title: In vitro performance of implant-supported monolithic zirconia crowns: Influence of patient-specific tooth-coloured abutments with titanium adhesive bases.
abstract: OBJECTIVE
  To investigate the influence of the combination of patient-specific abutments and titanium adhesive bases on the long-term in vitro performance of anterior crowns.
  
  
  METHODS
  Ten systems of screw-retained implant and adhesive base combinations (n=8/group) were restored with zirconia or polyetherketone (PEEK) abutments and identical full-anatomical zirconia crowns. For simulating clinical anterior loading, implants were fixed at an angle of 135° and submitted to prolonged thermal cycling and mechanical loading (TC: 6×3000 cycles, 5°C/55°C; ML: 100N, 3.6×10(6) cycles) to cause and register fatigue failure. Failed restorations were examined by means of scanning electron microscopy. Surviving restorations were loaded to fracture. Data (mean±standard deviation) were statistically analyzed (ANOVA; Bonferroni; Kaplan-Meier-Log-Rank; α=0.05).
  
  
  RESULTS
  Seven systems survived TCML without any failure. The other three systems showed loosening and fracturing of the screw (0.4-1.6×10(6) loadings) or debonding between base and abutment (0.002-3.4×10(6) loadings). None of the systems showed any fracture of the crown or failed bonding between abutment and crown. The Log-Rank test showed significant (p=0.000) differences. Fracture data significantly varied (ANOVA p=0.000) between the individual systems (minimum: 371N; maximum: 763N). Failures were mostly caused by bending or fracturing of the screw and in three cases by fracture of the abutment.
  
  
  CONCLUSIONS
  Anterior implant-supported zirconia crowns on titanium adhesive bases and bonded patient-specific zirconia abutments provided good in vitro performance and high fracture resistance. Sufficient high torque moments and early re-screwing may be advised.
  
  
  CONCLUSIONS
  Most adhesive base and abutment combinations may be appropriate for anterior application. Individual improvements may contribute to enduring success.
authors.affiliation: Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg 93042, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Rosentritt
authors.affiliation: Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg 93042, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Rembs
authors.affiliation: Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg 93042, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Behr
authors.affiliation: Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg 93042, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Hahnel
authors.affiliation: Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg 93042, Germany. Electronic address: verena.preis@ukr.de.
authors.forename: Verena
authors.initials: V
authors.lastname: Preis
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D003442:Crowns; D000044:Dental Abutments; D059605:Dental Implant-Abutment Design / Q000379:methods*; D019250:Dental Implants, Single-Tooth; D003764:Dental Materials / Q000737:chemistry; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D000269:Adhesives; D003764:Dental Materials; D019279:Resin Cements; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide
keywords: Abutment; Chewing simulation; Implant; PEEK; Titanium adhesive base; Zirconia