Avaliação quantitativa das discrepâncias entre relação cêntrica e máxima intercuspidação, utilizando a tomografia computadorizada volumétrica de feixe cônico

Abstract

This research has been based on a quantitative evaluation, and has aimed at measuring possible discrepancies between the maxillary (upper jaw) and mandible (lower jaw) positions of Centrical Relation (CR) and Maximum Interspitting (MI), using computed tomography volumetric cone beam (cone method beam).The sample of study has consisted of 20 young adults and asymptomatic which has been equally divided into four groups, the first group has been formed by patients with normal occlusion and the other three groups, by individuals with bad occlusion from class I, II and III, of Angle. Those patients had been initially subjected to carry out a device made of a type of resin "JIG of Lucia" in order to have their jaws handled and maintained in CR whenever desired. Patients had been referred to a clinic of Dental Radiology where they were submitted to two cone beam tomographic examinations in NewTom 3G device, the first one having occlusion in MI and second one by using "JIG's previously made. Evaluations were made in both frontal and lateral tomographic image cuta, showing the condyle articular fossa relation; as well as in cutting side to investigate the relationship anteroposterior between the upper central incisor (tooth 11) and the respective lower incisor in alignment with. Those images had been processed in the own software of the 3G Newtom device (Software QR NNT Version 2.00) and 10 tomographic image cuts were obtained per patient being four lateral sides and four front of the ATM's (in CR and MI, on both sides right and left) and two lateral sides of the incisors (CR and MI). Through the use of tools for linear and angular measures of another software unit Newtom 3G (Basic 3G) other 520 measurements were obtained and taken for statistical analysis. For that, T tests of Student and Tukey at 5% level were applied. Differences shown in whole sample were not statistically significant in despite of the fact that in 94.5% of the measuring evaluations taken between placements CR and MI intra and inter groups and between the right and left sides. Only the anteroposterior relation among incisors in the normal group had shown statistical significance between positions in CR and MI. This research has been based on a quantitative evaluation, and has aimed at measuring possible discrepancies between the maxillary (upper jaw) and mandible (lower jaw) positions of Centrical Relation (CR) and Maximum Interspitting (MI), using computed tomography volumetric cone beam (cone method beam).