Dimensions of Atlas and its Relation with Jaws Rotation (CBCT Scan Study). (original) (raw)
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JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH, 2017
Introduction: Cone Beam Computed Tomography (CBCT) imaging recently has become a very common diagnostic tool in the orthodontic literature. Recent research work has shown that CBCT imaging would give additional information regarding the volumetric assessment of the craniofacial structures. However, the previous published work has not considered the impact of the anterior-posterior skeletal classification and the vertical skeletal pattern on the volumetric assessment of the maxillary and mandibular bones. Aim: To evaluate maxillary and mandibular volumes (MxV and MdV, respectively) in hyper-divergent skeletal Class II (CII) and normo-divergent skeletal Class I (CI) patients and to investigate any possible correlation between CBCT derived lateral cephalometric variables and the calculated volumes. Materials and Methods: CBCT images of 60 patients (30 patients: CI, 30 patients: CII) were obtained and processed with Mimics ® 17 software (Materialise, NV, Belgium). The threedimensional models of both jaws were reconstructed and the related volumes were calculated using a novel approach. CBCT based cephalograms were also derived and linear and angular measurements of the craniofacial complex were obtained. Significance tests were based on t-tests (alpha set at 5%) and Pearson's correlation coefficients were calculated. Results: No significant differences were detected between the two groups in the MxV (p=0.435) and the MdV (p=0.507). In the CI group, no or weak correlations were found between the volumetric measurements and the 2D variables. In the CII group, there was a strong correlation between both MxV and MdV and both the posterior facial height (r=0.60, 0.78 respectively) and the facial height index (r=0.62, 0.72 respectively). A negative moderate correlation was found between both MxV and MdV and the mandibular plane angle (r=-0.48,-0.44 respectively) and Bjork's sum (r=-0.48,-0.44 respectively). Conclusion: There were no significant differences in the MxV and MdV between CI and CII skeletal patterns. Some cephalometric variables had moderate to strong correlation with the MxV and MdV in the CII group.
Journal of Evolution of Medical and Dental Sciences, 2020
BACKGROUND We wanted to assess and compare the morphological deviations of the cervical vertebral column and cranial base angle in three different facial types that is hypodivergent, normodivergent and hyperdivergent groups and elucidate the aetiology behind the associations as well as clinical implications of the results. METHODS The study was conducted in the department of orthodontics wherein lateral cephalograms of 150 subjects in the age group of 18-25 years were taken and divided into three groups. The division of groups was made as per Steiner's mandibular plane angle i.e. Hyperdivergent group (SN-MP angle >34 degrees) Normodivergent group (SN-MP angle 26-34 degrees) Hypodivergent group (SN-MP angle < 26 degrees). Lateral cephalograms were traced and analysed to compare the variables by statistical analysis. Morphology of the cervical column was evaluated by visual inspection of the first 5 cervical vertebrae as they are normally seen on a standardized lateral skull radiograph. Characteristics of the cervical column were classified according to the method of Sandham. The cranial base angle was measured by the angle between nasion sella and sella basion (N-S-Ba) and then compared in the three groups. RESULTS The cranial base angle was increased significantly in the hyperdivergent group and decreased in the hypodivergent group when compared to the normodivergent group patients. However, no significant results were associated regarding the morphology of the cervical column in the three groups. CONCLUSIONS Associations between the cranial base angle and cervical column morphology plays a pivotal role in orthodontics in making the diagnosis of malocclusion and finding out the pattern of growth in vertical direction. A routine examination of the cervical vertebral column area for any deviation in the morphology should be done and checked. These registrations may prove useful in making the diagnosis and finding aetiology especially in the cases of severe skeletal malocclusions like severe open bite and deep bite and those with obstructive disorders like obstructive sleep apnoea or enlarged adenoids.
International Journal of Applied Dental Sciences
The cervical vertebra and its relation to maxilla and mandible is of particular interest to orthodontist due to their correlated developmental and anatomical relationship. The aim of the study is to evaluate and correlate the relationship between cervical vertebral morphology and cervical spine inclination with skeletal sagittal jaw relationship and growth pattern for an individual. Cephalogram of 30 subjects was divided in 3 groups based on ANB angle. All the craniofacial and craniocervical landmarks that are required to be analysed were recorded and it was concluded that class III patients had more posterior inclination of dens axis of CV2 but straighter spine inclination on subsequent arches. EVT/VER values indicated more enhanced curvature of vertical column in class II and class III patients. Morphological assessment of CV1SL & CV1HT revealed significantly less measurements in Class III that among class I and II subjects. CV2BL measurement in class II & III was significantly more than class. CV3Sl was significantly more in class III and CV3BL was significantly less in class II.
Comparative Assessment of Sagittal Maxillo-mandibular Jaw Relationship - A Cephalometric Study
Journal of Oral Health and Community Dentistry, 2012
History is evident that correct assessment of Sagittal Jaw Relationship has always remained the perennial problem in orthodontics. The present study is undertaken to use Sagittal methods for assessing individuals and classifying for Skeletal Class I, Class II and Class III based on Jaw Relationship and to evaluate the reliability of sagittal methods. 200 subjects in the age group of 12 to 18 yrs were selected and were subjected to cephalometric radiography and traced. The sample was divided into skeletal Class I, Class II and Class III on the basis of AXD angle, FABA angle and MM Bisector. Subsequently following angles and linear measurements were measured; Beta angle; AB plane angle; JYD angle; ANB angle; AXB angle; AF - BF and App - Bpp. Result - Consistency could be demonstrated by all the methods assessed by Antero-Posterior jaw relationship. Insignificant difference on influence of growth, age and sex was noted. Angular methods used for assessing jaw relationship such as FABA, ...
The Relation among Different Methods for Assessing the Vertical Jaws Relation 1
2016
Background: Assessment of vertical jaws relation is so important in diagnosing orthodontic cases like the sagittal and horizontal relations. This study aimed to find the relation among different methods used to evaluate the vertical jaws relation. Materials and methods: Fifty students (25 males and 25 females) from the College of Dentistry, University of Baghdad were selected having normal sagittal and horizontal jaws relations and class I dental relation. Digital true lateral cephalometric radiographs were taken for each individual and analyzed using AutoCAD program 2007. Seventeen angular and linear parameters determined the vertical jaws relation were measured for both genders. The relation among these parameters was obtained using Pearson's correlation coefficient test. Results: The mean values of the measured parameters were near to the norms in the original studies. The linear measurements were larger significantly in males than females. SN-PP, SN-MP, SN-OP and the sum of ...
Materials, 2019
The aim of this study was to evaluate the correlation between dental vestibular–palatal inclination changes and the cortical bone remodeling after fixed orthodontic treatment using cone beam computed tomography (CBCT). Twenty-two patients with Angle Class I malocclusion, permanent dentition, and mild to moderate dental crowding were included in the present three-dimensional (3D) analysis. Bone dimensions were evaluated by CBCT scans obtained before and after orthodontic treatment, whereas the torque values were calculated by means of digital models using the 3D VistaDent software. A paired t-test was used to compare the changes between the pretreatment and post-treatment measurements. The correlations between variables were analyzed with linear regression analysis. A significant correlation between torque variations and bone thickness changes was observed for the apical buccal level of the anterior side (P < 0.05). Limited and not significant alveolar bone resorption for the apic...
UI Proceedings on Health and Medicine, 2017
Objective: A concern in fixed appliances orthodontic treatment besides reestablishing the normal occlusion characteristics might cause repositioning of the condyle position in TMJ region. The objective of this research is to find out whether there is a difference of TMJ position in Angle class I malocclusion type 1, 2, 3, 4, and 5 before and after fixed appliances orthodontic treatment. Methods: This research is a pre-and-post design study with analytical statistical approach which compared the TMJ position obtained from tracings 80 lateral cephalometric radiographs before and after fixed appliances orthodontic treatment. Purposive sampling technique was used to determine the sample size in Orthodontic Department of Rumah Sakit Gigi dan Mulut Universitas Padjadjaran from 2009-2015. The data was analyzed by using Kolmogorov-Smirnov Test and paired t-test. Results: This study revealed that the changes of condyle position in Condylion to Vertical T line (horizontally) after orthodontic treatment is not significant (P> 0.05) in Angle class I malocclusion. However, the difference of condyle position in Condylion to TC line (vertically) shows a significant difference (P< 0.05) in Angle class I malocclusion. Conclusion: The distance of the condyle from Condylion to TC line increased after fixed appliances orthodontic treatment for Angle class I malocclusion patients.
The Relation among Different Methods for Assessing the Vertical Jaws Relation
Background: Assessment of vertical jaws relation is so important in diagnosing orthodontic cases like the sagittal and horizontal relations. This study aimed to find the relation among different methods used to evaluate the vertical jaws relation. Materials and methods: Fifty students (25 males and 25 females) from the College of Dentistry, University of Baghdad were selected having normal sagittal and horizontal jaws relations and class I dental relation. Digital true lateral cephalometric radiographs were taken for each individual and analyzed using AutoCAD program 2007. Seventeen angular and linear parameters determined the vertical jaws relation were measured for both genders. The relation among these parameters was obtained using Pearson's correlation coefficient test. Results: The mean values of the measured parameters were near to the norms in the original studies. The linear measurements were larger significantly in males than females. SN-PP, SN-MP, SN-OP and the sum of the posterior angles were significantly higher in females than males. There is clear relation among the measured parameters. Conclusions: Jarabak ratio and sum of posterior angles correlated significantly with each other and with most other parameters. SN plane inclination may give false indication about the vertical relation due to different positions of point Nasion. Like the sagittal jaws relation, only one measurement is not enough for diagnosis the vertical jaws relation.
2015
OBJECTIVE: The morphology of the atlas vertebrae seems to be affected by the head posture, age, congenital anomalies and the skeletal growth pattern. The present study was carried out to assess the variation in the morphology of atlas vertebrae in different vertical skeletal patterns MATERIAL AND METHOD: Cone-beam computed tomography images of 45 adult subjects aged 18 to 35 years were evaluated. Subjects constituted three groups: group 1; average growth pattern; group 2; vertical growth pattern (Skeletal open bite) and group 3; horizontal growth pattern (Skeletal deep bite). Nine linear measurements were used to assess the vertebral morphology. The One way Anova and Tukey Hsd multiple comparison test were used for statistical analysis. RESULTS: The mean inner anteroposterior diameter of the atlas (C1) was significantly greater in the skeletal open bite and the skeletal deep bite group. The height of the atlas dorsal arch was lower in the skeletal open bite subjects. The mean height...
The use of three-dimensional cephalometric references in dentoskeletal symmetry diagnosis
Dental Press Journal of Orthodontics, 2014
OBJECTIVE: The aim of this study is to assess dentoskeletal symmetry in cone-beam computed tomography (CBCT) scans of Brazilian individuals with Angle Class I malocclusion.MATERIAL: A total of 47 patients (22 females and 25 males) aged between 11 and 16 years old (14 years) seen in a private radiology service (CIRO, Goiânia, GO, Brazil) were assessed. All CBCT scans were obtained from January, 2009 to December, 2010. Cephalometric measurements were taken by multiplanar reconstruction (axial, coronal and sagittal) using Vista Dent3DPro 2.0 (Dentsply GAC, New York, USA). Minimum, maximum, mean and standard deviation values were arranged in tables, and Student t-test was used to determine statistical significance (P < 0.05).RESULTS: Data were homogeneous, and differences between the right and left sides were not significant.CONCLUSIONS: Cephalometric measurements of Brazilian individuals with Angle Class I malocclusion can be used to establish facial symmetry and three-dimensional s...