Search results for "Mandibular plane"
showing 8 items of 8 documents
Cephalometric measurements from 3D reconstructed images compared with conventional 2D images
2011
Abstract Objective: To assess whether the values of different measurements taken on three-dimensional (3D) reconstructions from cone-beam computed tomography (CBCT) are comparable with those taken on two-dimensional (2D) images from conventional lateral cephalometric radiographs (LCRs) and to examine if there are differences between the different types of CBCT software when taking those measurements. Material and Methods: Eight patients were selected who had both an LRC and a CBCT. The 3D reconstructions of each patient in the CBCT were evaluated using two different software packages, NemoCeph 3D and InVivo5. An observer took 10 angular and 3 linear measurements on each of the three types o…
A stereotactic device for rabbits based on mandibular and cranial landmarks
2008
✓ The authors have developed a stereotactic device for use in rabbits that uses the plane at the base of the mandible combined with cranial sutures as an anatomical reference. The device was developed for a study designed to evaluate catheters for infection prophylaxis, and this required the implantation of silicone catheters along a reproducible trajectory through the lateral ventricle. Cadaver and atlas studies demonstrated consistent spatial relationships between intracranial structures and the surface plane on which the animals were resting during the surgery. This plane is formed by the 2 mandibular angles and the mandibular tip. The authors developed a stainless steel stereotactic dev…
Hyoid bone position in different facial skeletal patterns
2018
Background Hyoid bone plays a significant role in physiological functions of craniofacial region and it’s position adapts to changes of the head. The purpose of this study was to determine the position of the hyoid bone among subjects with class I, class II and class III skeletal patterns and evaluate the gender differences. Material and Methods One hundred and ten lateral cephalograms (59 females and 51 males) from different skeletal patterns (class I, II and III) were selected. The skeletal patterns were determined according to ANB angle. Using MicroDicom software, different linear and angular measurements (6 variables) was carried out to determine the position of hyoid bone. Intraclass c…
Does muscular activity related to vertical facial divergence influence the time needed for orthodontic extrusion of palatally impacted maxillary cani…
2018
Background The aim of the present study was to evaluate if the different muscular activity correlated to different degrees of facial divergence has an effect on the time needed to extrude a palatally impacted maxillary canine. Material and methods Twenty-six patients were retrospectively selected, all treated with a specific cantilever appliance that allows extrusion of the impacted canine applying a physiologic amount of force below 0.6 N in a predictable way. For all the patients, pre-treatment cephalometric tracings were used to evaluate facial divergence through the FMA angle, the angle between the maxillary and mandibular plane, and the angles between the occlusal plane and either the …
Post-orthodontic position of lower incisors and gingival recession: A retrospective study
2017
Background To evaluate if changes in lower incisor position following orthodontic treatment are correlated with development of gingival recessions. Material and methods Pre- and post-treatment digital models and lateral cephalograms of 22 subjects were collected retrospectively. The clinical crown length, gingival scallop, and papilla height of the central lower incisor were measured along with the cephalometric incisor's inclination, the distance from the mandibular plane, and the distance between the Infradentale and Menton points. Statistical correlations between gingival and cephalometric variables were studied. In addition, two groups were defined based on the post-treatment incisor in…
Study between anb angle and Wits appraisal in cone beam computed tomography (CBCT)
2013
Objectives: To analyse the ANB and Wits values and to study correlations between those two measurements and other measurements in diagnosing the anteroposterior maxilo-mandibular relationship with CBCT. Study Design: Ninety patients who had previously a CBCT (i-CAT®) as a diagnostic register were selected. A 3D cephalometry was designed using one software package, InVivo5®. This cephalometry included 3 planes of reference, 3 angle measurements and 1 linear measurement. The means and standard deviations of the mean of each measurement were assessed. After that, a Pearson´s correlation coefficient has been performed to analyse the significance of each relationship. Results: When classifying t…
Effect of orthodontic treatment involving first premolar extractions on mandibular third molar angulation and retromolar space
2016
Background Third molars present more problems than other teeth because they are the last teeth to erupt, and so it is important to assess their development when designing an orthodontic treatment plan. The aim of this study was to compare the angulation of the mandibular third molar and retromolar space before and after orthodontic treatment in cases involving first premolar extraction. Material and methods 76 patients, 59 women (77.63%) and 17 men (22.36%), were recruited from the Orthodontics Clinic at Benemerita Universidad Autonoma de Puebla (Mexico). Panoramic radiographs were analyzed before and after orthodontic treatment that included first premolar extractions, measuring retromolar…
Orthodontic camouflage versus orthognathic surgery for class III deformity: comparative cephalometric analysis
2017
The objective of this study was to compare different cephalometric variables in adult patients with class III malocclusions before and after treatment, in order to determine which variables are indicative of orthodontic camouflage or orthognathic surgery. The cases of 156 adult patients were assessed: 77 treated with orthodontic camouflage and 79 treated with orthodontics and orthognathic surgery. The following cephalometric variables were measured on pre-treatment (T1) and post-treatment (T2) lateral cephalograms: sella-nasion-A-point (SNA), sella-nasion-B-point (SNB), and A-point-nasion-B-point (ANB) angles, Wits appraisal, facial axis angle, mandibular plane angle, upper and lower inciso…