title: Comparison of three-implant-supported fixed dentures and two-implant-retained overdentures in the edentulous mandible: a pilot study of treatment efficacy and patient satisfaction.
abstract: OBJECTIVE
  The mandibular two-implant overdenture has been shown to be a highly successful treatment. However, overdenture patients who desire a fixed prosthesis may not be satisfied with a removable overdenture. This prospective study sought to compare prosthetic outcomes, patient satisfaction, and survival rates of implants between two-implant-supported overdentures (IODs) and three-implant-supported fixed dentures (ISFDs).
  
  
  METHODS
  Twenty completely edentulous patients were randomly and equally assigned to two groups. New conventional complete dentures were made, and the mandibular denture was used as a surgical guide during implant placement. Implants were placed in one stage, followed by a mandibular denture soft reline (provisional loading). Ball attachments were inserted at 8 weeks, and ISFDs were delivered at 16 weeks. IODs were connected to the attachments at 8 weeks, using each patients's existing denture. The definitive ISFDs were fabricated using computer-aided design/computer-assisted manufacture milled titanium frameworks and acrylic resin base and teeth. Patient satisfaction and panoramic radiographs were investigated at 6 and 12 months.
  
  
  RESULTS
  Both treatments had significant and positive effects on patient satisfaction and quality of life. None of the 50 implants placed had failed at 12 months of follow-up; therefore, the implant survival rate was 100%. Prosthetic complications were generally rare and easily manageable.
  
  
  CONCLUSIONS
  Both the treatment modalities-the ISFD supported by three implants and the IOD supported by two implants-significantly and similarly improved patient satisfaction and oral health-related quality of life, and prosthetic complications were relatively rare for both treatments. Three implants can be used to support a mandibular fixed prosthesis; however, a longer observation period is needed to validate this treatment modality.
authors.affiliation: Department of Prosthodontics, University of North Carolina at Chapel Hill, USA.
authors.forename: Ingeborg J
authors.initials: IJ
authors.lastname: De Kok
authors.forename: Kuang-Han
authors.initials: KH
authors.lastname: Chang
authors.forename: Tsui-Shan
authors.initials: TS
authors.lastname: Lu
authors.forename: Lyndon F
authors.initials: LF
authors.lastname: Cooper
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000368:Aged; D017076:Computer-Aided Design; D015921:Dental Implants / Q000523:psychology; D003764:Dental Materials / Q000737:chemistry; D019094:Dental Prosthesis, Implant-Supported / Q000523:psychology; D003819:Denture Bases; D003779:Denture Design; D003823:Denture Rebasing; D003781:Denture Retention / Q000295:instrumentation / Q000523:psychology; D003826:Denture, Complete, Lower; D003828:Denture, Overlay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D057893:Immediate Dental Implant Loading; D007575:Jaw, Edentulous / Q000534:rehabilitation* / Q000601:surgery; D008297:Male; D008334:Mandible / Q000601:surgery*; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology; D017060:Patient Satisfaction; D010865:Pilot Projects; D011446:Prospective Studies; D011788:Quality of Life; D016019:Survival Analysis; D014025:Titanium / Q000737:chemistry; D016896:Treatment Outcome
chemical_list: D000180:Acrylic Resins; D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium