Age Estimation Using Panoramic Radiography and Lateral Cephalogram—A Comparative Study

Context: Age estimation allows the identification of living individuals, dead victims and estimation of age in children using maxillofacial radiographs. Aim: To compare age estimation by mandibular third molar developmental stages using modified Demirjian’s method on OPG with age estimation by mandibular linear dimensions on lateral cephalogram. Setting and Design: A total of 200 randomly selected subjects (100 males and 100 females), with age range from 9 to 20 years, and 200 Digital Orthopantomograms and 200 Digital Lateral Cephalograms were utilized for the study. Methods and Material: Radiographs were taken with Kodak 8000C Digital Panoramic and Cephalometric machine operating at 60–90 kvp, with exposure time of 8–18 s at 2–15 mA, with an inbuilt magnification factor. A flat screen Compaq TFT?LCD monitor was used to view the OPG images. Linear mandibular dimensional measurements were made on each Digital Lateral Cephalogram using Trophy Dicom Software. Statistical Analysis Used: Regression analysis and regression coefficient for establishing gender?specific equation were observed. Evaluation of results and statistical analysis was carried by using Student’s ‘t’ test. For all test, ‘P’ value of 0.05 or less was utilized for measuring the degree of significance. Intra?observer variability was detected using reliability analysis. Results: The accuracy of age estimation by OPG was 93.8% and by lateral cephalogram was 79.7%. Conclusion: The OPG analysis is more reliable than the cephalometric parameters.

A Radiographic Assessment of Morphological Diversity of Soft Palate in Darbhanga (Bihar) Population: An Original Research

Introduction: Soft palate (velar) plays an important function in head and neck region. Its diverse morphology is implicated invarious diseases.Aims and Objectives: The aim of this study was to evaluate the morphological variants of soft palate in each group of normal,oral submucous fibrosis, and obstructive sleep apnea (OSA) patients. The objective of this study was to evaluate the morphologicvariations of velar using digital lateral cephalogram.Materials and Methods: This study was conducted in the department of oral medicine and radiology and department of publichealth dentistry. Three groups were made, each of 50 patients. The soft palate morphology was evaluated according to theclassification given by You et al.Statistical Analysis: The collected data were subsequently processed and analyzed using the SPSS statistical packageversion 17.Results: We found that most common soft palate morphology in Group I was rat-tail, whereas in Group II and Group III, themost common morphology was leaf shape.Conclusion: Soft palate has different morphology. It may help in successful functional and structural repair in cleft palate casesand shed some light toward the cause of OSA and related disorders.

A Comparative Study on Measurement of Maxillary Occlusal Cant Obtained through Facebow Transfer and Using Lateral CEPH.: An in vivo Study

Purpose: The purpose of the study was tocompare measurements of maxillary occlusal cant obtained through facebow transfer and through lateral cephalogram.Method:40 subjects were included in this study according to inclusion and exclusion criteria and divided into two groups: dentulous and edentulous. For edentulous subjects, all the steps of complete denture fabrication were carried out and finished dentures weredelivered. Alginate impressions were now made for all the subjects (with complete denture worn in edentulous cases) for both upper and lower arches. The study was conducted in two parts. Facebow transfer was done next and casts were mounted. In first partof the study, sagittal inclination was measured after facebow transfer. After mounting of the casts, four points were marked to measure the inclination of the occlusal plane. In second part, cephalometric evaluation of occlusal plane and Frankfurt horizontal plane was carried out. Angle between Frankfurt horizontal plane and the occlusal plane was maxillary occlusal cant. which was evaluated by tracing.Paired t test was used to compare mean facebow values and lateral ceph values in edentulous subjects. Intergroup comparison between lateral ceph and mean facebow values between dentulous and edentulous subjects was evaluated using independent t test.Results:Facebow measurements gave comparatively higher values in both dentulous and edentulous patients and are subjected to less variation as compared to the lateral cephalogram values p<0.0001.Conclusion:The occlusal plane angle of lateral cephalogram was found to be significantly different from angle obtained through facebow transfe

Association Of Impacted Third Molars With Facial Growth Patterns Among Adult Indian Patients - A Retrospective Study

Introduction: The third molar (3M) varies more than other molars in terms of shape, size, timing of eruption, and tendencytoward impaction. Hence, studies need to be carried out to clarify the association of the various patterns of facial growth withmandibular 3M impaction.Purpose: The purpose of this study is to relate the level of impaction of mandibular 3Ms and their inclinations to various patternsof facial growth among Indian patients.Materials and Methods: A total of 207 lateral cephalograms and optic pathway gliomas (OPGs) of patients were obtainedfrom NISSAN Radiological and Diagnostic Centre. The OPGs were analyzed by a single examiner as per: (1) Angulations(using Quek’s analysis - beta angle, 2003). (2) Depth of 3Ms. The lateral cephalograms were assessed by a single examinerusing: (1) Down’s analysis. (2) Beta angle. (3)Jarabak’s ratio. (4) Bjork’s analysis.The subjects were further classified into skeletal Class I, II, and III as well as into horizontal, vertical, and normal growth patterns.The final study data were subjected to a Pearson correlation test to check the association between the 3M impactions andvarious angles. The values found significant were coded into ordinate data and Kendall’s Tau-B Test was done.Results: Statistically, significant correlation was found between depth of impacted mandibular 3Ms and facial angle, Y-axis,cant of occlusion, angle of convexity, and gonial angle.Conclusion: Greater incidence of 3Ms was found to be at position B and C in Class II patients as compared to Class I and IIIpatients. Furthermore, patients showing vertical growth pattern were found to have increased percentage of mandibular 3Mimpactions.

Benefits of lateral cephalogram during landmark identification on posteroanterior cephalograms / 대한치과교정학회지

OBJECTIVE: Precise identification of landmarks on posteroanterior (PA) cephalograms is necessary when evaluating lateral problems such as facial asymmetry. The aim of the present study was to investigate whether the use of lateral (LA) cephalograms can reduce errors in landmark identification on PA cephalograms. METHODS: Five examiners identified 16 landmarks (Cg, N, ANS, GT, Me, RO, Lo, FM, Z, Or, Zyg, Cd, NC, Ms, M, and Ag) on 32 PA cephalograms with and without LA cephalograms at the same time. The positions of the landmarks were recorded and saved in the horizontal and vertical direction. The mean errors and standard deviation of landmarks location according to the use of LA cephalograms were compared for each landmark. RESULTS: Relatively small errors were found for ANS, Me, Ms, and Ag, while relatively large errors were found for N, GT, Z, Or, and Cd. No significant difference was found between the horizontal and vertical errors for Z and Or, while large vertical errors were found for N, GT, and Cd. The value of identification error was lower when the landmarks were identified using LA cephalograms. Statistically significant error reductions were found at N and Cd with LA cephalograms, especially in the vertical direction. CONCLUSIONS: The use of LA cephalograms during identification of landmarks on PA cephalograms could help reduce identification errors.

Geometric morphometric analysis of malocclusion on lateral cephalograms in Malaysian population / 대한해부학회지

Características esqueletales para la determinación cualitativa del biotipo facial en telerradiografía lateral: Estudio Piloto / Skeletal characteristics for subjective determination of facial type in cephalometric x-ray: a pilot study

RESUMEN: Objetivo: Determinar parámetros visuales sencillos para la evaluación de características esqueletales relacionadas con el biotipo facial en una telerradiografía lateral. Material y método: Estudio transversal descriptivo. Se confeccionó una guía visual impresa acerca de ocho características morfológicas del esqueleto facial visibles en la telerradiografía de perfil. Ésta fue entregada a un grupo de 69 estudiantes de Odontología de 5º año sin estudios previos en cefalometría, quienes la analizaron durante 10 minutos. Inmediatamente se les mostraron una serie de telerradiografías, y se les pidió que evaluaran las 8 características a través de una serie de opciones presentadas en una escala visual que se correspondía con la guía estudiada. Las respuestas fueron registradas utilizando un sistema digital de cliqueras. Los datos fueron analizados con el método Rasch para determinar la dificultad de los ítems, estableciéndose el grado de dificultad a través del Logit. Resultados: Los estudiantes lograron identificar y graduar sin dificultad 5 de las 8 características presentadas. Éstas fueron: Proyección del mentón (-2,49), Divergencia facial (-2,85), Ancho de la rama mandibular (-1,97), Escotadura sigmoidea (-0,96) y Relación de la rama con el cuerpo mandibular (-0,06). Conclusión: Se determinó que hay 5 características de la morfología ósea facial relacionadas con el biotipo que se pueden identificar y graduar sin dificultad por estudiantes de pregrado de odontología. Ésta información podría ser utilizada para construir una escala sencilla de identificación del biotipo facial.

ABSTRACT: Aim: Determine simple visual parameters to evaluate skeletal characteristics related to facial types in lateral teleradiographs. Materials and Methods: Descriptive cross-sectional study. A printed visual guideline about the eight visible morphological characteristics of the facial skeleton in cephalometric x-rays was created. The guideline was given to 69 undergraduate dental students (fifth year) without previous studies in cephalometric to analyze it for 10 minutes. Immediately after, they were shown a series of teleradiographs and were asked to evaluate 8 characteristics through a series of options presented in a visual scale according to the guideline. The answers were recorded through a digital audience response system (clickers). The data obtained were analyzed with the Rasch method to assess each item level of difficulty, establishing the Logit number for each one. Results: The students identified and graded without difficulty 5 of the 8 characteristics. These were: Chin projection (-2.49), Facial divergence (-2.85), Mandibular ramus width (-1.97), Sigmoid notch (-0.96) and Mandibular body with ramus relationship (-0.06). Conclusions: Five facial osseous morphological characteristics related to the facial types can be identified and graded without difficulty by undergraduate dental students. This information may be used to create a facial type identification scale.

Pharyngeal Airway Dimensions in Skeletal Class II Young Adolescents : Cephalometric Study / 대한소아치과학회지

This study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of the patients with skeletal class II division 1 or division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group (79 for pre-peak, 40 for peak, 40 for post-peak). Total 159 lateral cephalograms (70 for skeletal class I, 51 for skeletal class II, division 1, and 38 for skeletal class II, division 2) were selected.The growth of anteroposterior dimension of the pharyngeal airway were statistically significant among growth periods. The dimension for the nasopharyngeal and oropharyngeal airway space was the smallest in the division 1 skeletal class II group followed by class II division 2 and skeletal class I.

Lateral Cephalometric Measurements of Class I Malocclusion Patients with Uncertainty / 대한소아치과학회지

The aim of this study was to obtain the traceability of the software used to analyze lateral cephalometry and to calculate the uncertainty of the measurements. Furthermore, this study aimed to provide a basis for obtaining standard references for measurement values for orthodontic treatment in children.Cephalometric data were collected from 100 children diagnosed with class I malocclusion between the ages 6 to 13 years who visited the pediatric dentist at Seoul National University Dental Hospital. To ensure traceability, a phantom device was created. Correction values were calculated by measuring the length and angle of the phantom device using the software. Type A uncertainty was calculated by obtaining the standard deviation of cephalometric measurements of 100 persons and the standard error of repeated measurements. Determination of the type B uncertainty was induced by minimum resolution and the position of the head. Using these, the combined standard uncertainty was obtained and the expanded uncertainty was calculated.The results of this study confirm that the currently used software has high accuracy and reliability. Furthermore, the uncertainty of orthodontic measurements in Korean children aged 6 to 13 years was calculated, and distribution range for class I malocclusion with 95% confidence interval was suggested.

Evaluation of Upper Airway Depth with Different Anteroposterior Skeletal Patterns in Children / 대한소아치과학회지

The respiratory function is relevant to the craniofacial growth and orthodontic diagnosis. The size of the pharyngeal airway was measured in lateral cephalometric view in children visited Kyung Hee University Hospital from January 2015 to August 2017. A total of 74 healthy children (36 boys and 38 girls) aged 7 - 11 years (mean, 8.5 years) with a normodivergent facial pattern were divided into three groups according to anteroposterior jaw relation measuring A point-Nasion-B point (ANB) angle. Lateral cephalometric data were used to measure the airway dimensions. The dimensions of the middle airway were significantly lower, reducing the upper airway space, in large ANB angle group than in other children, suggesting that children with large ANB angle have narrower airway space than others.

Difference in lateral cephalogram of the male patients with Uygur and Han OSAHS / 临床耳鼻咽喉头颈外科杂志

Objective:To investigate the difference of lateral cephalogram, PSG, BMI in Uygur and Han OSAHS male patients. Method:OSAHS male patients with 33 Uygur cases and 42 Han cases,30 normal Uygur cases and 36 normal Han cases were taken as control.Lateral cephalogram of upright position in waking state, then comparecraniofacial strcture parameters and PSG dates, etc. Result:Patients in OSAHS group and normal group had significant differences in the MP-H, PAS, PNS-P, BMI (P<0.05), the Uygur healthy men and Uygur male OSAHS patients had significant difference in the ANB° (P<0.05). The difference was statistically significant in PNS-P, MP-H and BMI in Uygur and Han OSAHS male patients (P<0.05). Conclusion:The differences in airway plane, hyoid position and length of soft palate and weight were significantly different between healthy men and OSAHS men. Han OSAHS male patients and Uygur male patients had significant differences in Hyoid position, length of the soft palate and weight. Lateral cephalogram can judge blocking site of upper airway and provide opration plan.

Dimensional change in soft tissues with complete dental prosthesis and its effect on airway space and natural head position.

Background: Insertion of the intraoral prosthesis causes deflection of the tongue, soft palate affecting the patency of the airway. Aims: To evaluate the cephalometric soft tissue variation in tongue, soft palate, and its effect on posterior airway space in edentulous patients with the insertion of the denture. Settings and Design: Randomized controlled trial. Materials and Methods: Complete denture (CD) prosthesis was fabricated for first time denture wearers comprising 22 males and 18 females within the age range of 50–65 years. Lateral skull radiographs were taken for each of the subjects in their resting position without CDs (T0), with CDs (T1) at least 1‑week postinsertion and after 6 months of usage (T2), respectively. The reference points, lines, and angles on the cephalometric films were used to evaluate the position or inclination of the head, variations in tongue position and length, the changes in the anteroposterior dimension of the soft palate, and posterior airway space variations. Intra‑investigator error variance was not found to be statistically significant (P < 0.05). Statistical Analysis Used: Using Statistical Package for the Social Sciences (SPSS) v16.0 the significant difference in the paired samples (without CD and with CD) was found using the paired t‑test. The probability value P = 0.05 is considered as a significant level. Results: On comparison of T1 and T0, the heads were more extended with the downward position of the tongue with an increase in its length and the posterior airway space was decreased in T1. Significant differences in values were not observed between T1 and T2. Conclusions: With CDs, the change in airway space was related to alteration in soft palate and tongue dimension. There were no changes in dimension at 6 months follow‑up.

Relationships between mandibular second molar calcification stage and cervical vertebrae maturity / 实用口腔医学杂志

Objective:To investigate the relationship between mandibular second molar calcification stage and cervical vertebrae maturity.Methods:Samples were derived from panoramic radiographs and lateral cephalograms of 500 subjects (223 males and 277 females)aged 9 to 18 years.Demirjian Index(DI)and cervical vertebrae maturation indicators(CVMI)were used for the evaluation of dental and skeletal maturity.Results:A significantly association was found between DI and CVMI(P <0.001).DI stage E was associated with CVMI Ⅱ(pre-peak of pubertal growth spurt).DI stages F and G was associated with CVMI Ⅲ and Ⅳ(peak of pu-bertal growth spurt).DI stage H was associated with CVMI Ⅴ and Ⅵ(end of pubertal growth spurt).Conclusion:DI and CVMI are significantly associated.Mandibular second molar DI stage is a reliable indicator of skeletal maturity.

Comparison of landmark positions between Cone-Beam Computed Tomogram (CBCT) and Adjusted 2D lateral cephalogram / 대한치과보철학회지

PURPOSE: This study aims to investigate if 2D analysis method is applicable to analysis of CBCT by comparing measuring points of CBCT with those of Adjusted 2D Lateral Cephalogram (Adj-Ceph) with magnification adjusted to 100% and finding out at which landmarks the difference in position appear. MATERIALS AND METHODS: CBCT data and Adj-Ceph (100% magnification) data from 50 adult patients have been extracted as research objects, and the horizontal (Y axis) and vertical (Z axis) coordinates of landmarks were compared. Landmarks have been categorized into 4 groups by the position and whether they are bilaterally overlapped. Paired t-test was used to compare differences between Adj-Ceph and CBCT. RESULTS: Significant difference was found at 11 landmarks including Group B (S, Ar, Ba, PNS), Group C (Po, Or, Hinge axis, Go) and Group D (U1RP, U6CP, L6CP) in the horizontal (Y) axis while all the landmarks in vertical (Z) axis showed significant difference (P<.05). As a result of landmark difference analysis, a meaningful difference with more than 1 mm at 13 landmarks were indentifed in the horizontal axis. In the vertical axis, significant difference over 1 mm was detected from every landmark except Sella. CONCLUSION: Using the conventional lateral cephalometric measurements on CBCT is insufficient. A new 3D analysis or a modified 2D analysis adjusted on 19 landmarks of the vertical axis and 13 of the horizontal axis are needed when implementing CBCT diagnosis.

Long-term pharyngeal airway changes after bionator treatment in adolescents with skeletal Class II malocclusions / 대한치과교정학회지

OBJECTIVE: The aim of this study was to evaluate long-term changes in the pharyngeal airway dimensions after functional appliance treatment in adolescents with skeletal Class II malocclusions. METHODS: Pharyngeal airway dimensions were compared between subjects with skeletal Class II malocclusions (n = 24; mean age: 11.6 +/- 1.29 years) treated with a Class II bionator and age-matched control subjects with skeletal Class I occlusions (n = 24; mean age: 11.0 +/- 1.21 years) using a series of lateral cephalograms obtained at the initial visit (T0), after treatment (T1), and at the completion of growth (T2). RESULTS: The length of the nasopharyngeal region was similar between adolescents with skeletal Class I and Class II malocclusions at all time points, while the lengths of the upper and lower oropharyngeal regions and the pharyngeal airway areas were significantly smaller in the skeletal Class II adolescents before treatment when compared to the control adolescents (p < 0.05). However, following treatment with a functional appliance, the skeletal Class II adolescents had increased pharyngeal airway dimensions, which became similar to those of the control subjects. CONCLUSIONS: Functional appliance therapy can increase the pharyngeal airway dimensions in growing adolescents with skeletal Class II malocclusions, and this effect is maintained until the completion of growth.

Cervical vertebrae morphology in skeletal class Ⅱ and class Ⅰ malocclusion patients / 中国组织工程研究

BACKGROUND:The incidence rate of cervical abnormalities of the patients with skeletal class Ⅱ and normal occlusion has been studied abroad, but the researches on the incidence of cervical abnormalities in different malocclusion patients is rare at home. OBJECTIVE:To observe the imaging of patients with cervical abnormalities and to statistics the incidence of cervical abnormalities in different malocclusion patients through analyzing the lateral cephalogram of different malocclusion patients. METHODS:Skeletal class Ⅱ group was consisted of 93 patients, 41 male (aged 18-40 years) and 52 female (aged 22-35 years), with the A point-nasion-B point angle>5°. Class Ⅰ group was consisted of 45 patients, 31 female (aged 20-36 years) and 14 male (aged 17-38 years), with the 1°

Determination of the relative parallelism of occlusal plane to three ala-tragal lines in various skeletal malocclusions: A cephalometric study.

Background: Establishment of a proper occlusal plane is needed for developing an occlusion that is compatible with the biomechanics of a stomatognathic system. There has been a great deal of controversy regarding the anatomic reference point/s taken for identifying the Camper's plane (Ala-Tragus) to which the occlusal plane is oriented parallel in regular complete denture Prosthodontic practice. There has been no study in literature to correlate the occlusal plane to the Camper's plane in various skeletal malocclusions using landmarks on a lateral Cephalogram. Aim : The aim of the study isto determine the relative parallelism of the occlusal plane to ala- tragal lines in various malocclusions. Methodology: A total of sixty subjects belonging to Class I, Class II and class III malocclusions were selected for the study. Markings with radiopaque marker of 1 mm diameter were adhered against the superior, middle and inferior border of the tragus and against the lower borer of ala of the nose. Lateral cephalograms were obtained for all of the pateints. Tracing was performed for all of these radiographs. Statistical Analysis Used: Analysis of Variance (ANOVA) test and Post-Hoc test of Bonferroni were used to compare the angles formed at the superior, middle and inferior borders with the occlusal plane. Results: The result from the present study showed that in Class I and Class III malocclusion, the line drawn from the lower border of ala of the nose to the inferior position of the tragus (Camper' plane C) was relatively parallel to occlusal plane; and, in Class II malocclusion, the line drawn from the lower border of ala of nose to middle border of tragus (Camper's plane B) was relatively parallel to occlusal plane.

Accuracy and reproducibility of landmark of cone beam computed tomography (CT) synthesized cephalograms

INTRODUCTION: Cone beam computed tomography (CBCT) has various advantages and is used favorably in many fields in dentistry. Especially, CBCT is being used as basic diagnostic tool for 3-dimensional analysis in orthognathic patient. Two-dimensional cephalograms can be synthesized from CBCT digital imaging and communications in medicine (DICOM) data. In this study, conventional cephalograms and CBCT were taken simultaneously, and representative landmarks were located and analyzed in its accuracy and reproducibility. MATERIALS AND METHODS: Ten patients who had orthognathic surgery in Wonkwang University Daejeon Dental Hospital participated in this study. For each patient, CBCT and conventional cephalogram was taken. By using Ondemand (Cybermad, Korea), 2-dimensional cephalograms was established on CBCT. In addition, 19 landmarks were designated and measured by 3 orthodontists twice a week. After these landmarks were transferred to a coordinate, distance of landmark and axis, standard error, distribution degree were measured, compared and analyzed. RESULTS: Comparing the CT ceph group and conventional cephalogram group, CT ceph group had shown shorter distance of landmark and axis in S, Hinge axis, Bpt, Ba, Or, Corpus left. Standard error of the mean shows that CT ceph group has better reproducibility in Or, Corpus left, Hinge axis at X axis and Na, U1R, U1T, Bpt, PNS, Ba Corpus left, Hinge axis at Y axis. In both groups, mean error was less than 1.00 mm, no significant difference were found between CT ceph group and conventional cephalogram group in all measurements. Furthermore, comparing two groups, each 17 landmarks out of 19 had its characteristic in distribution degree. CONCLUSION: No significant difference were found between CBCT composed cephalographic radiograph and conventional cephalograghic radiograph, clinical application may be possible if improved.

Maturation of cervical vertebrae in relation to menarche / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to investigate the relationship between menarche and cervical vertebral maturation. METHODS: Lateral cephalograms of 67 young korean girls within the range of 1 year before or after their menarche were gathered. The concavity of the cervical vertebrae base and the ratio of the base length to the 3rd and 4th cervical vertebrae anterior height were measured and analyzed. RESULTS: The mean measured values were as follows; concavity of the 3rd cervical vertebrae base: 1.27 (+/- 0.18) mm, concavity of the 4th cervical vertebrae base: 1.06 (+/- 0.15) mm, ratio of the base length to the 3rd cervical vertebrae anterior height: 0.73 (+/- 0.06) and ratio of the base length to the 4th cervical vertebrae anterior height: 0.70 (+/- 0.05). There was a significant increase in the ratio of the base length to the 3rd vertebrae anterior height and the base concavity of the 3rd and 4th cervical vertebrae during the period of 1 year before to 1 year after their menarche. CONCLUSIONS: These characteristics of the 3rd and 4th cervical vertebrae on the lateral cephalogram can provide useful clues on evaluating the growth stage.

Cephalometric differences in obstructive sleep apnea between obese and non-obese Korean male patients / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to compare the cephalometric measurements of obese and non-obese Korean male patients with obstructive sleep apnea syndrome (OSA). METHODS: Eighty-seven adults who had visited the Sleep Disorder Clinic Center in Keimyung University, Daegu, Korea were examined and evaluated with polysomnography (PSG) and lateral cephalogram. They were divided into 4 groups (non-obese simple snorers, obese simple snorers, non-obese OSA patients, obese OSA patients) according to AHI (Apnea-Hypopnea Index) and BMI (Body Mass Index). RESULTS: The obese OSA group had the highest AHI among the 4 groups. The non-obese OSA group had a significantly steeper mandibular angle and shorter tongue length than the obese OSA group. The hyoid bone of the obese OSA group was positioned anterior and inferior as compared with the non-obese OSA group. Multiple regression analysis showed that tongue length in the obese OSA group and retroposition of hyoid bone in the non-obese OSA group were significant determinants for the severity of AHI. CONCLUSIONS: From a cephalometric point of view, the obese and non-obese pateints with OSA may be characterized by different pathogeneses. Therefore, they have to be managed by individualized treatment. For the obese OSA patients, weight control must be advised as a first choice and for the non-obese OSA patients, oral appliance, nasal CPAP, UPPP and others could be chosen according to the obstructive sites.