and experimental castor oil-containing dental luting agents.
abstract: BACKGROUND
  Although cement-retained implant prostheses are widely used, the quantification of optimal retention remains controversial, and new dental luting agents should be evaluated.
  
  
  OBJECTIVE
  The purpose of this study was to compare, in vitro, the casting retention on implant abutments after cementation with 3 commercially available luting agents and an experimental luting agent (castor oil polyurethane, COP) with variable weight percentages (wt%) of calcium carbonate (CaCO3).
  
  
  METHODS
  Seventy-two palladium-silver cast copings were fabricated and divided into 6 groups: Temp Bond interim cement (TB); zinc phosphate cement (ZP); Rely X ARC resin cement (RX); pure COP (COP); COP + 10% wt% CaCO3 filler (COP 10); and COP + 50% wt% CaCO3 filler (COP 50). After cementation, the specimens were stored in distilled water at 37°C for 24 hours and subjected to removal force tests in a universal testing machine (5 kN; 0.5 mm/min). Statistical analyses were performed with the Kruskal-Wallis and Student-Newman-Keuls tests (α=.05).
  
  
  RESULTS
  The median values of casting retention (N) were as follows: TB=57.20 ±10.4; ZP=343.56 ±50.3; RX=40.07 ±9.7; COP=258.98 ±41.4; COP 10=466.57 ±79.3; and COP 50=209.63 ±31.4. The Kruskal-Wallis test showed significant differences among the groups (P<.01). TB and RX had the lowest mean retention values; COP, COP 10, and COP 50 were equal to ZP, and COP 10 had the highest retention.
  
  
  CONCLUSIONS
  The casting retention on implant-abutments provided by COP was similar to that of copings cemented with zinc phosphate and may be influenced by the addition of calcium carbonate.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araraquara Dental School, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil. ligia@foar.unesp.br
authors.forename: Lígia A P
authors.initials: LA
authors.lastname: Pinelli
authors.forename: Laiza M G
authors.initials: LM
authors.lastname: Fais
authors.forename: Weber A
authors.initials: WA
authors.lastname: Ricci
authors.forename: José M S N
authors.initials: JM
authors.lastname: Reis
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002119:Calcium Carbonate / Q000737:chemistry; D002368:Castor Oil / Q000737:chemistry*; D002484:Cementation / Q000379:methods*; D003442:Crowns; D003722:Dental Alloys / Q000737:chemistry; D003738:Dental Cements / Q000737:chemistry*; D059605:Dental Implant-Abutment Design; D017268:Dental Prosthesis Retention; D003799:Dental Stress Analysis / Q000295:instrumentation; D005054:Eugenol / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D010165:Palladium / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012116:Resins, Plant / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry; D015036:Zinc Phosphate Cement / Q000737:chemistry
chemical_list: D003722:Dental Alloys; D003738:Dental Cements; D011109:Polymethacrylic Acids; D011140:Polyurethanes; C462240:RelyX ARC; D019279:Resin Cements; D012116:Resins, Plant; C509865:poliquil; D014867:Water; D012834:Silver; D005054:Eugenol; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D010165:Palladium; C076899:Temp-Bond; D015036:Zinc Phosphate Cement; D002368:Castor Oil; D002119:Calcium Carbonate; D015034:Zinc Oxide