title: One-stage operative procedure using two different implant systems: a prospective study on implant overdentures in the edentulous mandible.
abstract: BACKGROUND
  Evidence-based reports are needed to support the application of a one-stage surgical protocol for unsplinted implants supporting mandibular overdentures.
  
  
  OBJECTIVE
  To examine the feasibility and success of using two different dental implant systems (originally designed for two-stage operative technique) using a one-stage operative procedure in patients being rehabilitated with implant mandibular overdentures.
  
  
  METHODS
  The study sample involved 24 edentulous subjects (aged 55-80 yr) randomly allocated to two different implant systems, one with a machined titanium implant surface (Steri-Oss, Nobel Biocare, Göteborg, Sweden) and the other with a roughened titanium surface (Southern Implants, Ltd., Irene, South Africa). Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all patients, using a standardized one-stage surgical and prosthodontic procedure. Primary stability and bicortical anchorage of the implants was mandatory before healing abutments were connected at the time of implant placement. Implant overdentures and their respective matrices were inserted following a standard 12-week healing period. Data relating to mobility tests, radiographs, and peri-implant parameters were documented at 12, 16, and 52 weeks after surgery.
  
  
  RESULTS
  A success rate of 95.8% for the Steri-Oss and 100% for the Southern Implants was found, without any statistically significant differences in the marginal bone loss. Significant changes in Periotest values were observed for both types between 12 and 52 weeks (p < .001). Minor changes were observed in the peri-implant parameters evaluated.
  
  
  CONCLUSIONS
  These preliminary findings show a successful application of this one-stage approach for unsplinted implants supporting mandibular overdentures with Steri-Oss and Southern Implant Systems.
authors.affiliation: Department of Oral Rehabilitation, School of Dentistry, University of Otago, P.O. Box 647, Dunedin, New Zealand. andrew.tawse-smith@stonebow.otago.ac.nz
authors.forename: A
authors.initials: A
authors.lastname: Tawse-Smith
authors.forename: C
authors.initials: C
authors.lastname: Perio
authors.forename: A G
authors.initials: AG
authors.lastname: Payne
authors.forename: R
authors.initials: R
authors.lastname: Kumara
authors.forename: W M
authors.initials: WM
authors.lastname: Thomson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants / Q000009:adverse effects; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003826:Denture, Complete, Lower; D003828:Denture, Overlay; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000534:rehabilitation; D008297:Male; D008334:Mandible; D008875:Middle Aged; D017622:Periodontal Attachment Loss / Q000209:etiology; D011446:Prospective Studies; D018709:Statistics, Nonparametric
chemical_list: D015921:Dental Implants