title: The single-tooth implant: a viable alternative for single-tooth replacement.
abstract: BACKGROUND
  The use of dental implants for single-tooth replacement cases introduces a challenge to the performance of these restorations. Clinical data suggest that single-tooth implant restorations do not benefit from lateral support from the surrounding dentition as do bridged implants, and that these restorations are subjected to greater masticatory forces. Therefore, single-tooth implants are exposed to an increased risk of failure. This prospective clinical trial was designed to evaluate the cumulative success rate of dual acid-etched single-tooth replacement implants in two clinical centers.
  
  
  METHODS
  The study protocol included 59 patients between 19 and 73 years. Implants were evaluated for mobility, infection, and crestal bone loss from 30.9 to 60 months.
  
  
  RESULTS
  Seventy-one (71) implants were placed in 59 patients, 20 male and 39 female. Forty-seven (47) were placed in the maxilla and 24 in the mandible. The percentages of anterior and posterior implants were 45.1% and 54.9%, respectively. A total of 13 (18.4%) implants were placed in soft, poor quality (Type IV) bone. Beginning 1 month post-implant placement, cases were followed for 30.9 to 60 months with a mean follow-up of 45.9 months. One implant failed (peri-implant infection) yielding an overall success rate of 98.6%.
  
  
  CONCLUSIONS
  This success rate for single-tooth replacement dual acid-etched implants compares favorably with bridged implants and with success rates of other single-tooth implant studies. Dual acid-etched implants performed well even under conditions of poor quality bone, where concomitant bone augmentation was performed, and when used for immediate replacement of extracted teeth.
authors.affiliation: Department of Periodontology, Baltimore College of Dental Surgery, University of Maryland, 21201, USA.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Mayer
authors.forename: Charles E
authors.initials: CE
authors.lastname: Hawley
authors.forename: John C
authors.initials: JC
authors.lastname: Gunsolley
authors.forename: Sylvan
authors.initials: S
authors.lastname: Feldman
mesh_terms: D000134:Acid Etching, Dental; D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation; D003758:Dental Implantation, Endosseous; D019250:Dental Implants, Single-Tooth; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019232:Dental Restoration Failure; D003830:Denture, Partial, Fixed; D005260:Female; D006801:Humans; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016019:Survival Analysis