title: Fracture Behavior of Minimally Invasive, Posterior, and Fixed Dental Prostheses Manufactured from Monolithic Zirconia.
abstract: To compare ultimate fracture load (Fu), load at first damage (F1d), and fracture pattern for posterior fixed dental prostheses (FDPs) manufactured from translucent, yttria-stabilized zirconia polycrystal.
  
  
  
  Premolar-size FDPs in 4 test groups (n = 16/group) were constructed as veneered complete crown-retained (group 1), monolithic complete crown-retained (group 2), monolithic partial veneer crown-retained (group 3), or monolithic resin-bonded (group 4) prostheses with minimum zirconia wall thickness (0.5 mm). Adhesively cemented to metal abutments, half of the prostheses were artificially aged by use of 10,000 thermocycles (6.5°C/60°C) and 1,200,000 chewing cycles (F = 108 N), before fracture loading. Statistics included two-way non-parametric ANOVA and Dunn-Bonferroni post-hoc tests (α = 0.05).
  
  
  
  None of the restorations failed during artificial aging. Fuwas affected by test group (p < 0.001); F1dwas also affected by the factor combination of test group and aging (p = 0.001 for test group; p = 0.049 for test group*aging). Mean Fufor all groups exceeded 1000 N; it was comparable for group 1 and group 2 and statistically significantly higher for group 2 and group 3 than for group 4 (p < 0.01). Fracture usually occurred through the retainer wall. F1d= 200 N was determined for individual samples in group 1 (chipping) and group 3 (local debonding).
  
  
  
  Fuof all the restorations was adequate for clinical use. Complications might, however, be expected at forces below 500 N for veneered prostheses (chipping) as well as for monolithic partial veneer crown-retained prostheses (local debonding).
  
  
  
  With regard to fracture behavior, all-ceramic complete crown-retained fixed dental prostheses (FDP) manufactured from monolithic zirconia, with a retainer wall thickness of 0.5 mm, might be suitable for use as a conservative alternative to their veneered counterparts in the rehabilitation of posterior tooth loss. Monolithic zirconia resin-bonded FDP might, moreover, be a viable alternative to resin-bonded FDPs with metal adhesive retainers in posterior arches, with improved esthetics and biocompatibility. The performance of both should, however, be verified in clinical trials. (J Esthet Restor Dent 28:367-381, 2016).
authors: Doctor of Medical Dentistry, Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Germany.
authors: Wolfgang
authors: W
authors: Bömicke
authors: Engineer Diploma, Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Germany.
authors: Stefan
authors: S
authors: Rues
authors: Doctor of Medical Dentistry, Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Germany.
authors: Verena
authors: V
authors: Hlavacek
authors: Professor Doctor of Medical Dentistry, Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Germany.
authors: Peter
authors: P
authors: Rammelsberg
authors: Professor Doctor of Medical Dentistry, Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Germany.
authors: Marc
authors: M
authors: Schmitter
mesh_terms: D003764:Dental Materials; D003776:Dental Porcelain; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003830:Denture, Partial, Fixed; D015040:Zirconium
chemical_list: D003764:Dental Materials; D003776:Dental Porcelain; D015040:Zirconium; C028541:zirconium oxide