Stability of miniplates and miniscrews used for orthodontic anchorage: Experience with 492 temporary anchorage devices
Journal
Clinical Oral Implants Research
Journal Volume
19
Journal Issue
11
Pages
1188-1196
Date Issued
2008
Author(s)
Abstract
Objectives: The aim of this retrospective study was to evaluate systematically the potential factors that influence failure rates of temporary anchorage devices (TADs) used for orthodontic anchorage. Materials and methods: Data on 492 TADs (miniplates, pre-drilling miniscrews, and self-drilling miniscrews) in 194 patients were collected. The factors related to TAD failure were evaluated using univariate analysis and multivariate forward stepwise logistic regression analysis. Results: There were no significant differences in failure rates among the TADs for the following variables: gender, type of malocclusion, facial divergency, implantation site (buccal, lingual, or crestal/midpalatal), location (anterior or posterior), method of force application (power chain or Ni-Ti coil spring), arch (upper or lower), type of soft tissue (attached gingiva or removable mucosa), and most of the cephalometric measurements that reflect dento-cranio-facial characteristics. An increased failure rate was noted for the self-drilling miniscrew type of TAD, TADs used for tooth uprighting, those inserted on bone with lower density, those associated with local inflammation of the surrounding soft tissue, those loaded within 3 weeks after insertion, and those placed in patients with greater mandibular retrusion. Failure rates of the self-drilling miniscrews installed by an oral surgeon and by an orthodontist did not differ significantly. Conclusions: Inflammation of soft tissue surrounding a TAD and early loading within 3 weeks after insertion were the most significant factors predicting TAD failure. Both orthodontists and oral surgeons who install orthodontic TADs must undergo sufficient training to achieve clinical excellence. ? 2008 The Authors.
Other Subjects
adolescent; adult; article; bone plate; bone screw; cephalometry; child; dental care; electronics; equipment; female; human; instrumentation; male; middle aged; orthodontics; periodontal disease; retrospective study; statistical model; Adolescent; Adult; Bone Plates; Bone Screws; Cephalometry; Child; Dental Stress Analysis; Equipment Failure; Female; Humans; Logistic Models; Male; Middle Aged; Miniaturization; Orthodontic Anchorage Procedures; Orthodontic Appliance Design; Retrospective Studies; Tooth Movement; Young Adult
Type
journal article