Evaluation of mandibular interradicular spaces with cone beam computed tomography for orthodontic mini implant installation

Abstract

Achieving maximum anchorage without movement of the teeth in anchorage unit has been a great challenge in orthodontics and the success of the treatment plan is highly dependent on it. But determination of a proper site for installation of mini implants is still one of the most common problems in this field. Nowadays the use of CBCT which provides 3-D images with acceptable quality is being widely spreaded in all fields of dentistry such as orthodontics. Materials and Methods: In this study 40 CBCT images of mandibulars arch from distal of canine to mesial of second molar were studied. The images were sectioned axially in 2mm diameter and the reference point was CEJ. To determine interradicular spaces tangent lines were drawed buccolingually to the roots in axial section and the minimum distance between these two lines was measured. Results: The results of this survey demonstrated that interradicular spaces increase from CEJ to apex in all sites; and this increase is statistically significant (P<0.001). Comparing the 4 mm section in all sites showed significant increase from 3,4 (site) to 4,5 (site) and 5,6 to 6,7 while this increase was not statistically significant from 4,5 to 5,6.