title: The effects of elevated hemoglobin A(1c) in patients with type 2 diabetes mellitus on dental implants: Survival and stability at one year.
abstract: BACKGROUND
  The authors conducted a prospective cohort study to determine whether poor glycemic control is a contraindication to implant therapy in patients with type 2 diabetes.
  
  
  METHODS
  The study sample consisted of 117 edentulous patients, each of whom received two mandibular implants, for a total of 234 implants. Implant-retained mandibular overdentures were loaded after a four-month healing period and followed up for an additional one year. The authors assessed implant survival and stability (by means of resonance frequency analysis) relative to glycated hemoglobin A1c (HbA1c) levels, with baseline levels up to 11.1 percent and levels as high as 13.3 percent over one year.
  
  
  RESULTS
  Implant survival rates for 110 of 117 patients who were followed up for one year after loading were 99.0 percent, 98.9 percent and 100 percent, respectively, for patients who did not have diabetes (n = 47), those with well-controlled diabetes (n = 44) and those with poorly controlled diabetes (n = 19). The authors considered the seven patients lost to follow-up as having had failed implants; consequently, their conservative estimates of survival rates in the three groups were 93.0 percent, 92.6 percent and 95.0 percent (P = .6510). Two implants failed at four weeks, one in the nondiabetes group and the other in the well-controlled diabetes group. Delays in implant stabilization were related directly to poor glycemic control.
  
  
  CONCLUSIONS
  The results of this study indicate that elevated HbA1c levels in patients with type 2 diabetes were not associated with altered implant survival one year after loading. However, alterations in early bone healing and implant stability were associated with hyperglycemia.
authors.affiliation: Dr. Oates is a professor, Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MCS 7888, San Antonio, Texas 78229-3900, e-mail oates@uthscsa.edu. Address correspondence to Dr. Oates.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Oates
authors.affiliation: Dr. Galloway is a former resident, Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio.
authors.forename: Patrick
authors.initials: P
authors.lastname: Galloway
authors.affiliation: Dr. Alexander is a clinical professor, Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio.
authors.forename: Peggy
authors.initials: P
authors.lastname: Alexander
authors.affiliation: Dr. Vargas Green is an associate professor, Department of Comprehensive Dentistry, School of Dentistry, University of Texas Health Science Center at San Antonio.
authors.forename: Adriana
authors.initials: A
authors.lastname: Vargas Green
authors.affiliation: Dr. Huynh-Ba is an associate professor, Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio.
authors.forename: Guy
authors.initials: G
authors.lastname: Huynh-Ba
authors.affiliation: Dr. Feine is a professor, Oral Health and Society Research Unit, Faculty of Dentistry, McGill University, Montreal, Quebec, Canada.
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Feine
authors.affiliation: Dr. McMahan is a professor, Department of Pathology, University of Texas Health Science Center at San Antonio.
authors.forename: C Alex
authors.initials: CA
authors.lastname: McMahan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015921:Dental Implants; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003828:Denture, Overlay; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D008297:Male; D008334:Mandible / Q000601:surgery; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology
chemical_list: D015921:Dental Implants; D006442:Glycated Hemoglobin
keywords: Implantology; bone biology; diabetes; implant stability quotient; resonance frequency analysis