Inclination Of Teeth Research Articles

Changes in the alveolar bone morphology among different patterns of incisor inclination during the alignment phase in orthodontic treatment without premolar extraction.

The present study investigated bone remodelling in the upper and lower incisor regions depending on the inclination pattern during the alignment phase of orthodontic treatment (OT). This prospective clinical study included 71 patients undergoing OT without premolar extraction. Cone beam computed tomography scans were taken before and after the alignment phase and the changes in the inclination, alveolar bone height (ABH) and bone thickness (BT) at levels 2, 3, 4, 6, 8 and 9 mm starting from the cementoenamel junction (CEJ) were determined. Teeth were divided into 'Retroinclination' (lingual crown inclination <0°), 'Proclination-low' (buccal crown inclination between 0° and 5°), or 'Proclination-high' (buccal crown inclination >5°). The alignment phase of OT resulted in ABH loss. The highest ABH loss in the maxilla was observed on the buccal side in the 'Proclination-high' and was 0.71 mm. ABH loss by 1.1 mm was observed in the mandible on the lingual side in the 'Retroinclination' group. The most significant changes in BT by up to 2 mm were observed at levels 6, 8 and 9 mm and these changes exhibited a moderate to strong correlation with the alterations in the inclination of individual incisors. At levels 2, 3 and 4 mm, the highest decrease in BT by up to 0.83 mm was observed on the palatal side of upper incisors in the 'Proclination-high' group. The direction and amount of tooth inclination partially determine changes in the bone parameters during the alignment phase.

THE RELATIONSHIP BETWEEN SKELETAL AND DENTO-ALVEOLAR INDICATORS IN CLASS II MALOCCLUSION

In instances of a distal bite, significant variability exists in the angles of inclination of frontal teeth, potentially impacting the condition of the alveolar bone, soft tissue profile of the face, and the aesthetics of the smile. The aim of this study is to establish correlations between sagittal, vertical, and dento-alveolar cephalometric indicators, and to assess which skeletal cephalometric variables in Class II skeletal patterns influence the variability of changes in the dento-alveolar complex.&#x0D; Materials and methods. A total of 47 cephalograms from patients with II class according to Engle were analyzed. Eighteen cephalometric measurements were performed using the following methods: SNA, SNB, ANB, SN_Ba, SN_Pg, NL_NSL, ML_NSL, NL_ML, Facial axis, PFH_AFH, the sum of Bjork angles, Gonian angle, I1_NL, I1_NA, i1_ML, i1_NB, i1_APg, I1_i1 license program "Audax Ceph" v. 6.6. A total of 846 measurements were made.&#x0D; Results. Class II bite pathology is characterized by prognathism of the upper jaw (increase in the SNA angle) and distal displacement of the lower jaw (decrease in the SNB, SN_Pg angles). Vertical parameters indicate a predominantly neutral type of growth. The average indicators of the inclination of the upper incisors indicate their slight retrusion. Lower incisors are characterized by a vestibular inclination. The most significant correlations of the angle i1_ML with indicators PFH_AFH (Ро=.513**, р=0), ML_NSL (Ро=-.512**, р=0), NL_ML (Ро=-.434**, р=0.002), Bjork (Ро=-.512**, р=0). Significant correlations between the incisal angles of the upper and lower jaws indicate their significant variability. Conclusions. The growth of the facial skeleton in the vertical and sagittal planes is related to the position of the incisors of the upper and lower jaws, which determines the impact on the morphology of bone tissue and facial aesthetics. Considering the interrelationships between parameters is an essential component for achieving successful functional and aesthetic outcomes in orthodontic treatment.

Method to measure faciolingual teeth inclination

This research evaluates the faciolingual inclination of people in Mosul city as a basebracket design for straight wire arch technique (SWA) 50 study models (25females) used aged 12-15 years, they concomitant with six keys of normal 52.that suggested by AndrewsThe data then subjected to statistical evaluation at p&lt;0.05, description of the data(mean SD.. minimum, maximum) also the correlation of all the teeth and comparison for both sexes.)The result show a higher record in lower central and lateral incisors in males (17.0whereas a lowest record found in lower iirst molar in males (-30.0). A high correlation can be seen among anterior teeth and among posterior teeth with each other

Occlusal characteristics in modern humans with tooth agenesis

Non-syndromic permanent tooth agenesis affects a significant proportion of the population, especially if third molars are considered. Although tooth agenesis has been linked to a smaller craniofacial size, reduced facial convexity and a shorter skeletal face, the occlusal characteristics of individuals with tooth agenesis remain largely unexplored. Therefore, this study investigated potential associations between tooth agenesis and metric occlusal traits in 806 individuals (491 with 4.1 missing teeth per subject, including third molars, and 315 without any tooth agenesis). Dentoskeletal morphology was defined through anatomical landmarks on pre-treatment cephalometric radiographs. Multivariate regression models, adjusted for sex and age, showed that tooth agenesis was significantly associated with a reduced overjet, an increased interincisal angle, and shorter upper and lower dental arch lengths, but not with overbite. Moreover, apart from reduced tooth length and dentoalveolar effects, as the number of missing teeth increased the upper front teeth were progressively retruded according to the craniofacial complex and to the face. Thus, tooth agenesis has a substantial influence on dental and occlusal characteristics, as well as on the sagittal position and inclination of anterior teeth. These findings emphasize the necessity for personalized, multidisciplinary approaches in individuals with multiple agenesis to successfully meet treatment goals.

COMPUTER SUPPORT FOR THE DESIGN OF THE HOB CUTTER

The aim of the work is to create a computer program in the 3D CAD system T Flex CAD allowing the creation of parametric models for the design and construction of a modular hob cutter for the selected gearing. The thesis includes the analysis of the problem of hob cutters for the production of spur gearing with an involute profile, the analysis of the initial surface and the shape of the tool cutting edge for the involute surface, the determination of the basic profile of the cutting edge of the hob cutter (geometry of the basic worm, geometry of the cutting edge) and the calculation of the design parameters of the tool. The individual calculations will be programmed in the 3D CAD system T Flex CAD, which will allow to generate a specific 3D model of the hob cutter based on the change of input requirements for the production of a given spur gear (module, engagement angle, tooth inclination angle), with the possibility of displaying the required tool in a 2D view in its base, normal and side planes, which will be in the form of a standard technical drawing. This paper presents the preparation (unification calculations, introduction) before the final version of the computer program for the creation of the parametric tool models.

Correlation between Cleft Width and Adjacent Teeth Inclination in Patients with Unilateral Cleft Lip and Palate Using CBCT: A Retrospective Study.

To evaluate buccolingual and mesiodistal inclination of cleft-adjacent maxillary permanent central incisors (U1) and canines (U3) in patients with unilateral cleft lip and palate (UCLP) in the late mixed dentition and to investigate the correlation between the alveolar cleft width and cleft-adjacent teeth inclination using cone beam computed tomography (CBCT). Observational cross-sectional retrospective study. Department of Orthodontics, Hama University Dental School. 32 patients with UCLP (22 boys, 10 girls; mean age = 10.53 ± 1.51 years). Buccolingual and mesiodistal inclination of maxillary central incisors and canines were measured on both sides. Then, the cleft and non-cleft sides were compared using the Wilcoxon signed-rank test. Pearson's correlation was used to explore the association between the alveolar cleft width and cleft-adjacent U1 and U3 buccolingual and mesiodistal inclination. The cleft-adjacent central incisors were significantly inclined lingually and distally compared with their non-cleft antimeres (P = .003, P < .001, respectively). The cleft-adjacent canines were significantly inclined buccally and mesially compared with their non-cleft antimeres (P < .001, for both). A positive correlation was found between the buccolingual inclination of cleft-adjacent U1 and the alveolar cleft width (r = 0.49, P = .004). Patients with UCLP demonstrated a significant lingual and distal inclination of cleft-adjacent U1 and a significant buccal and mesial inclination of cleft-adjacent U3. The buccolingual inclination of cleft-adjacent U1 tends to increase with increasing the alveolar cleft width; however, the correlation was weak.

Принципи планування препарування зубів під незнімні конструкції зубних протезів за аналізом конусно-променевої комп’ютерної діагностики

Introduction. The relevance of the study is to develop a plan for the preparation of teeth for fixed dentures based on the analysis of cone beam computed tomography (CBCT) to prevent complications. The aim of the study. To develop the basic principles of planning the preparation of different groups of teeth for fixed dentures based on the analysis of cone beam computed tomography. Materials and methods. An analysis of the planning of orthopedic treatment of fixed dentures on the basis of CBCT examination of the teeth of the upper and lower jaws in 26 patients with disorders of the anatomical structure of the crown part of the teeth and their placement in the dentition, defects of the crown part of the teeth, tremas and diastemas, and 42 patients with small and medium defects of the dentition was carried out. The examination was performed on an X-ray machine with the function of a Veraviewepocs 3D R100 P computed tomography scanner. Results of the study. The analysis of examinations of the anatomical structure of different groups of teeth using CBCT showed the possibility of preliminary determining the safe areas of the predicted volume of tissue preparation of the crown part of the tooth for fixed dentures, correctly modelling the future slope of the prepared tooth walls with the condition of a tight fit of the artificial crown in the cervical region of the tooth and the possibility of preparing a tooth with a ledge while maintaining its vitality. It was proved that using the software function “Measurements and Overlays”, “Measure angle” in the lateral and frontal projections, it is possible to selectively shift the slope and optimally move the lines (of the future preparation) on the medial, distal, lingual, vestibular sides of the teeth (maintaining their parallelism with an accuracy of 0.01 degrees) and solve possible options for the predicted volumetric preparation of the vital teeth for fixed dentures. The criterion for choosing the predicted depth of preparation of the tissues of the crown part of the vital teeth in the cervical region from the vestibular, oral, medial and distal sides, without a ledge or using the appropriate depth of the ledge, is the thickness of the dentin to the pulp chamber of the tooth in the axial plane, which was measured with the “Ruler” function with an accuracy up to 0.01 mm. Conclusions. The use of the obtained CBCT data of the anatomical structure of the teeth will allow the following: to predict the possibility of preparation of the vital teeth for fixed dentures, to predict the volume of preparation of the crown part of the tooth, taking into account its individual anatomical structure and tooth inclination, to optimally choose the method of preparation – without a ledge or using the appropriate depth of the ledge, to prevent complications from the tooth pulp and marginal periodontium, and to improve the quality of orthopedic treatment of fixed dentures. Key words: cone beam computed tomography, periodontium, defects of teeth and dentition, abutment teeth, orthopedic structures, fixed bridges, tooth preparation.

Diagnostic accuracy of conventional orthodontic radiographic modalities and cone-beam computed tomography for localization of impacted maxillary canine teeth.

Orthodontic treatment planning for an impacted canine tooth requires accurate information about its position. The aim of this study was to compare the diagnostic accuracy of two conventional orthodontic radiographic modalities with cone-beam computed tomography (CBCT) for localization of impacted maxillary canine teeth. Panoramic radiographs, lateral cephalograms, and CBCT scans of 30 patients with unilaterally impacted maxillary canine teeth were retrieved from the archives. Eight expert orthodontists evaluated the parameters related to the location of impacted canine teeth by using panoramic radiographs and lateral cephalograms of patients. After 4 weeks, the same parameters were evaluated on CBCT scans of patients. The diagnostic accuracy of conventional modalities and CBCT was compared with each other and also with the gold standard. The conventional radiographic modalities and CBCT had similar accuracy for assessment of the overall inclination (p = 0.11), apex morphology (p = 0.18), and mesiodistal position of the apex (p = 0.12). CBCT had significantly higher accuracy for determination of incisal tip location (p = 0.001), labiopalatal (p = 0.001) and vertical (p = 0.01) position of the crown tip, minimum bone thickness covering the crown (p = 0.001), and root resorption of the adjacent tooth (p = 0.001). The combination of panoramic radiographs and lateral cephalograms was sufficiently accurate to assess some diagnostic parameters such as overall inclination, apex morphology, and mesiodistal apex location of impacted canine teeth.

Fabrication of Distal Extension Removable Partial Denture with Surveyed Crown and Altered Cast Technique: A Case Report

Support and stability for a Removable Partial Denture (RPD) are difficult to achieve in a distal extension edentulous ridge and are even more compromised in reduced dentition. The combination of the altered cast technique and milled crown in removable partial denture fabrication would greatly enhance support by redistributing the load more effectively. However, it is not routinely practiced due to the complexity of the treatment and the lack of emphasis in dental curriculum. In the present case of a 54-year-old male, despite several attempts at wearing the denture, the patient was unable to tolerate it. The atrophic mandibular ridge and poor inclination of the abutment tooth seemed to be complicating factors. Therefore, the prosthesis required some modifications. The present case report highlights the Applegate altered cast technique, which can be deployed with a milled crown, including the clinical and laboratory stages involved. This might help to overcome the problems encountered with distal end saddle dentures, making them more tolerable to patients.

Tratamento ortodôntico de um paciente com necessidades especiais: um relato de caso

ABSTRACT This report presents the case of an adult patient with mental and intellectual limitations, whose main complaint was dental aesthetics. Dental treatment was performed at the Piracicaba Dental School and approved by the Ethics Committee (CAAE: 65752322.2.0000.5418). Clinically, the patient had inadequacies in the dental arrangement, with periodontal involvement that put the dental elements at risk. In intraoral clinical aspects, the deficiency was identified as maxillary atresia. The buccolingual inclination of the mandibular anterior teeth highlighted the severe crowding and anterior crossing of these teeth. Dental treatment was carried out aiming at the remission of periodontal and orthodontic problems in an integrated manner and with approaches that allowed greater interaction, participation, and patient compliance during treatment. Supra and subgingival scrapings and extraction of the upper left lateral incisor were performed. After three months of periodontal treatment, orthodontic treatment was started with fixed orthodontic appliances. The main objective was to level and align the teeth in both arches to achieve better aesthetic and functional conditions. Due to the COVID-19 pandemic, treatment has been discontinued. This resulted in the regression of the results obtained, including regarding self-care. People with disabilities require dental care with specific strategies for their needs, which must be carried out by a multidisciplinary team. Despite the access limitation imposed by the pandemic, the patient reestablished his motivation to restart treatment, which was facilitated by the bond of trust established between him and the team.

Оцінка клініко-антропометричних та рентгенологічних показників у пацієнтів із затримкою прорізування зубів фронтальної групи верхньої щелепи

Introduction. Delayed eruption of teeth is an urgent orthodontic problem, but in most cases, it is detected incidentally during a routine dental examination. It is therefore extremely important that dentists diagnose this pathology as early as possible, as early intervention can help prevent a variety of complications. The treatment of delayed eruption requires multidisciplinary cooperation between paediatric dentists, orthodontists, surgeons and orthopaedists. Aim. To evaluate clinical, anthropometric, and radiological parameters in children aged 7 to 14 years who have delayed eruption of upper front teeth. Material and Methods. The study was conducted on Ukrainians aged 7 to 14 years who had delayed eruption of teeth. The patients were divided into 2 groups: Group I (49 (44.9%)) included children aged 7 to 9 years with early mixed occlusion; Group II (60 (55.1%)) was made of individuals aged 10 to 14 years who had the final stage of mixed occlusion. The control group consisted of 18 individuals who had their oral cavities health improved and had normal occlusion. After a thorough history taking and external examination, we conducted the following studies: clinical, anthropometric, radiological, and statistical. Results. At the age of 7 to 9, boys with delayed eruption of teeth (DET) outnumbered girls, whereas at the age of 10 to14, girls with delayed eruption significantly outnumbered boys. Delayed eruption of maxillary canines was found in 80% of children aged 10 to14 years. It was revealed that the main causes of delayed eruption in children aged 7-9 years were trauma to the previous deciduous teeth (65.3%) and early extraction of the previous deciduous tooth (73.5%). Among those aged 10 to 14 years, a trauma to the primary teeth was found in 16.7% and early extraction in 73.3% of paediatric patients. As the children with delayed eruption of upper frontal teeth grew older, we observed considerable changes in the size of the jaws with inadequate space for eruption. The children had a predominantly vestibular position of the teeth (44%). We found tooth inclination angles of more than 15° in 52.3% of the children in the study groups. Conclusion. Based on the analysis of the data obtained from the medical history, clinical, anthropometric and radiographic examinations, it can be assumed that with increasing age, the number of teeth with an unfavourable position increases, which prevents their successful eruption into the dental arch. The lack of space for eruption is particularly detrimental to canines. Key words: delayed eruption of teeth, anthropometric examination, radiography, CBCT, dental trauma, mesiodistal shortening of the dental arch.

Correction of Anterior Crossbite, Using Removable Appliances in Mixed Dentition: 5-Year Follow-Up

The anterior crossbite (ACB) is a malocclusion where the upper anterior teeth are occluding lingually with respect to the lower anterior teeth. Moyers describes anterior crossbites as dental malocclusions resulting from abnormal axial inclinations of the anterior teeth. This type of malocclusion can be dental, functional or skeletal and can occur in the primary, mixed and second dentition. Diagnosis is made using diagnostic aids. While the treatment was carried out through interceptive orthodontics, with the use of different removable appliances. The objective of the study is to present the diagnosis and treatment for 5 years with the use of removable appliances. The results were favorable, being able to uncross the bite in 4 months, it was maintained throughout the dental replacement. One of the conclusions reached is that the treatment time is slightly longer since the use of preventive and interceptive orthodontics takes more time because these treatments are performed during the growth of the patients.

FIVE-YEAR RADIOGRAPHIC FOLLOW-UP OF ASYMPTOMATIC IMPACTED THIRD MOLAR TEETH WITH COMPLETED APICAL ROOT DEVELOPMENT

Third molar teeth can stay impacted due to systemic factors, space deficiency, pathology or an anatomical obstacle. The positions, angles, follicle sizes, and impaction statuses of impacted third molars can change over time. The purpose of this study is to investigate changes in the position, inclination, angle, and follicular width of impacted third molars at the end of a 5-year follow-up on panoramic radiographs. Retrospective analyses of a total of 98 impacted third molar teeth were carried out on panoramic radiographs taken at 5-year intervals for 31 patients who presented to the Department of Oral and Maxillofacial Radiology at Faculty of Dentistry for various reasons between 2013 and 2021. The mean angle of the examined impacted third molars with the occlusal plane was 26.725±27.31° at the beginning of the 5-year follow-up and 26.399±28.46° at the end of the follow-up. There was a 5° angular change(inclination) in 4(8.2%) impacted molars. In the examinations of the panoramic radiographs taken at 5-year intervals, no pathologic change around any impacted third molar or resorption in neighboring teeth was observed. There were inclination changes in 2(4%) of the impacted molars and position changes in 11(22.4%). The changes may be occur in the position, inclination, angle, and follicular width of asymptomatic impacted teeth in time. It is important that asymptomatic impacted teeth can be followed radiographically to evaluate the effects of changes in position, inclination, angle and follicle width over time on the impacted tooth and surrounding tissues and to prevent complications that may occur after a possible impacted third molar extraction.

Prevalence and extent of Alveolar dehiscence and fenestration in Class I hyperdivergent subjects with different buccolingual inclinations of maxillary molar teeth

Buccolingual position of teeth could affect the prevalence of alveolar bone defects. Presence of alveolar defects may have a deleterious effect on orthodontic treatment. The aim was to assess the prevalence and extent of dehiscence and fenestration in Class I hyperdivergent subjects and correlate it with buccolingual inclinations(BL) of maxillary first molar teeth. Methods: This retrospective study involved 80 CBCTs of class I hyperdivergent subjects divided into two groups - group A (n=33) buccolingual inclination &gt;9º and group B (n=47) buccolingual inclination &lt;9º. Prevalence and extent of alveolar bone dehiscence and fenestrations were measured in CBCTs using OSIRIX Lite software. Descriptive statistics, Mann Whitney U test and Spearman correlation were done for evaluating intergroup differences and correlation with Buccolingual inclination. Results: Overall prevalence of dehiscence and fenestration in maxillary first molars was 60.95% and 5% respectively. In the buccal alveolar bone, prevalence of dehiscence was highest in group A (84.6%) for 16 and in the lingual alveolar bone prevalence of dehiscence was highest in group B (71.4%) for 26 . On intergroup comparison, the extent of lingual alveolar bone dehiscence (26) in group B was significantly higher (p value &lt;0.05) than in group A. No significant correlation between the extent of dehiscence and fenestration with buccolingual inclination of molar teeth was noted. Conclusion: Molar teeth with BL inclinations of more than 9º had higher prevalence of dehiscence on the buccal side and molar teeth with BL inclinations less than 9 degrees had more dehiscence on the lingual side. But no significant correlation of BL inclination with prevalence and extent of dehiscence and fenestration was noted.

Three-dimensional analysis of posterior tooth inclinations in transverse and sagittal relationships: A cross-sectional study

To compare tooth inclinations in different sagittal skeletal patterns and transverse maxillary relationships three-dimensionally. A cross-sectional study carried out with 132 three-dimensional digital models in the complete permanent dentition divided into six groups (n=22); three groups with maxillary atresia: G1- skeletal class I, G2- skeletal class II and G3-skeletal class III; three groups without maxillary atresia: G4- skeletal class I; G5- skeletal class II and G6- skeletal class III. The comparison between the skeletal pattern was performed by the non-parametric tests of Kruskal Wallis and Dunn and between the groups by the non-parametric test of Mann Whitney. Subjects with skeletal class II and maxillary atresia had a greater lingual inclination of the maxillary teeth than those with class I and III; Subjects with skeletal class II without atresia had a less lingual inclination of the mandibular molars than the other classes (p<0.05). The maxillary premolars showed no variation in dental inclination with atresia, independent of the skeletal class in G1, G2, and G3 (p>0.05). The mandibular premolars showed that the groups without atresia G4, G5, and G6 presented no significant difference (p>0.05). Lower premolars in skeletal class III malocclusion individuals with atresia had a more negative inclination than the others. There is a difference in the inclination of posterior teeth between individuals with and without maxillary atresia and skeletal classes I, II, and III.

Justification of the Choice of Parameters for the Gear Power Skiving Operation Based on Computer Simulation

Abstract The paper presents the results of modelling and investigation of the gear cutting process using the power skiving method. The investigations are based on the developed geometrical model of undeformed chips. The approach is based on the original method of forming an integral three-dimensional model on the basis of discrete cross-sections of tool tooth in their successive positions on the cutting path, taking into account the shape and size of the gap previously formed by this tooth. The formulae for calculating the cutting force and the forces acting on the work gear and tool are derived as a function of the angular position of the cutter. The dependence of this force on the angle of tool shaft setting and the angle of inclination of gear teeth is studied. The formulae take into account how the cutting intensity changes due to the peculiarities of the kinematics of power skiving technology and the influence of the actual geometric parameters of the tool on the cutting force. Based on the obtained dependencies, a methodology has been developed for the selection of the axial feed rate and spindle set angle to ensure a compromise between the required productivity and the accuracy of the gear profile.

Assessment of early dental arch growth modification with removable maxillary expansion by cone-beam computed tomography and lateral cephalometric radiographs: a retrospective study

BackgroundThis study evaluated the skeletal and dental changes of patients brought by early removable maxillary expansion (ERME) treatment to explore the clinical treatment effect of ERME on early dental arch growth modification.MethodsSubject children aged 6–10 years with a maxillary transverse deficiency received ERME treatment, cone-beam computed tomography (CBCT) and lateral cephalometric radiographs were measured before and after treatment, and statistical differences in the measured items were evaluated with corresponding statistical methods to explore the skeletal and dental changes.ResultsAfter ERME treatment, there was a statistical increase in the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. A buccal inclination of the maxillary alveolar bone and a buccal inclination and buccal movement in the alveolar bone of maxillary first molars were found. The maxillary skeletal expansion was statistically greater than the dental expansion. Increases in the mandibular alveolar bone arch width and dental arch width happened after treatment. A decrease in angle ANB and an increase in Ptm-A, U1-SN, U1-PP, L1-MP, and L6-MP were found after treatment. No statistical changes in the growth pattern-related measured items were observed.ConclusionsERME could expand the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. The maxillary skeletal expansion was greater than the dental expansion. Secondary increases in the mandibular alveolar bone and dental arch widths would happen after ERME. ERME would result in a mandibular advancement, a labial inclination of maxillary anterior teeth, and an increase of maxillary sagittal length, and would not change the patient’s growth pattern.Trial registrationThis study was approved by the Institutional Review Board of the West China Hospital of Stomatology, Sichuan University. (WCHSIRB-D-2020–446).

Comparison of linear and angular measurements in mandibular symphyseal region using lateral cephalometric and cone beam CT images

AbstractAimTo compare the linear and angular measurements of the mandibular symphyseal region using lateral cephalometric (LC) and cone beam computed tomography (CBCT) images.Materials and MethodsOne hundred patients justifying both LC and CBCT exposures were included. Both lateral cephalometric and CBCT images of the patients were used for angular and linear measurements. Angular measurements included vestibular concavity and lingual and tooth inclination angles. Vestibular and lingual cortical bone and total bone thickness measurements were obtained for the comparison of linear measurements. Three radiologists performed the measurements on 200 images. Comparison of the measurements and the imaging methods were done using paired‐ and Wilcoxon t‐tests. Inter‐observer reliability was evaluated with the intra‐class correlation coefficient (ICC).ResultsA significant difference was observed between measurements of two imaging methods for tooth inclination and vestibular concavity angles; however, no difference was found between LC and CBCT measurements for lingual inclination angle (p &gt; 0.05). Vestibular cortical bone and total bone thickness measurements showed a significant difference (p &lt; 0.05), whereas no difference was obtained in lingual bone thickness measurements of two imaging methods (p &gt; 0.05).ConclusionCBCT imaging is recommended in selected patients where recipient bone or bone augmentation site(s) reveal suspect in clinical examination and lateral cephalometric imaging may not reveal the true anatomic structure and relationships.

Evaluation of First Molar Buccolingual Angulations and Dental Arch Parameters in Adolescents with Bilateral Posterior Crossbite.

This study aimed to compare the maxillary and mandibular transverse dental arch widths and buccolingual inclinations of the molar teeth in patients with and without bilateral posterior crossbite (BPC) divided into different age groups. The study included dental models from 120 patients (age: 12-18 years), including 60 with BPC (32 boys and 28 girls) and 60 without BPC (controls; 30 boys and 30 girls), who were divided into three age groups (12-14, 14-16, and 16-18 years). The centroid and lingual transverse arch widths, dental arch perimeters, dental arch depths, and buccolingual angulation of the molar teeth in the maxillary and mandibular regions were evaluated using scanned three-dimensional dental models. Dental arch parameters and buccolingual molar angulation did not significantly differ between the different age groups in either the patients with BPC or the controls (p>0.05). However, several dental arch width parameters differed significantly between sexes in both groups, with higher values in boys than in girls (p<0.05). The difference in the upper and lower molar buccolingual angulation between patients with BPC and controls was greater at the age of 16-18 years than the age of 12-14 years (p<0.05). Patients with BPC have smaller maxillary dental arch widths and larger mandibular intermolar widths than those without BPC. The difference in the molar buccolingual angulation between them increases with advancing age.

COMPARING ARCH WIDTH, ALVEOLAR WIDTH ANDBUCCOLINGUAL INCLINATION OF POSTERIOR TEETH IN SUBJECTS WITH CLASS IANDCLASS II MALOCCLUSION

Aim: The aim of this study was to compare the arch width, alveolar width and buccolingual inclination of posterior teeth between Class I and Class II Div 1 malocclusion subjects. Materials and method: A sample of120 subjects (60 males and 60 females) in the age group of 16-19 years with Class I and Class II Div 1 malocclusion were chosen and arch width, alveolar width and buccolingual inclination of posterior teeth were measured and compared between the groups. Result: The maxillary posterior teeth showed more palatal inclination in Class II Div 1 malocclusion when compared with Class I group. Conclusion:Transverse discrepancy in Class II Div 1 might be due to more palatal inclination of maxillary posterior teeth rather than arch width and alveolar width. Hence slow maxillary expansion should be preferred for correcting the palatal inclination rather than rapid palatal expansion.