title: Accuracy of torque-limiting devices used for mini-implant placement--an in vitro study.
abstract: BACKGROUND
  Mini-implants are used when enhanced orthodontic anchorage is needed. Documented risks include damage inflicted to tooth structures and implant loosening, but also fracture. An important factor in minimizing adverse side effects is to control the insertion torque. The goal of the present study was to investigate the accuracy of various torque-limiting devices available for this purpose.
  
  
  METHODS
  Eight torque-limiting devices were analyzed, including a group of manually-operated drivers (n=3), a group of battery-operated drivers (n=4), and a surgical unit (n=1). The accuracy of these devices was tested over the entire range of applicable torque levels, using an experimental design simulating the insertion of mini-implants.
  
  
  RESULTS
  No significant differences were noted between the group of manually-operated and the group of battery-operated devices within the clinically relevant range of 10-25 Ncm. Comparing the individual devices revealed several significant differences. Some devices yielded both effective torque levels very close to the set levels and small standard deviations.
  
  
  CONCLUSIONS
  Mini-implants can be put in place in a controlled fashion regardless of whether the torque-limiting device used for this purpose is a manual- or battery-operated driver or a surgical unit. However, we observed that the accuracy of torque limitation differed greatly between individual devices across these groups. Our results can therefore help clinicians select an appropriate insertion device for mini-implants.
authors: Policlinic of Orthodontics, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
authors: Alexander
authors: A
authors: Pauls
authors: Manuel
authors: M
authors: Nienkemper
authors: Dieter
authors: D
authors: Drescher
mesh_terms: D003757:Dental Implantation / Q000295:instrumentation* / Q000379:methods*; D015921:Dental Implants; D004867:Equipment Design; D019544:Equipment Failure Analysis; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation* / Q000379:methods*; D016382:Orthodontic Appliance Design; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019415:Torque
chemical_list: D015921:Dental Implants