title: First clinical experiences with CAD/CAM-fabricated PMMA-based fixed dental prostheses as long-term temporaries.
abstract: OBJECTIVE
  The clinical performance of polymethylmethacrylate (PMMA)-based fixed dental prostheses (FDP) was evaluated in the indication of long-term temporaries.
  
  
  METHODS
  In the current indication of the applied machinable PMMA-based material (Vita CAD-Temp), i.e. temporary crowns and FDPs, 27 patients with compromised dentitions (uncertain dental prognosis or postponement of a removable treatment option) were recruited and 45 FDPs (3 or 4 units, 37 terminal-retained, 8 cantilevered) were inserted. Frameworks were computer-aided design (CAD)/computer-aided manufacturing (CAM)-manufactured after conventional impression taking and labside scanning of stone master casts. A resin-modified hybrid cement material (RelyX Unicem) was used for luting in a conventional protocol. Clinical follow-up was performed biannually.
  
  
  RESULTS
  Over an observation time from 2 to 26 months (median 13 months), 11 complications were found in 9 out of 45 PMMA restorations: 4 losses of retention, 5 complete fractures; two of these subsequent to a trepanation for endodontic treatment. Thereby, 3 out of 8 cantilevered FDPs had to be removed within 8 months. Thus, the statistical evaluation included FDPs with abutment at end, only. These standard design FDPs (n = 37) showed a 90.4 % survival rate with a complication-free rate of 88.3 % estimated for an observation time of 16 months.
  
  
  CONCLUSIONS
  Cantilevered FDPs and reconstructions on abutment teeth with markedly reduced biological prognosis or endodontic intervention yielded a high-failure rate. Terminal-retained FDPs performed clinically well in cases without compromised abutment teeth.
  
  
  CONCLUSIONS
  PMMA-based material might be used successfully for long-term temporization with 3- to 4-unit FDPs in a standard design over at least one year.
authors.affiliation: Department of Prosthodontics with Section "Medical Materials and Technology" at the Centre of Dentistry, Oral Medicine and Maxillofacial Surgery with Dental School, Tuebingen University Hospital, Osianderstr. 2-8, 72076, Tübingen, Germany. fabian.huettig@med.uni-tuebingen.de.
authors.forename: Fabian
authors.initials: F
authors.lastname: Huettig
authors.affiliation: Department of Prosthodontics with Section "Medical Materials and Technology" at the Centre of Dentistry, Oral Medicine and Maxillofacial Surgery with Dental School, Tuebingen University Hospital, Osianderstr. 2-8, 72076, Tübingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Prutscher
authors.affiliation: Department of Prosthodontics with Section "Medical Materials and Technology" at the Centre of Dentistry, Oral Medicine and Maxillofacial Surgery with Dental School, Tuebingen University Hospital, Osianderstr. 2-8, 72076, Tübingen, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Goldammer
authors.affiliation: Department of Prosthodontics with Section "Medical Materials and Technology" at the Centre of Dentistry, Oral Medicine and Maxillofacial Surgery with Dental School, Tuebingen University Hospital, Osianderstr. 2-8, 72076, Tübingen, Germany.
authors.forename: Curt A
authors.initials: CA
authors.lastname: Kreutzer
authors.affiliation: Department of Prosthodontics with Section "Medical Materials and Technology" at the Centre of Dentistry, Oral Medicine and Maxillofacial Surgery with Dental School, Tuebingen University Hospital, Osianderstr. 2-8, 72076, Tübingen, Germany.
authors.forename: Heiner
authors.initials: H
authors.lastname: Weber
mesh_terms: D003188:Composite Resins; D017076:Computer-Aided Design; D003442:Crowns; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D003830:Denture, Partial, Fixed; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D019279:Resin Cements
chemical_list: D003188:Composite Resins; C483701:Rely X Unicem; D019279:Resin Cements; C520134:VITA CAD-Temp; D019904:Polymethyl Methacrylate
keywords: CAD/CAM; Clinical study; Dental restorations; Micro-reinforced polymers; Prospective; Temporization