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INTRODUCTION: The use of arch models is essential in diagnosis and planning in orthodontics. The demand for digital and printed models has increased among professionals. OBJECTIVE: The aim of the study was to assess the agreement of horizontal and vertical linear measurements obtained from digital models, printed models, and direct measurements. MATERIALS AND METHODS: Intraoral scans of 30 individuals were obtained. Digital measurements were performed using the STL files. From printed models, the measurements were done using a digital caliper, and the real measurements were done directly to the mouth of respective patients. RESULTS: The one-sample t test showed no discrepancy between the paired sets of measurements, with the value of 0 (p>0.05). The evaluation of the measurements was done using Bland-Altman analysis in pairs. The three methods showed agreement in horizontal and vertical measurements. Linear regression analyses showed no proportional bias in the data (p>0.05). CONCLUSION: The horizontal and vertical measurements evaluated showed agreement when measured on digital models, printed models and directly in the individuals' mouths.

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INTRODUCTION: Symmetry is balance, some correspondence in the size, form, and arrangements of parts on opposite sides of a plane, line, or point. The opposite of this concept is asymmetry, or imbalance. OBJECTIVE: This retrospective study compared two methods for assessing arch symmetry with linear measurements based on triangles, to determine their applicability and efficiency. METHODS: Two groups were enrolled: children (n=20) and adults (n=20), and the arch symmetry was assessed from linear measurements. Method 1: the incisor-canine (INC), canine-molar (CM), and incisor-molar (INM) distances (paired t-test and Pearson correlation). Method 2: a mathematical equation between the cusps measurements of the canines and the distobuccal of the first molars leading to result 1 (t-test for one sample and bootstrapping analysis). Dental casts were digitized and analyzed using a software program. The Bland-Altman test compared the methods (α=0.05). RESULTS: The Bland-Altman test revealed concordance between the methods; however, separately the results were different: In method 1, the mandibular arch did not demonstrate correlation (children, INC r=0.33; CM r=0.45; INM r=0.51; adults, CM r=0.46; INM r=0.35), however, the maxilla revealed a strong correlation in children and a strong/moderate correlation in adults. In method 2, both arches were symmetrical (p>0.05). CONCLUSION: Method 1 may be appropriate during orthodontic treatment, and method 2 may be indicated for final treatment. These methods are useful; however, only method 1 identified the side of asymmetry. The methods can contribute to future studies in syndromic and non-syndromic patients, before and after orthognathic surgeries and orthodontic treatment, comparing results.

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INTRODUCTION: An ideal orthodontic treatment involves qualitative and quantitative measurements of dental and skeletal components to evaluate patients' discrepancies, such as facial, occlusal, and functional characteristics. Deciding between orthodontics and orthognathic surgery remains challenging, especially in borderline patients. Advances in technology are aiding clinical decisions in orthodontics. The increasing availability of data and the era of big data enable the use of artificial intelligence to guide clinicians' diagnoses. This study aims to test the capacity of different machine learning (ML) models to predict whether orthognathic surgery or orthodontics treatment is required, using soft and hard tissue cephalometric values. METHODS: A total of 920 lateral radiographs from patients previously treated with either conventional orthodontics or in combination with orthognathic surgery were used, comprising n = 558 Class II and n = 362 Class III patients, respectively. Thirty-two measures were obtained from each cephalogram at the initial appointment. The subjects were randomly divided into training (n = 552), validation (n = 183), and test (n = 185) datasets, both as an entire sample and divided into Class II and Class III sub-groups. The extracted data were evaluated using 10 machine learning models and by a four-expert panel consisting of orthodontists (n = 2) and surgeons (n = 2). RESULTS: The combined prediction of 10 models showed top-ranked performance in the testing dataset for accuracy, F1-score, and AUC (entire sample: 0.707, 0.706, 0.791; Class II: 0.759, 0.758, 0.824; Class III: 0.822, 0.807, 0.89). CONCLUSIONS: The proposed combined 10 ML approach model accurately predicted the need for orthognathic surgery, showing better performance in Class III patients.

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OBJECTIVE: This study compared mandibular growth in children, aged 7 to 12 years, with Class II malocclusion and normal occlusion, between the following stages of cervical vertebrae maturation: initiation (I), acceleration (A), transition (T). MATERIAL AND METHODS: A total of 148 lateral cephalograms (78 males, 70 females) of Class II malocclusion patients, and 60 lateral cephalograms (30 males, 30 females) of normal occlusion patients were included. The following linear cephalometric measurements were performed: Co-Gn (effective mandibular length), Co-Go (ramus height), and Go-Gn (length of mandibular body). Mean values of increments between stages (I-A, A-T, I-T) were obtained for each group and gender. Results were compared using the Student t-test, and a significance level of 0.05% was adopted. RESULTS: Females group: A-T interval presented a greater increment in Co-Go in the Class II group, which was not significant for the I-T interval, with numerically smaller increments in Co-Gn and Go-Gn, without statistical significance. Males group: intervals I-A, A-T and I-T showed numerically smaller growth increments in the Class II group, with statistical significance for Co-Gn in I-A (p=0.001) and I-T (p=0.003). Comparing genders of the Class II group, Co-Go was higher in males (p=0.002) and I-T interval (p=0.031). In the Normal Occlusion group, the male gender had the greatest Co-Gn (p=0.038) for the I-A interval. In A-T and I-T, Co-Go in males was higher, with statistical significance (p=0.000 and p=0.002, respectively). CONCLUSION: Growth phenomenon affects the mandibular dimensions regardless of the character of the malocclusion, with a tendency to be smaller in the presence of Class II malocclusion.

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OBJECTIVES: To evaluate the reliability and reproducibility of an artificial intelligence (AI) software in identifying cephalometric points on lateral cephalometric radiographs considering four settings of brightness and contrast. METHODS AND MATERIALS: Brightness and contrast of 30 lateral cephalometric radiographs were adjusted into four different settings. Then, the control examiner (ECont), the calibrated examiner (ECal), and the CEFBOT AI software (AIs) each marked 19 cephalometric points on all radiographs. Reliability was assessed with a second analysis of the radiographs 15 days after the first one. Statistical significance was set at p < 0.05. RESULTS: Reliability of landmark identification was excellent for the human examiners and the AIs regardless of the type of brightness and contrast setting (mean intraclass correlation coefficient >0.89). When ECont and ECal were compared for reproducibility, there were more cephalometric points with significant differences on the x-axis of the image with the highest contrast and the lowest brightness, namely N(p = 0.033), S(p = 0.030), Po(p < 0.001), and Pog'(p = 0.012). Between ECont and AIs, there were more cephalometric points with significant differences on the image with the highest contrast and the lowest brightness, namely N(p = 0.034), Or(p = 0.048), Po(p < 0.001), A(p = 0.042), Pog'(p = 0.004), Ll(p = 0.005), Ul(p < 0.001), and Sn(p = 0.001). CONCLUSIONS: While the reliability of the AIs for cephalometric landmark identification was rated as excellent, low brightness and high contrast seemed to affect its reproducibility. The experienced human examiner, on the other hand, did not show such faulty reproducibility; therefore, the AIs used in this study is an excellent auxiliary tool for cephalometric analysis, but still depends on human supervision to be clinically reliable.

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INTRODUCTION: This study aimed to evaluate if there were differences between anterior and posterior anatomic boundaries used for the 3-dimensional determination of pharyngeal airway. METHODS: The sample included 150 cone-beam computed tomography scans from healthy patients divided according to (1) age: 6-11, 12-16, and ≥16 years; (2) sex: female and male; (3) anteroposterior skeletal pattern: Class I, II, and III; (4) vertical pattern: brachyfacial, mesofacial, and dolichofacial; and (5) craniocervical inclination (CCI): natural head posture, head flexion, and head extension. Anatomic regions were created to determine the correspondences between structures anteriorly and posteriorly to the pharyngeal airway. RESULTS: The location of the epiglottis, vallecula, hyoid, C2, and C3 were statistically different according to the CCI, and the location of vallecula, C3, and C4 were different according to sex. However, no statistically significant differences were observed between the frequencies of anterior and posterior anatomic region locations among age and different anteroposterior and vertical skeletal patterns. Posterior landmarks tend to be located below the anterior ones; consequently, the anatomic subregion they define will also be located below. CONCLUSIONS: Anterior and posterior structures and vertical and anteroposterior skeletal patterns may determine upper airway limits regardless of age. However, the studies must be paired according to sex, and CCI must be standardized.

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Paciente de 21 años de sexo masculino con una distoclusión esqueletal y alveolo dentaria severa, hábito de succión del dedo que contribuye a agravar el escalón de 15 mm. Demanda tratamiento para mejorar su oclusión y estética. Si bien lo indicado es un tratamiento ortodóncico con cirugía ortogná- tica para modificar su perfil muy convexo con una distancia mentocervical acortada, no es aceptado por el paciente, planificándose entonces camuflaje ortodóncico con exodoncias de PD 14 y 24 y reduc- ción del escalón mediante anclaje diferencial que emplea fuerzas de volcamiento para no perderlo dado el gran overjet a reducir. Habiendo varias piezas dentarias con anomalías de color, defectos en el esmalte, una corona metálica en PD 36 y limitacio- nes presupuestarias se realizó la estética final con reconstrucciones de resina (AU)

A 21-year-old male patient with a severe skeletal and alveolar distoclusion, finger sucking habit that contributes to aggravate the 15 mm step. He demands treatment to improve its occlusion and aesthetics. Although orthodontic treatment with orthognathic surgery is indicated to modify its highly convex profile with a shortened mentocervical distance, it is not accepted by the patient, so orthodontic camouflage is planned with extractions of 14 and 24 and reduction of the step by means of differential anchorage that uses overturning forces so as not to lose anchorage due to the great overjet. Having several dental pieces with color anomalies, enamel defects, a metallic crown in 36 and budgetary limitations, the final aesthetics was performed with resin reconstructions (AU)

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BACKGROUND: Since the muscles of chewing are involved in the region of the mandibular angle, important structures in surgical and orthodontic procedures, to study its morphological aspects and the possible influence of different patterns of skeletal development would be of interest. Thus, this study aimed to assess the influence of patient characteristics - such as sex, skeletal malocclusion (Class I, Class II, and Class III) and facial type (brachycephalic, mesocephalic, and dolichocephalic) - on the width, height, thickness, and volume of the mandibular angle, using cone-beam computed tomography (CBCT) scans. METHODS: CBCT scans were assessed - 144 men and 154 women, total of 298 - and classified according to skeletal patterns (skeletal malocclusions and facial types). Width, height, and thickness of the mandibular angle were measured using OnDemand 3D software. The volumetric measures of the mandibular angle were obtained using the ITK-SNAP software. Analysis of Variance (multiway ANOVA) with Tukey's post-hoc test compared the data, with a 5% significance level. RESULTS: Among the factors studied, sex significantly influenced all the analyzed variables (height, width, thickness, and volume of the mandibular angle) (p < 0.05); in general, male individuals presented higher values than females. In some cases, the skeletal malocclusion and facial type factors influenced only the width and height variables (p < 0.05); in general, the Class III and dolichocephalic individuals presented higher values in relation to the other types of skeletal malocclusions and facial types. CONCLUSIONS: Variations in the craniofacial growth pattern, considering the different skeletal malocclusions and facial types, had some influence in the width and height dimensions of the mandibular angle. Furthermore, sex influenced all the studied variables.

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INTRODUCTION: The aim of this cross-sectional study was to investigate maxillomandibular morphology in hyperdivergent and hypodivergent individuals, using 3D surface models generated by cone-beam computed tomography (CBCT). METHODS: The sample consisted of 60 CBCTs (30 males, 30 females) patients aged 12-30 years, divided into two groups comprising hyperdivergent (≥35°) and hypodivergent (≤30°) individuals, according to the mandibular plane (MP) angle. Multiplanar reconstructions were used to mark the landmarks, and 3D surface models were created to evaluate structures of the maxillomandibular complex, including condyle, ramus, symphysis and palatal height. Intergroup comparisons were performed by independent t-test. Pearson's correlation test was used (P < .05) to evaluate the correlation of the MP angle with the angles and linear measurements of other structures. RESULTS: Significant differences were found between the groups regarding condylar width, ramus height, condylar plus ramus height, mandibular length, gonial angle, palatal plane angle and palatal-mandibular angle. No differences (P > .05) were found for the condylar height, symphysis inclination angle or palatal height. Correlations (P < .05) were found between the MP angle and structures of the maxillomandibular complex. CONCLUSIONS: Hyperdivergent (MP ≥ 35°) and hypodivergent (MP ≤ 30°) individuals present different skeletal morphology regarding condylar width, ramus height, condylar plus ramus height, mandibular length, gonial angle, palatal plane angle and palatal-mandibular angle. There is a significant correlation between MP angle and morphological structures such as condyle, ramus, symphysis, palatal plane angle and palatal-mandibular angle.

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INTRODUCTION: A systematic review of the literature available up to October 2020 has been conducted to determine which cranial plane could represent a stable and reliable parameter to evaluate the orientation of the occlusal plane in a frontal view. EVIDENCE ACQUISITION: An electronic research was performed across the following electronic databases: PUBMED, EBSCO, SCOPUS, WoS, COCHRANE LIBRARY, SciELO, EMBASE and GOOGLE SCHOLAR. Observational studies based on imaging and anthropometry were identified, and all languages have been included. The articles were selected and analyzed by three authors independently. PICO format was adopted to analyze the studies and AXIS guidelines were used to assess the quality of evidence. EVIDENCE SYNTHESIS: We found eleven articles eligible for full-text analysis. All studies included only young subjects and analyzed the occlusal plane in relation to the frontal plane traced between the right and left tragus (Camper's and Frankfurt planes), to the interpupillary plane, and to other soft and hard tissues references. The outcomes of selected studies were various, with a low quality of evidence, and they did not allow to infer a stable cranial relation between the occlusal plane and other bone structures. CONCLUSIONS: The evidence does not support that the interpupillary plane represent a reliable parameter to evaluate the occlusal plane orientation in a frontal view; instead, the Frankfurt plane could be a much more stable reference parameter, from a morphological perspective. It is necessary to perform an observational study upon craniums to define which are the most stable cranial reference planes to determine the orientation of the occlusal plane in dentate subjects.

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INTRODUCTION: It has been suggested that human errors during manual tracing of linear/angular cephalometric parameters can be eliminated by using computer-aided analysis. The landmarks, however, are located manually and the computer system completes the analysis. With the advent of Artificial Intelligence in the field of Dentistry, automatic location of the landmarks has become a promising tool in digital Orthodontics. METHODS: Fifty pretreatment lateral cephalograms obtained from the Orthodontic department of SRM dental college (India) were used. Analysis were done by the same investigator using the following methods: WebCeph™, AutoCEPH© for Windows or manual tracing. Landmark identification was carried out automatically by Artificial Intelligence in WebCeph™ and with a mouse driven cursor in AutoCEPH©, and manually using acetate sheet and 0.3-mm pencil, ruler and a protractor. The mean differences of the cephalometric parameters obtained between the three methods were calculated using ANOVA with statistical significance set at p<0.05. Intraclass correlation coefficient (ICC) was used to determine both reproducibility and agreement between linear and angular measurements obtained from the three methods and intrarater reliability of repeated measurements. ICC value of >0.75 indicated good agreement. RESULTS: Intraclass correlation coefficient between the three groups was >0.830, showing good level of agreement, and the value within each group was >0.950, indicating high intrarater reliability. CONCLUSION: Artificial Intelligence assisted software showed good agreement with AutoCEPH© and manual tracing for all the cephalometric measurements.

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INTRODUCTION: This study evaluated mandibular morphology and transverse dental compensation between symmetrical and asymmetrical subjects, allocated according to sagittal skeletal patterns. In addition, the hypothesis that mandibular morphology and dental compensations differed between symmetrical/asymmetrical groups and also among the different types of sagittal skeletal patterns was tested. METHODS: Cone-beam computed tomography images of 96 patients were included in this study and were divided into 2 groups according to the degree of menton deviation: a symmetrical group with deviation up to 2.0 mm (n = 48; mean age, 15 ± 6 years), and an asymmetrical group with deviation from 3.5 mm (n = 48; mean age, 16 ± 8 years). The 2 groups were divided in accordance with the ANB angle: Class I, II, and III. Skeletal and dental measurements were performed. Intergroup and intragroup analyses were carried out, using a 2-way analysis of variance to assess the interaction of factors: symmetry and sagittal skeletal pattern; and the Student t test for differences between deviated (Dv) and nondeviated (NDv) sides. RESULTS: Symmetrical/asymmetrical groups and Class I, II, and III groups were similar in relation to demographic aspects (P = 0.412 and P = 0.357 for sex and age, respectively). Asymmetrical patients had higher values for body length and mandibular ramus and condyle height on the NDv side (P = 0.011, P = 0.024, and P = 0.001, respectively). When comparing the different skeletal patterns, patients with a Class III relationship demonstrated higher values for mandibular ramus height. Intergroup analysis showed no differences in dental parameters. In the comparison between the sides, the asymmetrical group showed a significant difference in canine inclination (P = 0.008), mandibular ramus height (P = 0.004), condyle height (P = 0.010) and gonion to midsagittal plane distance (P = 0.018). CONCLUSIONS: Asymmetrical subjects showed higher values for canine inclination and mandibular body, ramus and condylar height on the NDv side. The hypothesis was partially confirmed that mandibular morphology and dental compensations are different between symmetrical/asymmetrical groups and among different sagittal skeletal patterns.

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The aim of this retrospective cross-sectional investigation was to perform a 3D analysis of craniofacial morphology of patients with unilateral cleft lip and palate (UCLP) at two stages of skeletal maturation. Cone-beam computed tomography (CBCT) scans of 52 UCLP patients (34 prepubertal; 18 pubertal) were collected from an outpatient referral center for the treatment of craniofacial deformities. In total 15 multiplanar craniofacial landmarks were identified, 3D virtual surface models were created, and 13 variables were measured to assess the 3D Euclidean distances between landmarks and spatial position of the landmarks in the projected X, Y and Z components. Maxillary and mandibular pitch (clockwise, counterclockwise) rotation relative to the cranial base was also evaluated. The significance level was set at 5%. Maxillary retrusion value relative to the cranial base was higher and statistically significant greater (p = 0.028) in pubertal (SNA, 77.4° ± 6.2; N-ANS Y, 3.3 mm ± 3.1) than in prepubertal patients (SNA 81.0° ± 5.2; N-ANS Y, 5.8 mm ± 2.7). The posterior cranial base length (S-Ba Y) was significantly longer (p = 0.013) in pubertal (20.7 mm ± 3.4) than in prepubertal patients (18.4 mm ± 2.7). The upper facial height (N-ANS Z) was significantly greater (p = 0.01) in pubertal (46.9 mm ± 4.5) than in prepubertal patients (43.4 mm ± 3.0). Prepubertal and pubertal UCLP patients presented distinct patterns of craniofacial morphology, mainly in the sagittal component of the maxilla and in the posterior cranial base length. Pubertal patients had greater maxillary retrusion and posterior cranial base length.

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OBJECTIVE: We report the orthodontic treatment of a class II malocclusion with anterior open bite and posterior crossbite in a patient with Down syndrome (DS) treated with mini-implants. METHODS: Treatment began with rapid maxillary expansion with a Haas appliance, followed by dental alignment and leveling with a fixed appliance and the correction of class II dental relationships with the use of orthodontic mini-implants associated with a sliding jig. RESULTS: The results obtained at the end of the treatment were satisfactory, with improvements in occlusion, including bite closure; maxillary expansion; and the correction of dental relationships. CONCLUSION: When well-planned, orthodontic treatment in a patient with DS achieves satisfactory results from a skeletal, occlusal, and facial perspective.

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Using computer vision through artificial intelligence (AI) is one of the main technological advances in dentistry. However, the existing literature on the practical application of AI for detecting cephalometric landmarks of orthodontic interest in digital images is heterogeneous, and there is no consensus regarding accuracy and precision. Thus, this review evaluated the use of artificial intelligence for detecting cephalometric landmarks in digital imaging examinations and compared it to manual annotation of landmarks. An electronic search was performed in nine databases to find studies that analyzed the detection of cephalometric landmarks in digital imaging examinations with AI and manual landmarking. Two reviewers selected the studies, extracted the data, and assessed the risk of bias using QUADAS-2. Random-effects meta-analyses determined the agreement and precision of AI compared to manual detection at a 95% confidence interval. The electronic search located 7410 studies, of which 40 were included. Only three studies presented a low risk of bias for all domains evaluated. The meta-analysis showed AI agreement rates of 79% (95% CI: 76-82%, I2 = 99%) and 90% (95% CI: 87-92%, I2 = 99%) for the thresholds of 2 and 3 mm, respectively, with a mean divergence of 2.05 (95% CI: 1.41-2.69, I2 = 10%) compared to manual landmarking. The menton cephalometric landmark showed the lowest divergence between both methods (SMD, 1.17; 95% CI, 0.82; 1.53; I2 = 0%). Based on very low certainty of evidence, the application of AI was promising for automatically detecting cephalometric landmarks, but further studies should focus on testing its strength and validity in different samples.

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BACKGROUND: Head circumference (HC) correlates with brain growth and development. However, radiologists typically use their visual impressions to evaluate head dimensions, which is a purely subjective assessment. OBJECTIVE: The first objective of this paper was to analyze whether it is possible to obtain HC measurements by CT and MRI cross-sectional volumetric imaging using parameters similar to the tape measurement method, which is considered the gold standard. The second objective was to determine the most accurate method for characterizing head size: visual impression or imaging measurement. MATERIALS AND METHODS: Children who underwent HC measurement by tape and with volumetric imaging exams were selected from the Paulo Niemeyer State Brain Institute, Brazil. Two radiologists classified the children's heads using their visual impressions and by direct measurement on imaging. We used anatomical parameters similar to the tape measurement method and appropriate head growth charts and compared the absolute values obtained. RESULTS: The concordance between tape and imaging ranged 52.3-72.7% for visual impression (kappa 0.27-0.55), ≥ 95.5% for CT and ≥ 93.1% for MRI (kappa ≥ 0.92 and ≥ 0.88, respectively). Intraclass correlation coefficients ≥ 0.997 and ≥ 0.996, absolute technical error measurements of 0.20-0.31 cm and 0.24-0.29 cm, and relative technical error measurements of 0.49-0.73% and 0.58-0.70% were evidenced in the intra- and inter-rater evaluations, respectively. The means between the methods were not significantly different (P > 0.05), with high values of Pearson correlation coefficient (≥ 0.99) and Lin concordance correlation coefficient (≥ 0.99). CONCLUSION: Head circumference values obtained by cross-sectional volumetric imaging are similar to those obtained using the tape measurement method (gold standard), with high repeatability and reproducibility. Head size characterization by visual impression is less accurate than head circumference measurement by imaging and plotting the values obtained on World Health Organization normative charts.

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OBJECTIVE: To assess volume and surface of the mandibular condyle on cone beam computed tomography (CBCT) scans by comparing Class I, II, and III malocclusions. METHODS: CBCT scans of 55 patients were assessed to measure ANB angle, condyle volume, and surface by using VistaDent software. The values were compared between the different skeletal malocclusions and correlated to gender and sides. Kruskal-Wallis test was used for comparison of malocclusions and Mann-Whitney test and Wilcoxon test for comparisons of genders and sides. Statistical significance was defined as p < 0.05. RESULTS: There were no significant differences in volume (p = 0.588) and surface (p = 0.830) between the malocclusion classes. The comparison between sides showed a statistically significant difference for surface (p = 0.038). CONCLUSION: Condylar volume and surface evaluated on CBCT scans showed no statistically different values for Class I, II, and III malocclusions.

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PURPOSE: The aim of the study was to investigate a possible relationship between pharyngeal airway space, craniofacial variables, and dental arch form in adolescents grouped by sex. METHODS: This cross-sectional study included 108 adolescents aged between 12 and 17 years. Lateral cephalometric radiographs were used to analyze sagittal craniofacial variables and the pharyngeal airway space. For evaluation of the dental arch form, we used plaster models. Statistical analysis included Student's t­test and Pearson's correlation coefficient (r). RESULTS: Maxillary length was directly proportional to upper nasopharyngeal airway dimensions in males (r = 0.312, p = 0.021) and females (r = 0.310, p = 0.022). In the female group, upper oropharyngeal measurements showed an inverse correlation with a labial inclination of the upper incisors (r = -0.415, p = 0.001), protrusion of the upper incisors (r = -0.364, p = 0.006), and soft palate thickness (r = -0.27, p = 0.043). In the male group, upper nasopharynx measurements showed an inverse correlation with soft palate thickness (r = -0.277, p = 0.042). The upper arch form appeared to be related to oropharyngeal measurements in females, while the lower arch form was related to oropharyngeal dimensions in males. CONCLUSION: The findings suggest that there are sex-dependent correlations of the nasopharyngeal and oropharyngeal airway space with the sagittal craniofacial morphology and the transversal dental arch form.

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PURPOSE: This study aimed to analyze alterations in mandibular positioning after surgically assisted maxillary expansion (SARME) with and without pterygoid disjunction (PD). METHODS: Cone-beam computed tomography scans of 24 healthy individuals (18-45 years old) with transverse deficiency, superior to 5 mm, underwent SARME with or without PD. The aspects prospectively assessed were (1) alignment and position of the head (ITK-Snap and 3D Slicer software); (2) McNamara's and Steiner-Tweed-Wits' cephalometric analysis (Dolphin Imaging®); and (3) colorimetric evaluation based on 3D correspondence analysis (3D Slicer software). RESULTS: A decrease in 1-NA and 1-SN angles as well as an increased occlusal plane in both groups was observed. Superior-inferior and anteroposterior spatial displacements of the chin were statistically significant in the PD group. Altered colorimetric patterns were also observed in the PD group. CONCLUSIONS: This study found more evident tooth inclination in the group without PD; mandibular alterations were more evident in the PD group. Further studies with 3D analysis are strongly recommended for more comprehensive results.

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BACKGROUND/OBJECTIVES: Intraoral distalizers are effective and conservative alternatives for Class II malocclusion treatment. However, the literature is still controversial regarding the effects of using skeletal anchorage in intraoral distalizers with different designs. The aim of this study is to compare dentoskeletal and soft-tissue changes of Class II malocclusion patients treated with three types of First Class (FC) distalizers. MATERIALS/METHODS: The sample of this prospective clinical trial included 30 consecutive patients divided into three groups: G1-FC conventionally anchored; G2-FC skeletally anchored Type 1; G3-FC skeletally anchored Type 2. Each group consisted of 10 patients. Lateral cephalograms were analyzed in two stages: at pre-treatment (T0) and after distalization (T1). The radiographs were digitized and analyzed using the software Dolphin Imaging 11.5. Comparisons of treatment changes between groups (T1-T0) were performed using one-way analysis of variance (ANOVA), followed by the Tukey test. RESULTS: Patients treated with the conventionally anchored FC showed significantly greater incisors protrusion and labial inclination, second premolars mesial inclination and mesialization than the FCs skeletally anchored. No differences were observed regarding the amount of molar distalization and molar angulation between groups. LIMITATIONS: It can be considered that the limitation of this study lies in its non-randomized design. CONCLUSIONS/IMPLICATIONS: First Class distalizers with conventional and skeletal anchorage are effective alternatives for Class II molar distalization. Distalization associated with indirect skeletal anchorage reduce the undesirable effects observed in the incisors and premolars during distalization when compared to distalization conventionally anchored.

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