title: Five-year clinical trial using three attachment systems for implant overdentures.
abstract: OBJECTIVE
  The objective is to compare, in a prospective randomized clinical trial, three types of attachment systems for mandibular implant overdenture, focusing on costs, maintenance requirements and complications from baseline to the end of 5-year follow-up period.
  
  
  METHODS
  Sixty-nine fully mandibular and fully/partially maxillary edentulous patients received two screw-type Straumann implants, in the mandibular canine region. New overdentures with three types of attachment systems were inserted according to an early-loading protocol: Group B (balls, divided into Subgroup B.1 - retentive anchor with gold matrix and Subgroup B.2 - retentive anchor with titanium matrix) (n = 23), Group M (magnets) (n = 23) and Group L (locator) (n = 23).
  
  
  RESULTS
  The highest maintenance event number (195) was observed in Group B vs. 31 in Group L and 15 in Group M. Significantly more complications were recorded in Subgroup B.1 than in Subgroup B.2, Group M and Group L (P < 0.05). Group M registered the highest prosthetic success (82.6%) in the 5 years, followed by Group L (78.2%). Subgroup B.1 had the lowest success rate (50%). The magnet group recorded statistically significant higher costs, comparing with the other two groups (P < 0.05).
  
  
  CONCLUSIONS
  The three attachment systems functioned well after 5 years. The magnets had a low maintenance requirement and high success rate, despite the relatively increased initial costs. Retentive anchor with titanium matrix and locator may be a better choice from a financial point of view, taking into consideration the initial low cost of the components and also the reduced number of complications.
authors.affiliation: Concordia Dent Clinic, Bucharest, Romania; Implantology, FMAM, University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
authors.forename: Corina Marilena
authors.initials: CM
authors.lastname: Cristache
authors.forename: Ligia Adriana Stanca
authors.initials: LA
authors.lastname: Muntianu
authors.forename: Mihai
authors.initials: M
authors.lastname: Burlibasa
authors.forename: Andreea Cristiana
authors.initials: AC
authors.lastname: Didilescu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003365:Costs and Cost Analysis; D019094:Dental Prosthesis, Implant-Supported; D003781:Denture Retention / Q000379:methods*; D003828:Denture, Overlay; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000534:rehabilitation*; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D053441:Suture Anchors; D016896:Treatment Outcome
keywords: complications; costs; locator; magnet; prosthetic maintenance; retentive anchor