title: Zirconium dioxide implant abutments for posterior single-tooth replacement: first results.
abstract: BACKGROUND
  Prefabricated implant abutments made of zirconium dioxide (yttria-stabilized polycrystalline tetragonal zirconia; Y-TZP) have proved to be useful in the esthetically demanding anterior region and may also be useful for premolar and molar replacement because of their obvious positive impact on the health of peri-implant soft tissues.
  
  
  METHODS
  Forty screw implants were inserted in the posterior region of 24 patients and provided with prefabricated all-ceramic abutments made of zirconium dioxide Y-TZP. Zirconia-based crowns were used as superstructures. The following parameters were used to document the state of soft tissue: the modified plaque index (mPI), sulcus fluid flow rate (SFFR), modified sulcus bleeding index (mSBI), and probing depth (PD). Additionally, implant stability was measured using an electronic mobility testing device.
  
  
  RESULTS
  All implants (N = 40) followed up after 6 months in function were osseointegrated and showed good stability. In the presence of good oral hygiene (mPI: 0.3), the parameters SFFR (16) and mSBI (0.7) were indicative of stable and healthy soft tissue. The mean PD was highest at the distal points of measurement (2.4 mm) and was generally at a low level. Neither implant loss nor crown fractures occurred. Chipping of parts of the veneering ceramic was registered in three cases (7.5%).
  
  
  CONCLUSIONS
  After 6 months in function, no mechanical failure was registered in any of the all-ceramic abutments. On clinical investigation, the peri-implant soft tissues were largely healthy and devoid of inflammation.
authors: Department of Prosthetic Dentistry and Dental Materials Sciences, Dental School and Clinics, Saarland University, Homburg/Saar, Germany.
authors: Frank P
authors: FP
authors: Nothdurft
authors: Peter R
authors: PR
authors: Pospiech
mesh_terms: D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation / Q000379:methods; D002516:Ceramics / Q000737:chemistry*; D003442:Crowns; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous; D019250:Dental Implants, Single-Tooth; D003764:Dental Materials / Q000737:chemistry*; D003774:Dental Plaque Index; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003801:Dental Veneers; D005260:Female; D005500:Follow-Up Studies; D005883:Gingival Crevicular Fluid / Q000378:metabolism; D006801:Humans; D008297:Male; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000601:surgery; D008875:Middle Aged; D009910:Oral Hygiene; D016348:Osseointegration / Q000502:physiology; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000145:classification; D011446:Prospective Studies; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003764:Dental Materials; C499362:yttria stabilized tetragonal zirconia; D015019:Yttrium; D015040:Zirconium