title: Cemented versus screw-retained implant-supported single-tooth crowns: a 4-year prospective clinical study.
abstract: OBJECTIVE
  The purpose of this controlled prospective clinical study was to compare cemented and screw-retained implant-supported single-tooth crowns followed for 4 years following prosthetic rehabilitation with respect to peri-implant marginal bone levels, peri-implant soft tissue parameters, and prosthetic complications.
  
  
  METHODS
  Twelve consecutive patients were selected from a patient population attending the Implantology Department at the University of Padova. They all presented with single-tooth bilateral edentulous sites in the canine/premolar/molar region with adequate bone width, similar bone height at the implant sites, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts. Each patient received 2 identical implants (1 in each edentulous site). One was randomly selected to be restored with a cemented implant-supported single-tooth crown, and the other was restored with a screw-retained implant-supported single-tooth crown. Data on peri-implant marginal bone levels and on soft tissue parameters were collected 4 years after implant placement and analyzed to determine whether there was a significant difference with respect to the method of retention (cemented versus screw-retained).
  
  
  RESULTS
  All patients completed the study. All 24 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the 2 groups with respect to peri-implant marginal bone levels and soft tissue parameters.
  
  
  CONCLUSIONS
  The data obtained with this study suggested that the choice of cementation versus screw retention for single-tooth implant restorations is likely not based on clinical results but seems to be based primarily on the clinician's preference.
  
  
  CONCLUSIONS
  Within the limitations of this study, the results indicate that there was no evidence of different behavior of the peri-implant marginal bone and of the peri-implant soft tissue when cemented or screw-retained single-tooth implant restorations were provided for this patient population.
authors.affiliation: Department of Periodontology, University of Padova, Institute of Clinical Dentistry, Padova, Italy. paolovigolo@virgilio.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Vigolo
authors.forename: Andrea
authors.initials: A
authors.lastname: Givani
authors.forename: Zeina
authors.initials: Z
authors.lastname: Majzoub
authors.forename: Giampiero
authors.initials: G
authors.lastname: Cordioli
mesh_terms: D016301:Alveolar Bone Loss / Q000145:classification; D002484:Cementation; D003442:Crowns; D019250:Dental Implants, Single-Tooth; D003774:Dental Plaque Index; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D005500:Follow-Up Studies; D005884:Gingival Hemorrhage / Q000145:classification; D005891:Gingivitis / Q000145:classification; D006801:Humans; D016876:Metal Ceramic Alloys / Q000737:chemistry; D010514:Periodontal Pocket / Q000145:classification; D011446:Prospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D016876:Metal Ceramic Alloys