title: Fracture Strength of Monolithic All-Ceramic Crowns on Titanium Implant Abutments.
abstract: OBJECTIVE
  The fracture strengths of all-ceramic crowns cemented on titanium implant abutments may vary depending on crown materials and luting agents. The purpose of this study was to examine differences in fracture strength among crowns cemented on implant abutments using crowns made of seven different monolithic ceramic materials and five different luting agents.
  
  
  METHODS
  In total, 525 crowns (75 each of Vita Mark II, feldspathic ceramic [FSC]; Ivoclar Empress CAD, leucite-reinforced glass ceramic [LrGC]; Ivoclar e.max CAD, lithium disilicate [LiDS]; Vita Suprinity, presintered zirconia-reinforced lithium silicate ceramic [PSZirLS]; Vita Enamic, polymer-reinforced fine-structure feldspathic ceramic [PolyFSP], Lava Ultimate; resin nanoceramic [ResNC], Celtra Duo; fully crystallized zirconia-reinforced lithium silicate [FcZirLS]) were milled using a CAD/CAM system. The inner surfaces of the crowns were etched and silanized. Titanium implant abutments were fixed on implant analogs, and airborne-particle abrasion was used on their exterior specific adhesion surfaces (Al2O3, 50 μm). Then, the abutments were degreased and silanized. The crowns were cemented on the implant abutments using five luting agents (Multilink Implant, Variolink II, RelyX Unicem, GC FujiCEM, Panavia 2.0). After thermocycling for 5,000 cycles (5 to 55°C, 30 seconds dwell time), the crowns were subjected to fracture strength testing under static load using a universal testing machine. Statistical analyses were performed using analysis of variance (α = .0002) and the Bonferroni correction.
  
  
  RESULTS
  No significant difference among the luting agents was found using the different all-ceramic materials. Ceramic materials LiDS, PSZirLS, PolyFSP, and ResNC showed significantly higher fracture strength values compared with FSC, FcZirLS, and LrGC. The PSZirLS especially showed significantly better results.
  
  
  CONCLUSIONS
  Within the limitations of this study, fracture strength was not differentially affected by the various luting agents. However, the fracture strength was significantly higher for PSZirLS, PolyFSP, ResNC, and LiDS ceramics than for the FSP, LrGC, and the FcZirLS ceramic with all luting agents tested.
authors.forename: Michael
authors.initials: M
authors.lastname: Weyhrauch
authors.forename: Christopher
authors.initials: C
authors.lastname: Igiel
authors.forename: Herbert
authors.initials: H
authors.lastname: Scheller
authors.forename: Gernot
authors.initials: G
authors.lastname: Weibrich
authors.forename: Karl Martin
authors.initials: KM
authors.lastname: Lehmann
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry; D017076:Computer-Aided Design; D003442:Crowns; D000044:Dental Abutments; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D015921:Dental Implants; D003764:Dental Materials; C542393:FujiCEM; D005899:Glass Ionomer Cements; C438843:Panavia-Fluoro; D011108:Polymers; D017680:Potassium Compounds; C483701:Rely X Unicem; D019279:Resin Cements; C000621298:VITA Suprinity; C082340:Vita Mark II; C493120:lithia disilicate; C502351:multilink adhesive system; D003776:Dental Porcelain; C016447:feldspar; C078519:leucite; C103502:Variolink; C023506:Glass ceramics; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide