Comparative study on canal preparation by three rotary sys-tems using CT scan (An in vitro study)

Comparative study on canal preparation by three rotary sys-tems using CT scan (An in vitro study) Dr. M.H. Zarrabi* - Dr. A. Talati** - Dr. S. Moradi** - Dr. L. Shakeri*** * - Associate Professor and Chief of Endodontics Dept. - Faculty of Dentistry – Mashhad University of Medical Sciences. **- Assistant Professor of Endodontics Dept. - Faculty of Dentistry – Mashhad University of Medical Sciences. *** - Endodontist. Background and Aim: Cleaning and shaping of the root canal system are important objectives in each root canal therapy. A lot of automatic devices are nowadays available on the market to simplify the preparation and decrease instrumentation time. The aim of this study was to com-pare root canal preparation by three NiTi rotary systems: Profile, Flexmaster and Race using CT scan. Materials and Methods: In this in - vitro study forty five single rooted human mandibular premolars, with root canal curvature between 20°- 30° and radius curvature between 5-7 mm, were divided into three similar groups. All teeth were shortened to the length of 15 mm. Pre-operative CT scan of each root were recorded at 2, 4, 6, 8, 10 mm cross sections from apices. Following canal shaping, post operative scans were superimposed on the original images by adobe photoshop 7 software. Changes in canal transportation, canal centering and shape of ca-nal were analyzed. Fisher's exact test was used to examine each cross – section statistically. Results: All three NiTi rotary systems could prepare canals without any transportation and de-viation of original shapes. These systems could also maintain canal centering with minimal deviation from the canal depth. Three NiTi rotary systems were independent of transportation, canal centering and shaping variables in all cross – sections. No statistically significant differ-ences were observed between these three systems (P>0.05). Conclusion: All three NiTi rotary systems, without any significant differences, can be recom-mended for clinical use. Key words: Canal preparation – Flexmaster – Profile – Race – CT scan.