Evaluation of tooth inclination in individuals treated with self-ligated brackets by cone beam computed tomography (CBCT)

• Grant number: 12/21393-8
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2013
• End date: April 30, 2015
• Field of knowledge: Health Sciences - Dentistry - Orthodontics
• Principal Investigator: Mauricio de Almeida Cardoso
• Grantee: Mauricio de Almeida Cardoso
• Host Institution: Centro de Ciências da Saúde. Universidade do Sagrado Coração (USC). Bauru , SP, Brazil

Abstract

This study will assess computed tomography examinations to evaluate the maxillary and mandibular tooth inclinations in individuals treated with self-ligated brackets, considering the reading of inclination of tooth crowns and applicability of the method. The study will be conducted on 15 patients selected among individuals searching for orthodontic treatment at the clinics of USC and PROFIS (Bauru-SP). The inclusion criteria will be minimum age of 14 years, facial pattern I, Caucasoid ethnicity, Class I malocclusion and minimum crowding of 2 mm in the maxillary and mandibular arches, with indication for treatment with extraction of premolars or orthopedic maxillary expansion. Passive self-ligated brackets Smart Clip with prescription MBT (3M, Monrovia, USA) will be bonded and the treatment will be conducted using the following sequence of archwires: .014" thermally activated nickel-titanium, followed by .016" nickel-titanium, .016"x.022" thermally activated nickel-titanium, .019"x.025" nickel-titanium and finally .019"x.025" stainless steel archwire. Cone beam computed tomographies (CBCT) will be obtained at two moments, before placement of corrective orthodontic appliances (moment 1) and at completion of alignment and leveling, immediately after placement of rectangular .019" x .025" stainless steel archwire (moment 2). The images, saved in DICOM format, will be manipulated on the software InVivoDental 5 for measurement of inclinations. The means of two measurements in each moment will be analyzed as study parameters and submitted to the Student t test (systematic error) and Dahlberg test (random error). The initial and final means of tooth inclinations will be submitted to the paired t test at a significance level of 5%. (AU)