title: Seven-year clinical follow-up study of Probond ceramic crowns.
abstract: OBJECTIVE
  The Probond metal-ceramic system was proposed as an alternative to conventional metal-ceramic restorations. This study examined the 7-year survival and clinical performance of Probond metal-ceramic crowns.
  
  
  METHODS
  A total of 200 patients were included in the study. All subjects required single-unit fixed prosthodontics in various areas of the mouth. The patients without any active periodontal or pulpal diseases, having adequate tooth structure and good oral hygiene, were included in the study, while patients with parafunctional habits were excluded. Overall clinical performance over 7 years was determined by using modified USPHS criteria and evaluated with Kaplan-Meier survival analysis.
  
  
  RESULTS
  Seven failures were recorded among the 260 crowns placed. In the 4th year, 2 Probond crowns had minimal incisal fractures, and 1 restoration had a cervical fracture in the 2nd year. After 7 years, 2 Probond crowns were replaced with new Probond crowns as a result of fracture or trauma. Two restorations lost their occlusal contact integrity due to marginal ridge fractures. The formation of cracks and fractures as well as caries were significant (P <.05) at the 4- and 7-year recalls. Overall survival rates for marginal integrity, color stability, caries and crack formations, and occlusal integrity were 90.7%, 98.1%, 98.1%, 95.4%, and 99%, respectively, at 7 years.
  
  
  CONCLUSIONS
  The durability of Probond ceramic crown restorations proved to be successful after 7 years.
authors.affiliation: Department of Prosthodontics, Ege University School of Dentistry, Izmir, Turkey. maligungor@yahoo.com
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Güngör
authors.forename: Celar
authors.initials: C
authors.lastname: Artunç
authors.forename: Mine
authors.initials: M
authors.lastname: Dündar
mesh_terms: D000328:Adult; D002516:Ceramics / Q000737:chemistry*; D003442:Crowns; D003731:Dental Caries / Q000150:complications; D018772:Dental Marginal Adaptation; D019232:Dental Restoration Failure; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D018709:Statistics, Nonparametric