title: Clinical Fitting and Adjustment Time for Implant-Supported Crowns Comparing Digital and Conventional Workflows.
abstract: OBJECTIVE
  The aim of this prospective cohort study was to investigate clinical and laboratory performance of implant-supported reconstructions comparing the digital to the conventional workflow.
  
  
  METHODS
  Twenty study participants were treated in a cross-over design for single-tooth replacement in posterior sites, each with a customized titanium abutment plus computer-assisted design and computer-assisted manufacturing (CAD/CAM)-zirconia-suprastructure (test: digital workflow; n = 20) and a standardized titanium abutment plus PFM-crown (control: conventional pathway; n = 20). Evaluation of the 40 reconstructions included: 1) feasibility of laboratory cross-mounting of each abutment-crown-connection, and 2) assessment of adaptation time for clinical adjustments of interproximal and occlusal surfaces. Statistical analyses were performed using the exact Wilcoxon rank sum tests.
  
  
  RESULTS
  Laboratory cross-mounting was feasible for three reconstruction pairings revealing a 15% vice versa transfer success rate. All implant crowns could be provided successfully within two clinical appointments, independently of the workflow used. The mean clinical adjustment time was significantly lower (p < .001) for test reconstructions from the digital workflow with 2.2 min (standard deviation [SD] ± 2.1) compared with the ones from the conventional pathway with 6.0 min (SD ± 3.9).
  
  
  CONCLUSIONS
  The digital workflow was almost threefold more efficient than the established conventional pathway for fixed implant-supported crowns. Clinical fitting could be predictably achieved with no or minor adjustments within the digital process of intraoral scanning plus CAD/CAM technology.
authors.affiliation: Department of Reconstructive Dentistry, University of Bern, Bern, Switzerland. tim.joda@zmk.unibe.ch.
authors.forename: Tim
authors.initials: T
authors.lastname: Joda
authors.affiliation: Department of Reconstructive Dentistry, University of Bern, Bern, Switzerland.
authors.forename: Joannis
authors.initials: J
authors.lastname: Katsoulis
authors.affiliation: Department of Reconstructive Dentistry, University of Bern, Bern, Switzerland.
authors.forename: Urs
authors.initials: U
authors.lastname: Brägger
mesh_terms: D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D003442:Crowns; D000044:Dental Abutments; D015921:Dental Implants; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017755:Prosthesis Fitting; D057188:Workflow
chemical_list: D015921:Dental Implants
keywords: CAD/CAM; conventional; cross-mounting; dental implant crown; digital; intraoral optical scan; workflow