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Background: The World Health Organization considers malocclusion one of the most essential oral health problems. This disease influences various aspects of patients' health and well-being. Therefore, making it easier and more accurate to understand and diagnose patients with skeletal malocclusions is necessary., Objectives: The main aim of this research was the establishment of machine learning models to correctly classify individual Arab patients, being citizens of Israel, as skeletal class II or III. Secondary outcomes of the study included comparing cephalometric parameters between patients with skeletal class II and III and between age and gender-specific subgroups, an analysis of the correlation of various cephalometric variables, and principal component analysis in skeletal class diagnosis., Methods: This quantitative, observational study is based on data from the Orthodontic Center, Jatt, Israel. The experimental data consisted of the coded records of 502 Arab patients diagnosed as Class II or III according to the Calculated_ANB. This parameter was defined as the difference between the measured ANB angle and the individualized ANB of Panagiotidis and Witt. In this observational study, we focused on the primary aim, i.e., the establishment of machine learning models for the correct classification of skeletal class II and III in a group of Arab orthodontic patients. For this purpose, various ML models and input data was tested after identifying the most relevant parameters by conducting a principal component analysis. As secondary outcomes this study compared the cephalometric parameters and analyzed their correlations between skeletal class II and III as well as between gender and age specific subgroups., Results: Comparison of the two groups demonstrated significant differences between skeletal class II and class III patients. This was shown for the parameters NL-NSL angle, PFH/AFH ratio, SNA angle, SNB angle, SN-Ba angle. SN-Pg angle, and ML-NSL angle in skeletal class III patients, and for S-N (mm) in skeletal class II patients. In skeletal class II and skeletal class III patients, the results showed that the Calculated_ANB correlated well with many other cephalometric parameters. With the help of the Principal Component Analysis (PCA), it was possible to explain about 71% of the variation between the first two PCs. Finally, applying the stepwise forward Machine Learning models, it could be demonstrated that the model works only with the parameters Wits appraisal and SNB angle was able to predict the allocation of patients to either skeletal class II or III with an accuracy of 0.95, compared to a value of 0.99 when all parameters were used ("general model")., Conclusion: There is a significant relationship between many cephalometric parameters within the different groups of gender and age. This study highlights the high accuracy and power of Wits appraisal and the SNB angle in evaluating the classification of orthodontic malocclusion., (© 2024. The Author(s).)

Background: Many indices have been suggested to help orthodontists in predicting the ideal dental arch width. One of these was Pont's index which was established by Pont. He suggested equations to predict the ideal maxillary dental arch width (interpremolar and intermolar) from the combined mesiodistal width of the maxillary incisors. This study aimed to test the applicability of Pont's index as an orthodontic diagnostic tool in Egyptian population and to compare the results with those obtained from studies of different ethnic subjects., Methods: This study was performed using dental casts of 184 Egyptian individuals (82 males and 102 females; age range, 19-24 years). The casts were divided into 46 casts with normal occlusion, 46 casts with class I, 46 casts with class II and 46 casts with class III malocclusion, according to Angle's classification. Alginate impressions were taken for all patients and poured immediately using dental plaster. The real models were transformed into digital models using three-dimensional laser scanner to allow digital model analysis. Predicted arch widths were calculated using Pont's equations. The predicted values were compared to the measured values., Results: Intra class correlation coefficient (ICC) (absolute agreement) between measured and predicted arch widths was determined. Poor absolute agreement was found between measured arch width values and the corresponding values calculated according to Pont's index., Conclusion: According to the results of this study, Pont's index is not a reliable method for predicting the ideal dental arch widths in Egyptian populations., (© 2024. The Author(s).)

Introduction: This study aimed to determine a measurement plane that could represent the maximum cross-sectional area (MCSA) of masseter muscle using an artificial intelligence model for patients with skeletal Class III malocclusion., Methods: The study included 197 patients, divided into subgroups according to sex, mandibular symmetry, and mandibular plane angle. The volume, MCSA, and the cross-sectional area (CSA) at different levels were calculated automatically. The vertical distance between MCSA and mandibular foramen, along with the ratio of the masseter CSA at different levels to the MCSA (R), were also calculated., Results: The MCSA and volume showed a strong correlation in the total sample and each subgroup (P <0.001). The correlation between the CSA at each level and MCSA was statistically significant (P <0.001). The peak of the r and the correlation coefficient between the CSA at different levels and MCSA were mostly present 5-10 mm above the mandibular foramen for the total sample and the subgroups. The mean of R A5 to R A10 was >0.93, whereas the corresponding correlation coefficient was >0.96, both for the entire sample and for the subgroups., Conclusions: MCSA could be used as an indicator for masseter muscle size. For patients with skeletal Class III malocclusion, the CSA 5-10 mm above the mandibular foramen, parallel to the Frankfort plane, could be used to estimate the masseter muscle MCSA., (Copyright © 2024 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

To compare craniofacial and cervical morphology between skeletal Classes II and III applying Geometric Morphometric Methods (GMM). Twenty-six cervical and craniofacial landmarks of 40 Class II and 39 Class III individuals were digitalized on lateral cephalograms. Procrustes ANOVA, generalized Procrustes, principal component analyses, and thin-plate spline function were applied to assess the pattern of shape variation of craniofacial structure and the cervical spine in relation to skeletal classes. Compared with Class III, Class II individuals presented a maxillary protrusion, mandibular retrusion, shorter mandibular corpus, posterior mandibular ramus rotation, anterior cranial base rotation, and a smaller centroid size. Furthermore, a forward and smaller cervical spine were observed. With GMM, the shape and size differences between skeletal classes can be analyzed visually and numerically.

Background: This study aims to verify Bolton's values for tooth size ratios and to evaluate possible relationships to different occlusal traits using precise digital measurement methods., Materials and Methods: Including 1000 consecutively selected patients from three study centres a digital, partially automated model analysis was performed utilizing the software OnyxCeph. The measurements comprised tooth width for calculation of anterior (AR) and overall ratio (OR) as a percentage, arch width, length, perimeter, overjet, overbite, space analysis in millimetre and the assessment of the angle classification., Results: AR and OR were significantly increased compared to Bolton's ratios of 77.2% (AR) and 91.3% (OR). In the gender comparison, male patients showed larger tooth size ratios, especially in the OR. Patients with Angle Class II/1 and II/2 had smaller tooth size ratios than patients with Angle Class III and I. Thus, patients with Angle Class II/1 had the largest tooth diameters in all maxillary teeth and with Angle Class II/2 the smallest tooth sizes in the mandible. The largest tooth widths in the lower jaw were observed in the Angle Class III patient group. Furthermore, a negative correlation from AR/OR to overjet, overbite, and available space in lower jaw as well as a positive correlation to available space in upper jaw was detected., Conclusions: There is a clear correlation between the tooth size ratios and the present dysgnathia as well as other orthodontically relevant occlusal traits. This prior knowledge about our patients is extremely important to create an individualized treatment plan and enable sufficient occlusion. To achieve a functionally good occlusion with correct overjet and overbite, it is essential that the maxillary and mandibular teeth are proportional in size. Any deviation from the ideal patient in terms of tooth size, number, shape, or arch must be considered in the pre-therapeutic treatment plan in combination with the existing dysgnathia in order to be able to achieve a stable anterior and posterior occlusion with appropriate adjustments to the therapy post-therapeutically., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: The aim of the study was to assess the thickness of the soft tissue facial profile (STFP) in relation to the skeletal malocclusion, age and gender., Methods: All patients, aged 7-35 years, who were seeking orthodontic treatment at the Department of Orthodontics, Medical University of Warsaw between 2019 and 22 were included in the study. All patients had lateral head radiographs taken before the treatment. The cephalometric analysis was performed including the STFP analysis. The patients were allocated to one of six groups based on age and skeletal relations (ANB angle). The minimum number of patients in each group was 60 with equal gender distribution. The STFP analysis included ten linear measurements., Results: A total of 300 patients were included in the study and allocated to five groups. Group 6 (growing patients with skeletal Class III malocclusion) was not included in the study as it failed to achieve the assumed group size. There were significant differences in the thickness of the STFP in relation to the skeletal malocclusions. Adults with skeletal Class III malocclusion had significantly thicker subnasal soft tissues compared to patients with skeletal Class I and Class II malocclusions. The thickness of the lower lip in patients with Class II skeletal malocclusion was significantly bigger compared to the other groups. Children and adolescents with Class II malocclusions had thicker lower lip in comparison to the group with Class I malocclusion. The majority of the STFP measurements were significantly smaller in children and adolescents compared to adults. The thickness of the STFP in males was significantly bigger in all age groups compared to females., Conclusions: The thickness of facial soft tissues depends on the patient's age and gender. The degree of compensation of the skeletal malocclusion in the STFP may be a decisive factor during orthodontic treatment planning regarding a surgical approach or a camouflage treatment of skeletal defects., (© 2024. The Author(s).)

Objectives: To investigate the internal structure of the nasomaxillary complex, including the maxillary sinus, nasal cavity and nasal septum according to the facial asymmetry pattern and to evaluate its correlation with external maxillomandibular asymmetry in Class III patients based on cone-beam computerized tomography (CBCT) images., Materials and Methods: Facial asymmetry was analysed in a total of 100 Class III patients aged 16 years or older using CBCT scans. Patients were categorized into subgroups based on asymmetry pattern. Measurements of the nasomaxillary complex were obtained from the CBCT scans, including the volume and width of the maxillary sinuses and nasal cavities on deviated and non-deviated sides, as well as the displacement of the nasal septum. Statistical analysis was performed to compare the internal nasomaxillary variables within and between groups, and regression analysis was conducted to evaluate the correlation between facial asymmetry and the internal nasomaxillary variables., Results: Group comparisons showed that there were no significant differences in the volume of the maxillary sinus and nasal cavity. However, the direction and extent of nasal septum deviation, as well as the width of the nasal cavity, varied depending on the maxillary asymmetry pattern. Regression analysis indicated a correlation between nasal septum deviation and the difference in maxillary height, while the difference in nasal cavity width was correlated with the difference in maxillary width., Conclusion: A comprehensive evaluation of the internal nasal anatomy is vital for understanding the intricate relationship between nasal structure and maxillary growth., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: The objective of the study was to elucidate the association between cranial base (Bjork-Jarabak analysis), midsagittal cross-sectional area of the airway in the pharyngeal region (MCSA-PR) data and pharyngeal-airway volume (PAV) and develop a model that could help clinicians predict PAV using two-dimensional (2D) data (Bjork polygon and MCSA-PR)., Materials and Methods: Pre-treatment lateral cephalometric radiographs and magnetic resonance imaging (MRI) scans of 82 women were categorized into three anteroposterior skeletal groups based on ANB angle: Class I (n = 29), 1.5° ≤ ANB≤5.1°; Class II (n = 26), ANB >5.1°; Class III (n = 27), ANB <1.5°. The Bjork polygon, MCSA-PR data from cephalograms and PAV data from MRI scans were examined. Intergroup comparisons were performed using the Kruskal-Wallis test and one-way analysis of variance (ANOVA), with pairwise comparisons conducted using the Bonferroni-corrected Mann-Whitney U-test for the Kruskal-Wallis test and Bonferroni-corrected multiple comparison test for one-way ANOVA. Forward multiple linear regression was used to create model equations for predicting PAV., Results: MCSA-PR and anterior (N-S) and posterior (S-Ar) cranial-base lengths were positively correlated with the PAV. We developed four models; three operated at the group level, and one encompassed the entire sample. Notably, all models could effectively explain the variance in the PAV data. The model for the Class I group was the strongest (adjusted R 2  = 0.77)., Conclusion: Our findings indicate the remarkable potential of the MCSA-PR, N-S and Bjork sum angles (BSA) as predictors of the PAV and the relevance of 2D cephalometric and cranial-base parameters in predicting the three-dimensional (3D) pharyngeal-airway size., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: This study aimed to evaluate the position of the mandibular lingula (ML) in adult patients (aged between 18 and 35 years old) with different skeletal and growth patterns using cone-beam computed tomography (CBCT)., Design: Cross-sectional., Setting: Dentistry department of University., Subjects: Subjects comprised CBCT images of 150 adult patients, including 300 rami., Methods and Materials: In total, 150 CBCT aged between 18 and 35 were selected and divided into three main groups of 50 samples based on their skeletal relationships (classes I, II and III). Patients were subdivided based on their growth pattern (vertical vs. horizontal), resulting in 25 samples per subgroup. Distances between the mandibular lingula and occlusal plane (ML-OP), sigmoid notch (ML-SN), external oblique ridge (ML-EOR), internal oblique ridge (ML-IOR), posterior border of the ramus (ML-PBR), inferior border of the ramus (ML-IBR), and horizontal and vertical distances to the mandibular foramen (ML-hMF and ML-vMF). One-way ANOVA variance analysis was employed to compare different angle classifications, and Bonferroni analysis was used for multiple comparisons. The Student's t-test was also used to compare growth patterns within each main group and genders within the subgroup., Results: The study revealed statistically significant differences in the position of the mandibular lingula between different angle classifications, growth patterns, and genders. Class II samples showed a more anterior position of the ML, whereas Class III samples displayed a more posterior position of the ML. Patients with horizontal growth patterns and Angle Class III had a more posteriorly positioned ML. Gender differences were observed, particularly in Class I and Class III classifications, suggesting that gender may influence the variability of ML position in these specific classifications., Conclusion: The position of the mandibular lingula showed high variability among individuals with different angle classifications, growth patterns and genders., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To assess the skeletal and dental maxillary transverse compensation (yaw) on the cone beam computed tomography (CBCT) three-dimensional reconstructed image of the skull in two groups of patients, both clinically affected by a class III malocclusion with deviation of the lower midline., Materials and Methods: An observational retrospective study was designed to analyse differences in two groups of patients, the first one was composed by patients affected by horizontal condylar hyperplasia, the second one by patients affected by dento-skeletal asymmetric class III malocclusion. Each group was composed by 15 patients. Transverse analysis was performed by measuring five landmarks (three bilateral and two uneven) with respect to a mid-sagittal plane; sagittal analysis was performed by measuring the sagittal distance on the mid-sagittal plane between bilateral points. Means were compared through inferential analysis., Results: In the condylar hyperplasia group, all differences between the two sides were not statistically significant, nor for canines' difference (P = .0817), for molars (P = .1105) or for jugular points (.05871). In the class III group, the differences between the two sides were statistically significant for molars (P = .0019) and jugular points (P = .0031) but not for canines (P = .1158). Comparing the two groups, significant differences were found only for incisors' midline deviation (P = .0343) and canine (P = .0177)., Conclusion: The study of the yaw on CBCT should be integrated into three-dimensional cephalometry and could help in differentiating the various malocclusion patterns., (© 2023 The Authors. Orthodontics & Craniofacial Research published by John Wiley & Sons Ltd.)

Objective: To compare the position and shape of the temporomandibular joint (TMJ) articular disc among the sagittal and vertical skeletal patterns in Angle Class III, Class III subdivision malocclusion and normal occlusion. The null hypothesis was that there was no difference in disc position and shape in different (1) malocclusions and (2) skeletal patterns., Methods: This cross-sectional observational study evaluated 105 patients divided into 3 groups: Class III (33, 9.39 ± 1.96 years), Class III subdivision (45, 9.51 ± 1.59 years) and a normal occlusion (27, 10.24 ± 0.87 years) was included as healthy control. Severity of the maxilla-mandibular anteroposterior discrepancy and vertical facial pattern were determined using 2D cephalometry, and the position and shape of the articular discs were evaluated in magnetic resonance images. Statistical parametric and non-parametric tests and Kappa analysis for intra-observer and inter-observer assessment were used (p ≤ .05)., Results: Significant between-group differences were found in articular disc position. In the normal occlusion group, all the articular discs were well positioned. In Class III and Class III subdivision, the discs were displaced in 30.3% and 12.2% of the TMJs, respectively. Sagittal and vertical skeletal patterns did not affect the findings significantly. The Class III subdivision malocclusion group is probably different from the other groups, showing 97.7% of biconcave discs in both TMJs., Conclusion: The longitudinal follow-up of this sample becomes relevant as the two groups with malocclusion in the pre-peak phase of pubertal growth showed differences in the prevalence of displacement and form of the articular disc, with no association with their vertical facial characteristics., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Skeletal Class III malocclusion with maxillary deficiency is a severe maxillofacial disease with unclear pathogenic mechanisms. We recruited a Han Chinese family who was clinically diagnosed with skeletal Class III malocclusion and maxillary deficiency. Using whole exome sequencing, a missense variant in ADAMTS2 (NM&#95;014244: c.3506G>T: p.G1169V) was identified and predicted as deleterious by in silico tools. We also found ADAMTS2 variants associated with deficient maxillary development in a cohort. ADAMTS2 expression in HEK293 cells showed significant decrease due to the variant, which was also consistent in dental pulp stem cells from the proband and a healthy control. In the adamts2-knockdown zebrafish model, the length and width of the ethmoid plate, as well as the length of the palatoquadrate became significantly shorter than the control group (p < 0.001), while there was no significant difference in the length and width of the mandible. The expression of Sox3, which was required in early embryonic craniofacial development, was significantly downregulated in the adamts2-knockdown zebrafish embryos. Bioinformatic and cellular studies showed that the decreased expression of ADAMTS2 may inhibit downstream ErbB signaling pathway transduction and restrain subsequent osteogenesis in human adult mesenchymal stromal cells. Collectively, these data showed that ADAMTS2 (c.3506G>T: p.G1169V) may confer susceptibility to risk of skeletal Class III malocclusion with maxillary deficiency.

The aim of our study was to compare soft tissue measurements with 3D imaging methods in individuals with untreated skeletal and pseudo-Class III malocclusions. The study sample consisted of 75 patients (38 males, 37 females, mean age 12.41 ± 2.35 years) with pseudo- and true skeletal Class III malocclusions and skeletal Class I malocclusions. Soft tissue evaluations of all patients were performed using 3D stereophotogrammetric facial images. In our study, 26 landmarks, 17 linear measurements, 13 angular measurements, and 5 volume measurements were made using the 3dMD Vultus software. The significance was determined to be p < 0.05 in ANOVA, Tukey tests. No significant differences were found among the groups in terms of demographic data (p > 0.05). The skeletal Class I control group had a significantly more extended upper lip and vermillion length as compared to the Class III groups. The soft tissue convexity angle and upper nasal angle were found to be wider in the Class III malocclusion group compared to those in the Class I control group. While the pseudo-Class III group had a significantly lower midface volume, chin volume was significantly higher in the skeletal class group. Upper lip volume was significantly higher in the Class I group. Using 3dMD for guiding clinicians in the differential soft and hard tissue diagnosis of pseudo-Class III malocclusions, differences were revealed in Class I patients in the middle part of the face. In the differential diagnosis of true Class III malocclusions, chin volume was found to be different from that of Class I patients.

Introduction: By means of orthopedics, orthognathic surgery or orthodontics, the management of the maxillary transverse defisciency is a key element of the orthodontic treatment plan, and the guarantee of its stability. the following work aims to support, through a clinical case, the management and the progression of the treatment of the maxillary transverse deficiency associated to a class III skeletal anomaly., Observation: The authors report the case of a 15-year-old patient with a severe class III    malocclusion, with severe maxillary transverse deficiency. The objectives of the treatment were, first, to solve the transverse disharmony by surgically assisted rapid maxillary expansion (SARME), then, secondly, to remove the dentoalveolar compensations and a bimaxillary orthognathic surgery, was carried out to correct the sagittal and vertical disharmony., Conclusion: Surgically assisted rapid maxillary expansion (SARME) appears to be advantageous, both functionally and aesthetically to overcome transverse maxillary deficiency. The agreement between the orthodontist, the maxillofacial surgeon and / or the plastic surgeon, both in the schedule and in the choice of surgical interventions, remains decisive concerning ortho-surgical treatments.

Objective: The aim of this investigation was to analyze the effects of RME and FM on the airway dimensions in Class III patients compared with untreated controls., Methods: A sample of 47 Class III patients treated with RME and FM was analyzed. The treated group was compared with 18 untreated controls. Lateral cephalograms for each patient at T1, T2, and T3 were digitized., Results: At long-term evaluation a significant increase in airway size and a significant decrease in adenoid size were found in the treated group as well as an improvement in the pharynx dimension. During active treatment the treated group showed a significant improvement in lower airway size and in lower pharynx dimension. A significant decrease in adenoid size was also found., Conclusion: The treatment with RME and FM produced favorable stable changes in the airway dimensions in Class III subjects when compared with untreated controls., Competing Interests: Declaration of competing interest The authors have no competing interests., (Copyright © 2019. Published by Elsevier B.V.)

This study focus on the changes of the position and morphology of jaw and condyle after MEAW (the multiloop edgewise arch wire) treatment in adults with a nonlow angle (mean angle or high angle SN - MP > 27°) of skeletal class III (mild to moderate skeletal classs III means -5° < ANB < 0°) malocclusions measured by CBCT (cone beam computed tomography). Twenty adult patients (aged 17-26) with a nonlow angle of skeletal class III malocclusions were selected in this study taken orthodontic treatment by MEAW. CBCT was taken before and after the treatment to analyze the changes of the jaw and condyle. After treatment, the angle of L7-MP decreased 12.2°, L6-MP decreased 10.5°, L1-MP decreased 8.8° ( P < 0.001 for each) and U1-SN increased ( P < 0.05). There was no significant changes between anterior and posterior APDI index and between anterior and posterior spaces of the TMJ (temporomandibular joint) ( P > 0.05). The linear ratio of the TMJ was the LR > 12 before treatment, while it was -12 < LR < 12 after treatment; however, there was no statistically significant difference between them ( P > 0.05). There was also no significant change in anterior and posterior position and morphology of the condyle within the joint fossa after the treatment by MEAW in this study. MEAW technology in correcting the class III with nonlow angle patients mainly relies on the compensation of distally and posterior mandibular teeth, rather than the mandible and condyle moving backward to establish a neutral occlusal. This study was approved by the institutional ethics committee of the Second Hospital of Tianjin Medical University (No. KYJJ2013002)., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Yi Guo et al.)

Objective: To evaluate skeletal and dental changes in patients with skeletal Class III malocclusion and facial asymmetry after surgical-orthodontic treatment using cone-beam computerized tomography (CBCT)., Methods: This study included forty adult patients diagnosed with skeletal Class III malocclusion and asymmetry who underwent either isolated mandibular surgery or bimaxillary surgery. CBCT scans were taken before treatment (T0), at the completion of presurgical orthodontic treatment (T1) and after treatment (T2). Mimics 17.0 and 3-Matics 7.0 were used to measure skeletal and dental parameters. Skeletal and dental changes within each group from pretreatment to posttreatment were assessed, and Pearson correlation analysis was used to analyze the correlations among skeletal changes., Results: The three-dimensional changes in condylar position were insignificant after surgical-orthodontic treatment in either group (P > 0.05). However, in the one-jaw surgery group, there were significant backward rotations of the condyle and ramus on the nondeviated side (P < 0.05), and the condyle on the deviated side rotated inward and forward significantly in the two-jaw surgery group (P < 0.05) at T2. There were no significant differences in the changes in the total alveolar bone thickness of bilateral first molars during dental decompensation (P > 0.05). The ratio between the buccal and the total bone thickness around the maxillary first molar on the deviated side decreased significantly at T1, as did those around the mandibular first molar on the nondeviated side (P < 0.05)., Conclusions: Condylar angulations were less stable after treatment (7 to 9 months after surgery) in both the one-jaw and the two-jaw surgery groups, while condylar displacements were insignificant. In addition, orthodontists should keep a watchful eye to the relative position of the root in the alveolar bone during tooth decompensation.

Introduction: The treatment options for adults with increased overbite are limited to dentoalveolar changes that camouflage the condition. Because of high relapse tendency, defining the problem area is important when creating a treatment plan. This study aimed to evaluate dentoskeletal morphology in skeletal Class I and II anomalies associated with Angle Class I, Class II Division 1 (Class II/1), and Class II Division 2 (Class II/2) malocclusions with increased overbite compared with normal occlusion., Methods: Pretreatment cephalograms of 306 patients (131 men, 175 women; overall ages 18-45 years) were evaluated. Four groups were constructed. Three groups had increased overbite (>4.5 mm): group 1 (n = 96) skeletal Class I (ANB = 0.5°-4°), group 2 (n = 85) skeletal Class II (ANB >4.5°) with Class II/1; and group 3 (n = 79) skeletal Class II with Class II/2 malocclusion. Group 4 as a control (n = 46) skeletal Class I normal overbite. Dental and skeletal characteristics of the groups were compared by sex. For statistical evaluations, analysis of variance followed by Tukey post hoc, Mann-Whitney U, and Kruskall-Wallis tests were used. Additionally correlation coefficients between overbite and skeletal/dental parameters were calculated., Results: Between sexes, with regard to skeletal parameters, the men had greater values in millimetric measurements, and the women had higher SN/GoGn values. Maxillary/mandibular molar heights and the mandibular incisor heights were higher in men. In group 1, decreased lower anterior facial height (LAFH), retrusive mandibular incisors, and increased interincisal degree were determined. The maxillary molars were intrusive, whereas the vertical position of the mandibular molars and incisors in both jaws were normal. In group 2, retrognathic mandible, increased LAFH and mandibular plane angle, extrusive maxillary/mandibular incisors, protrusive mandibular incisors, and decreased interincisal degree were found. In group 3, decreased LAFH, increased interincisal degree, and retrusive incisors in both jaws were determined. There were significant negative correlations between SN/GoGN, palatal plane, and overbite in group 2 and between ANS-SN and overbite in group 3, and positive correlation between interinsical angle and overbite in all increased overbite groups., Conclusions: Dental morphology seems to be the main factor of increased overbite. Differences between groups were related primarily to inclinations and vertical positions of the incisors, rather than molar positions., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Adult orthodontic treatment involving maxillary transverse deficiency is a challenge for an interdisciplinary team. Surgically assisted rapid palatal expansion to segment the maxilla was once the treatment of choice, but the invasiveness, bone deficiency, and gingival recession hindered its acceptance. Corticotomy-assisted rapid maxillary arch expansion with ridge augmentation has the advantage of augmenting alveolar bony housing to accommodate and facilitate tooth movement. This approach was used to correct a severely constricted maxilla with bilateral posterior crossbite and anterior crowding in a 46-year-old man. Treatment time was 14 months. The accelerated arch expansion overcame the crossbite in 7 months, increasing intercanine distance by 5.2 mm and intermolar distance by 9.8 mm. Subsequent implant prosthesis was able to be restored in a functional normal occlusion. Satisfactory and stable clinical outcome was followed for 7 years. Corticotomy-assisted rapid maxillary arch expansion with alveolar bone augmentation is a novel and effective interdisciplinary approach for correcting adult maxillary transverse deficiency. Well controlled prospective clinical trails are warranted for further investigation., (Published by Elsevier Inc.)

Objective: To assess changes in the tongue and hyoid bone positions and airway dimensions after maxillary protraction using lateral cephalograms., Methods: Lateral cephalograms were obtained before (C0) and after (C1) an observation period for untreated children with skeletal Class I malocclusion and before (T0), immediately after (T1), and one year after (T2) maxillary protraction in children with skeletal Class III malocclusion. Cephalometric measurements were compared between the time points in both patient groups., Results: Immediately after maxillary protraction, the tongue moved superiorly and the nasopharyngeal and superior oropharyngeal airway dimensions increased. No significant changes in the middle or inferior oropharyngeal airway dimensions or in the hyoid bone position were noted after treatment., Conclusions: Maxillary protraction improved tongue posture and modified the nasopharyngeal and superior oropharyngeal airway dimensions in patients with skeletal Class III malocclusion. Consequently, maxillary protraction may restore the intra- and extraoral balance and improve respiratory function.

Introduction: Mandibular prognathism (MP) is subject to major polygenic influence and segregates within families in autosomal dominance with variable expressivity and incomplete penetrance. We aimed to identify the inheritance pattern and genes and loci involved in the development of MP in Mediterranean families and to evaluate the dentoskeletal characteristics of affected individuals., Methods: Fifty-one eastern Mediterranean families with individuals affected by MP were identified. Data and biospecimens were collected from 14 of the families, including clinical examination, lateral cephalography (on subjects with Class III malocclusion), and 5 mL blood drawn from consenting affected and nonaffected relatives. Next-generation sequencing (NGS) was performed on 8 families (7 Lebanese, 1 Lebanese/Syrian), including large numbers of affected individuals over many generations and severe conditions, with the use of whole-exome sequencing., Results: Most pedigrees suggested autosomal-dominant inheritance with an equal number of affected male and female individuals. Affected individuals had macrognathic and prognathic mandibles with dentoalveolar compensation. Genetic screening did not correspond with previously reported MP-linked genes, but yielded 3 novel genes (C1orf167, NBPF8, NBPF9) on chromosome 1 potentially responsible for mandibular development and macrognathism., Conclusions: In this first genetic study with the use of NGS on the largest reported number of families with MP, novel genes (C1orf167, NBPF8, NBPF9) were associated with familial MP in the eastern Mediterranean population., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to evaluate the change in three-dimensional morphology and clinical symptoms of temporomandibular joint (TMJ) in class III dentofacial deformity patients postoperatively for 6 months after sagittal split ramus osteotomy (SSRO).Seventeen patients with skeletal Class III malocclusion and 10 asymptomatic volunteers (classified as Control group) were recruited for the study and underwent cone-beam computed tomography scanning. The geometries of the maxilla and mandible were reconstructed using MIMICS (Materialise, Leuven, Belgium). The morphologic measurements of the patients' TMJs were done before surgery and at 6-month follow-up - named as Pre and Post groups, respectively.The joint spaces (medial joint space, superior joint space, lateral joint space, anterior joint space, and posterior joint space) of the Control group were significantly greater than those of the Pre and Post groups (P < .05), and SSRO did not significantly change the TMJ morphology parameters. Five patients were found to have preoperative temporomandibular disorder (TMD) symptoms, and 3 of them were relieved at 6 months after surgery. Postoperative TMD symptom was observed in 1 patient without preoperative TMD symptom.SSRO did not markedly alter the TMJ morphology of the patients with mandibular prognathism. The effects of SSRO on TMD symptoms should be related to the type of deformity.

The aim of the study was to investigate how to improve the forecasting of craniofacial unbalance risk during growth among patients affected by Class III malocclusion. To this purpose we used computational methodologies such as Transductive Learning (TL), Boosting (B), and Feature Engineering (FE) instead of the traditional statistical analysis based on Classification trees and logistic models. Such techniques have been applied to cephalometric data from 728 cross-sectional untreated Class III subjects (6-14 years of age) and from 91 untreated Class III subjects followed longitudinally during the growth process. A cephalometric analysis comprising 11 variables has also been performed. The subjects followed longitudinally were divided into two subgroups: favourable and unfavourable growth, in comparison with normal craniofacial growth. With respect to traditional statistical predictive analytics, TL increased the accuracy in identifying subjects at risk of unfavourable growth. TL algorithm was useful in diffusion of information from longitudinal to cross-sectional subjects. The accuracy in identifying high-risk subjects to growth worsening increased from 63% to 78%. Finally, a further increase in identification accuracy, up to 83%, was produced by FE. A ranking of important variables in identifying subjects at risk of growth worsening, therefore, has been obtained.

Objective: Our aim was to describe hard- and soft-tissue asymmetry in people who have a skeletal Class III malocclusion, and to compare with those without asymmetry. We also performed a regional analysis of a possible correlation between facial soft- and hard-tissue asymmetries., Methods: This retrospective study was performed with the use of the computed tomographic scans of 60 subjects. The skeletal Class III subjects were categorized into 2 subgroups: soft-tissue menton deviation ≤4 mm (n = 20) versus >4 mm (n = 20). The Class III groups were compared with a Class I symmetry group (n = 20). Hard and soft tissues were segmented into different morphologic areas and deviation calculated. Pearson correlation coefficients were obtained, and 1-way analysis of variance was conducted for statistical analysis., Results: The highest deviation in the hard tissues of the Class III asymmetry group was in the corpus region (5.55 ± 3.05 mm), with the second highest in the angulus region (4.70 ± 2.43 mm). The highest average deviation in the soft tissues was seen in the lower cheek (7.04 ± 3.46 mm). In the different study groups, the amounts of asymmetry measured in anatomic structures on the mandible were found to be highly correlated between neighboring structures., Conclusions: Clinically and statistically significant differences were found in the anatomic regions located in the middle and lower thirds of the face. There was a medium or high correlation between condyle, coronoid process, ramus, and angulus regions. A low level of correlation was observed between middle face and mandibular asymmetries in hard-tissue upper cheek and lower cheek regions were correlated with different mandibular regions., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to examine changes in masseter and medial pterygoid muscles, ramus, condyle and occlusal force after bi-maxillary surgery in class II and III patients., Subjects and Methods: The subjects were 42 patients (84 sides) who underwent sagittal split ramus osteotomy with Le Fort I osteotomy (21 class II cases: mandibular advancement and 21 class III cases: mandibular setback). The cross-sectional measurements of the masseter and medial pterygoid muscles, ramus and condyle were measured in horizontal plane images by computed tomography (CT), before and 1 year after the operation. Occlusal force and contact area were also recorded before and 1 year after the operation., Results: Preoperatively, class II was significantly larger than class III in masseter width (P = 0.0068), masseter area (P < 0.0001) and medial pterygoid length (P < 0.0001). However, class II was significantly smaller than class III in medial pterygoid width (P < 0.0001). After 1 year, class II was significantly smaller than class III in masseter length (P = 0.0017). Class II was still larger than class III in medial pterygoid area after 1 year (P = 0.0343). Class II was significantly larger than class III in condylar angle pre-operatively (P < 0.0001) and after 1 year (P = 0.0006). After 1 year, class II decreased significantly more than class III in condylar thickness (P = 0.0020), condylar width (P < 0.0001) and condylar area (P < 0.0001)., Conclusion: This study suggested that changes in the cross-sectional measurements of masseter and medial pterygoid muscles and the condyle differed between class II and class III patients, although occlusal force did not significantly change 1 year after surgery in both groups., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Objectives: To clarify the associations among tongue volume, hyoid position, airway volume and maxillofacial form using cone beam computed tomography (CBCT) data for children with Class-I, Class-II and Class-III malocclusion., Setting and Sample Population: Sixty children (mean age, 9.2 years) divided into Class-I, Class-II and Class-III malocclusion groups according to the A-nasion-B angle., Material and Methods: Cone beam computed tomography was used for three-dimensional reconstruction of the maxillofacial region and airway. The hyoid position and the tongue, airway and oral cavity volumes were evaluated. Upper airway ventilation status was calculated using computational fluid dynamics. The groups were compared using analysis of variance and Kruskal-Wallis tests; relationships among the parameters were assessed using Pearson's and Spearman's rank correlation tests., Results: The tongue volume was larger in Class-III patients (50.63 cm 3 ) than in Class-I patients (44.24 cm 3 ; P < 0.05). The hyoid position was lower (49.44 cm), and anatomical balance (AB; tongue volume/oral cavity volume; 85.06%) was greater in Class-II patients than in Class-I patients (46.06 cm, 80.57%, respectively; P < 0.05 for both). The hyoid height showed a positive correlation with AB (r = 0.614; P < 0.001)., Conclusions: Children with Class-III malocclusion have large tongue volumes and small AB; the reverse is true for children with Class-II malocclusion. The hyoid position is closely associated with AB in children with malocclusion., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: The purpose of this study was to examine the relationship between occlusal force and condylar morphology in class II and III after sagittal split ramus osteotomy (SSRO) with Le Fort I osteotomy., Materials and Methods: The subjects were 42 female patients who underwent bi-maxillary surgery, and were divided into 2 groups (21 class II and 21 class III cases). They were selected randomly from among patients that underwent surgery from 2012 to 2017. Condylar height, ramus height, ramus inclination and condylar square were assessed by computed tomography (CT), preoperatively and 1 year postoperatively. Occlusal contact area and occlusal force were measured pre- and 1, 3, 6 and 12 months post-operative., Results: Condylar height and ramus height of the class II advancement cases decrease more significantly than those of class III. There were no significant differences in time-course changes of occlusal force and area between the class II and III. In the class II cases, occlusal force at 1 and 3 months was significantly lower than the preoperative value (P = 0.0009, P = 0.0002). On the other hand, in class III, occlusal force at 1, 3 and 6 months (P = 0.0038, P = 0.0031, P = 0.0283) was significantly lower than the preoperative value., Conclusion: This study suggested that occlusal force of the class II advancement cases reached the pre-operative level earlier than that of the class III setback cases, even though condylar height decreased after surgery in the class II cases. However, a correlation between occlusal force change and condylar height reduction after surgery could not be found., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: One of the most controversial issues in treatment planning of class III malocclusion patients is the choice between orthodontic camouflage and orthognathic surgery. Our aim was to delineate diagnostic measures in borderline class III cases for choosing proper treatment., Methods: The pretreatment lateral cephalograms of 65 patients exhibiting moderate skeletal class III were analyzed. The camouflage group comprised of 36 patients with the mean age of 23.5 (SD 4.8), and the surgery group comprised of 29 patients with the mean age of 24.8 years (SD 3.1). The camouflage treatment consisted of flaring of the upper incisors and retraction of the lower incisors, and the surgical group was corrected by setback of the mandible, maxillary advancement, or bimaxillary surgery. Mann-Whitney U test was used to compare the variables between the two groups. Stepwise discriminant analysis was applied to identify the dentoskeletal variables that best separate the groups., Results: Holdaway H angle and Wits appraisal were able to differentiate between the patients suitable for orthodontic camouflage or surgical treatment. Cases with a Holdaway angle greater than 10.3° and Wits appraisal greater than - 5.8 mm would be treated successfully by camouflage, while those with a Holdaway angle of less than 10.3° and with Wits appraisal less than - 5.8 mm can be treated surgically. Based on this model, 81.5% of our patients were properly classified., Conclusions: Holdaway H angle and Wits appraisal can be used as a critical diagnostic parameter for determining the treatment modality in class III borderline cases.

Purpose: Maxillary downgraft (MD) and mandibular setback (MS) are problematic procedures in terms of postoperative stability. While the amount of intraoperative clockwise rotation (CWR) of the proximal segment (PS) after MS combined with MD has a positive correlation with the amount of MD, mandibular relapse after MS with MD in relation to intraoperative CWR of the PS has not been reported. Moreover, the effect of mandibular relapse on maxillary stability after MS with MD remains unclear. The purpose of this study is to evaluate mandibular and maxillary stability after MS with MD in relation to intraoperative CWR of the PS and amount of MD., Materials and Methods: The study included 57 patients who underwent bimaxillary orthognathic surgery. Patients were classified into two groups according to whether MD was performed or not performed: Group I had 2 mm or more MD; and Group II had less than 2 mm MD including vertical impaction or no vertical changes. The amount of surgical movement and postoperative relapse were cephalometrically evaluated and statistically analyzed., Results: There was no significant difference in MS between Groups I and II, however, the vertical movement of the maxilla was different significantly (p < 0.001). In Group I, the intraoperative CWR and postoperative CCWR of the PS was greater than that of Group II (p = 0.010; p < 0.001, respectively). Consequently, the anterior relapse of the mandible was greater in Group I than in Group II despite the same amount of MS in Groups I and II. In Group I, with direct bone contact using Le Fort I inclined osteotomy, vertical relapse at point A showed no statistical correlation with anterior relapse at point B, while the vertical and horizontal dental relapse at U1 showed significant correlations with anterior relapse at point B (r = -0.403, p = 0.030; r = 0.581, p < 0.001, respectively)., Conclusion: For more stable results, Le Fort I inclined osteotomy is recommended to obtain direct bone contact when moving the maxilla inferiorly. The PS must also be fixed while maintaining vertical bone step to prevent CWR., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Objective: The aim of this study was to evaluate and compare the mandibular arch posterior space changes in Class III patients treated with facemask (FM) with removable upper appliance or modified tandem traction bow appliance (MTTBA)., Methods: Pre- and post-treatment and pre- and post-observation lateral cephalograms of 76 subjects with skeletal and dental Class III malocclusion from the period 2000-10 years formed the materials of this study. In the first group, 25 patients (10 girls, 15 boys; mean age: 10 years, 1 month) were treated with MTTBA. The average treatment time was 12 months. In the second group, 26 patients were treated (13 girls, 13 boys; mean age: 10 years, 4 months) with a Delaire-type FM. The average treatment time was 13 months. The remaining 25 children (9 girls, 16 boys; mean age: 9 years, 8 months) were observed without treatment for 10 months. ANOVA, Duncan, and paired t-tests were used for statistical evaluation., Results: Although ramus width and mandibular posterior space increased significantly in all groups, no significant differences were found among the groups. Significant increase in tipping of lower molar (L6/GoMe) in the MTTBA group showed a significant difference compared with the FM and control groups. Significant retroclination of the lower incisors (L1/NB) in the MTTBA and FM treatment groups was significantly different compared with the control group. Retroclination of lower incisors in the MTTBA group was significantly greater than that in the FM group., Conclusions: FM and MTTBA treatment approaches did not affect the dimensions of posterior space., Limitations: To generalize the results of this study, long term evaluation by considering the third molar position should be done.

Aim: The study was conducted to assess facial asymmetry in various dental malocclusions and to determine asymmetry in lower, mid, and upper face and jaws using posteroanterior cephalometric analysis., Materials and Methods: Overall, 120 posteroanterior cepha-lograms were taken of individuals between 12 and 25 years of both sexes, and were divided into four groups: Angle's class I excellent occlusion, Angle's class I malocclusion, Angle's class II malocclusion, and Angle's class III malocclusion. These cepha-lograms were traced and Grummon's analysis was performed., Results: In Angle's class I occlusion and Angle's class II malocclusion, the results obtained showed asymmetry present in the upper face. Correlation was found between occlusion, maloc-clusion, and facial asymmetry., Conclusion: Facial asymmetry was found in all dental occlusions whether excellent or malocclusion group, with maximum asymmetry having upward trend toward upper face starting from lower., Clinical Significance: For the success of the orthodontic treatments in various types of malocclusion and to determine the facial asymmetry, posteroanterior view can be very helpful, as it gives additional information which can be utilized to augment treatment planning and improve prognosis in terms of relapse prevention.

Purpose: The purpose of this study was to compare time-course changes in temporomandibular joint (TMJ) space between mandibular advancement surgery and setback surgery after sagittal split ramus osteotomy (SSRO) and Le Fort I osteotomy., Subjects and Methods: The subjects were 46 patients (92 joints) who underwent bi-maxillary surgery. The TMJ disc position was assessed by magnetic resonance imaging (MRI) and the anterior, superior, posterior, medial and lateral joint spaces were assessed by computed tomography (CT), preoperatively and at 1 week and 1 year postoperative. The 92 joints were divided into 2 groups, namely class II (n = 46 joints), and class III (n = 46 joints) (an advanced group vs a setback group). Next, the 92 joints were divided into 2 groups comprising 36 joints with anterior disc displacement joint (ADD group) and 56 joints without (non-ADD group). Time-course changes in the measurements were compared statistically between the advanced and setback groups, and between the ADD and non-ADD groups., Results: There were no significant differences between the advance group and setback group regarding time-course change in all the joint spaces. However, there were significant differences between the ADD group and non-ADD group regarding time-course change in the medial, anterior, superior and posterior joint spaces (P < 0.05)., Conclusion: This study suggested that ADD could affect the time-course change in TMJ space and condylar position after bi-maxillary osteotomy., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: The purpose of this study was to determine and compare the shapes, sizes, and bridging of the sella turcica in patients with different skeletal patterns and genders., Methods: It was a cross-sectional comparative study. The samples were divided into three groups according to the skeletal pattern viz. Class I, Class II and Class III, and each group consisted of 40 samples (20 males and 20 females). The lateral cephalograms were traced and the sella turcica was assessed for its size, shape, and bridging., Results: The mean length, anteroposterior diameter and depth of sella turcica were 8.13 ± 2.03 mm, 9.60 ± 1.43 mm and 6.40 ± 1.21 mm respectively. The mean length of sella turcica was 7.91 ± 1.52 mm in Class I, 7.32 ± 1.62 mm in Class II and 9.16 ± .2.42 in Class III skeletal pattern; anteroposterior diameter was 9.30 ± 1.02 mm in Class I, 9.15 ± 1.28 mm in Class II and 10.35 ± 1.64 mm in Class III skeletal pattern; and the depth was 6.40 ± 0.92 mm in Class I, 6.07 ± 1.01 mm in Class II and 6.74 ± .1.54 mm in Class III skeletal pattern. There were significant differences in length and anteroposterior diameter and sella turcica between Class I, Class II and Class III skeletal patterns (p = 0.01), (p = 0.01) respectively. There was no significant difference in size of sella turcica between different genders and age groups. Sixty percent of the patients studied had normal Sella morphology. Partial Sella turcica bridging and Sella turcica bridging was seen in this study in 23.33% and 11.67% of patients respectively., Conclusion: Sixty percent of the patients had normal sella turcica. There were significant differences in lengths and anteroposterior diameters among Class I, Class II and Class III patients. The larger size was present in skeletal Class III patients.

Objectives: The present study aimed to compare the amount of incisal tooth wear in the maxillary central incisors of patients with skeletal Class III malocclusion and anterior crossbite receiving one-phase or two-phase treatment. The hypothesis was that tooth wear would differ according to treatment modalities., Materials and Methods: Maxillary dental casts obtained before (T1) and after (T2) orthodontic treatment were divided into three groups. Group I consisted of casts from 21 patients (7 males, 14 females; mean age 9.8 years) who received two-phase treatment (maxillary protraction followed by fixed appliance therapy). Group II comprised casts from 37 patients who underwent orthodontic camouflage treatment for crossbite, subdivided according to age. Group IIa consisted of casts from 15 adolescents (8 males, 7 females; mean age 13.5 years), and group IIb consisted of casts from 22 adults (13 males, 9 females; mean age 24.5 years). Maxillary dental casts obtained at T1 and T2 were scanned. For each pair of digital images, T2 was superimposed on T1 using the best-fit method. Tooth wear was quantified and compared among groups., Results: Significantly less tooth wear was observed in group I compared to groups IIa and IIb, but no difference was found between groups IIa and IIb. Spearman correlation analysis revealed no significant correlation between tooth wear and age, treatment duration, or craniofacial morphology., Conclusions: Despite the long duration of early treatment, it caused less wear of the maxillary central incisors than did orthodontic camouflage treatment.

Objectives: To compare the pharyngeal airway dimensions in adults with skeletal Class III malocclusion and well-balanced faces, to ascertain whether sex can influence such measurements and to correlate skeletal pattern with pharyngeal dimensions., Methodology: Fifty adults were recruited and assigned to two groups: skeletal Class III (n = 25; 12 males and 13 females, mean age = 26.1 years), and skeletal Class I (n = 25; 11 males and 14 females, mean age = 26.0 years), with well-balanced faces. Pharyngeal measurements were made using cone beam computed tomography and analyzed with Dolphin Imaging software 11.5., Results: Pharyngeal sagittal area, length, retroglossal area and width were statistically greater for males. Pharyngeal volume was greater for Class III patients (p = .0245), due to enlarged male dimensions. A significant but moderate correlation was observed between pharyngeal airway volume and ANB angle (r = -.4917) and effective mandibular length (Co-Gn, r = .5181)., Conclusion: There is sexual differentiation in the pharyngeal airway morphology for Class III adults. As females present similar pharynx volume compared to a normal skeletal pattern, mandibular setback surgery should be carefully planned because of the risk of airway constriction.

Objectives: To evaluate prevalence, distribution, and sexual dimorphism of dental anomalies (DA) among different skeletal malocclusions (SM) and growth patterns (GP) under the hypothesis that specific clinical patterns exist and may indicate common etiological roots., Materials and Methods: A total of 1047 orthodontic records of patients older than 8 years were evaluated. The SN-GoGn angle was used to classify GP (hypodivergent, normal, and hyperdivergent), and the ANB angle was used to verify SM (Angle Classes I, II, and III). These assessments were done from lateral cephalometric radiographs. DA were diagnosed using panoramic radiographs by one calibrated investigator. Odds ratios, chi-square, and Student's t-tests were used., Results: Of the subjects, 56.7% were female, with mean age of 16.41 (±10.61) years. The prevalence of DA was 15.7%. Impaction and tooth agenesis were the most prevalent DA, with relative frequencies of 14.4% and 9.7%, respectively. DA were most prevalent in Class III SM (80.8%) and in hypodivergent GP (82.5%), although this was not statistically significant. Tooth agenesis ( P < .01) and microdontia ( P = .025) were significantly more common among hypodivergent GP and Class III SM, respectively., Conclusions: The results of this study support the idea that DA are preferentially associated with certain patterns of malocclusion.

Objectives: This study investigated the long-term vertical skeletal changes induced by facemask therapy in patients with Class III malocclusion and different vertical skeletal patterns., Materials and Methods: A total of 54 patients (20 boys and 34 girls; mean age, 7.7 ± 2.0 years) with Class III malocclusion who were successfully treated with facemask therapy were included in this study. Vertical skeletal changes (overbite depth indicator, angle between the Sella-Nasion (SN) plane and Gonion-Gnathion (GoGn) line, angle between the Frankfort horizontal (FH) plane and mandibular plane, gonial angle, and angle between the SN plane and palatal plane) were measured on lateral cephalograms from before treatment (T0) to after facemask therapy (T1) and from T0 to after retention (T2). Multivariate linear regression analysis was used to study the associations of the patients' skeletal patterns with the short-term (T0-T1) and long-term (T0-T2) vertical skeletal changes as a result of facemask therapy., Results: The mean treatment period of facemask therapy (T0-T1) was 1.4 ± 0.6 years, and the mean retention period (T1-T2) was 6.9 ± 2.6 years. Age at T0 was significantly correlated with vertical skeletal changes from T0 to T1. Differences in the treatment results between sexes were not significant. The angle between point A-point B line and mandibular plane to mandibular plane angle at T0 and the angle between the FH plane and mandibular plane at T0 were significant predictors for short-term and long-term changes. Changes in the Sella-Nasion-point A from T0 to T1 and from T1 to T2 significantly affected vertical changes in the short term and long term, respectively., Conclusions: Vertical skeletal changes as a result of facemask therapy are significantly associated with severity of the skeletal Class III malocclusion and mandibular plane angulation before treatment and the amount of forward maxillary growth during the treatment and retention periods.

Introduction: The purpose of this study was to describe the skeletal and dentoalveolar changes in a group of growing skeletal Class III patients treated with hybrid rapid palatal expansion and facemask., Methods: Twenty-eight growing patients with skeletal Class III malocclusion were treated using a rapid maxillary expander with hybrid anchorage according to the ALT-Ramec protocol (SKAR III; E.P.), followed by 4 months of facemask therapy. Palatal miniscrew placement was accomplished via digital planning and the construction of a high-precision, individualized surgical guide. Pretreatment and posttreatment cephalometric tracings were analyzed, comparing dental and skeletal measurements., Results: Point A advanced by a mean of 3.4 mm with respect to the reference plane Vert-T. The mandibular plane rotated clockwise, improving the ANB (+3.41°) and the Wits appraisal (+4.92 mm). The maxillary molar had slight extrusion (0.42 mm) and mesialization (0.87 mm)., Conclusions: The use of a hybrid-anchorage expander followed by 4 months of facemask treatment improves the skeletal Class III relationship with minimal dental effects, even in older patients (mean age, 11 years 4 months, ± 2.5 years)., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: To investigate the association between the periodontal soft tissue, alveolar bone and dental parameters surrounding the incisors at baseline in patients with skeletal Class III malocclusion., Materials and Methods: The study sample comprised 154 teeth from 28 patients with skeletal Class III malocclusion (19 men and 9 women, 21.15 ± 4.02 years). Periodontal soft tissue examination and hard tissue measurements with cone-beam computed tomography (CBCT) were performed. Factor analysis was used to reduce the CBCT variables, and correlation analysis between the hard tissue factors and soft tissue parameters was performed. Differences in hard tissue parameters between thick and thin gingival types were evaluated., Results: CBCT measurements were reduced to three hard tissue factors: lingual plate, coronal-buccal plate, and apical-buccal plate. Keratinized gingiva width and thickness were positively correlated with the coronal-buccal plate factor and negatively correlated with the apical-buccal plate factor. In the thin gingival biotype, mandibular incisors were more proclined, and the apical part of the buccal alveolar plate and the coronal part of lingual alveolar plate were thicker than in the thick gingival biotype., Conclusions: In the anterior teeth in cases of skeletal Class III malocclusion, hard tissue structures on the buccal side can be grouped based on coronal and apical factors that are significantly correlated with keratinized gingival width and thickness. Thick and thin gingival biotypes exhibited differences in tooth inclination and alveolar plate thickness with regard to the mandibular incisors.

Purpose: This study was aimed to evaluate the nasal deviation in patients with asymmetric mandibular prognathism., Materials and Methods: Thirty-five patients with skeletal class III malocclusion were included in the study. Significant mandibular asymmetry of >4 mm menton deviation in three-dimensional (3D) reformatted cone beam computed tomography images was defined as asymmetry group (n = 20). Patients without mandibular asymmetry served as control group (n = 15). The mandibular asymmetry was evaluated pre- and postoperatively., Results: Nasal tip was significantly shifted to the deviated side of the mandible (short side) in the asymmetry group, as compared to the control group (1.5 ± 0.9 degree, P < 0.01). Alar base angle (ABA) was significantly narrower in nondeviated side (long side) than in the deviated side in asymmetry group. However, control group showed no bilateral difference in ABA. Correction of deviated mandibular prognathism by isolated mandibular surgery resulted in change in the ABA but not the columella base position or nasal asymmetry. ABA on nondeviated side significantly decreased in proportion to the amount of transverse menton movement by surgery (r = -0.560, P < 0.01)., Conclusion: Our results showed that mandibular chin deviation was accompanied by nasal deviation. Isolated mandibular surgery can potentially influence the alar base position on the contralateral side of deviation but not the nasal tip asymmetry. Therefore, clinicians should inform patients preoperatively of the fundamental limitation of mandibular surgery in cases with preexisting nasal asymmetry.

Introduction: The aim of this study was to assess the 3-dimensional soft tissue changes in growing Class III patients with maxillary deficiency associated with 2 bone-anchored maxillary protraction protocols in relation to an untreated control group of Class III patients., Methods: Growing skeletal Class III patients between the ages of 10 and 14 years participated in this study. In group 1 (n = 10), skeletally anchored facemasks were used with miniplates placed at the zygomatic buttress. In group 2 (n = 10), the patients were treated with Class III elastics extending from infrazygomatic miniplates in the maxilla to symphyseal miniplates in the mandible. Group 3 (n = 10) was an untreated control group. Three-dimensional stereophotogrammetry images were acquired before and after treatment, and then superimposed and analyzed. In addition, lateral cephalometric radiographs were analyzed., Results: The maxilla moved forward significantly in groups 1 and 2 compared with the untreated control group (group 1, 4.87 mm; group 2, 5.81 mm). The 3-dimensional soft tissue analysis showed significant treatment effects; the major changes were observed in the upper lips, cheeks, and middle of the face, which had a significant positive sagittal displacement in both treatment groups. The lower lip and chin area showed significant negative sagittal changes that indicated that the soft tissue growth in this area was restrained with backward displacement especially in group 1 more than in group 2., Conclusions: The 2 bone-anchored maxillary protraction protocols effectively improved the Class III concave soft tissue profile., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the relationship between anterior occlusion and frontal sinus size., Methods: The patient database at the Eastman Institute for Oral Health, University of Rochester, was searched for male patients older than 15 years and females older than 13 years of age. After applying inclusion and exclusion criteria, participants' photos and lateral cephalometric and posteroanterior radiographs were examined then classified into a control class I group (n = 20, 15.7 ± 2.7 years) and eight malocclusion groups (n = 136, 16.1 ± 2.1 years). The frontal sinus area on the lateral cephalometric radiograph and on the posteroanterior radiograph were measured and compared between groups., Results: One-way analysis of variance demonstrated a significant difference among all nine groups (P = .0001). Pairwise comparison showed a significant difference between the class I group and all other malocclusion groups (P < .05) except the edge-to-edge group for both radiographs and except the bimaxillary protrusion group for the lateral cephalometric radiographs. Tukey's method was not able to demonstrate a significant difference among the subgroups of skeletal malocclusions (P > .05). Linear regression analyses with stepwise model selection demonstrated that anterior cranial base, mandibular plane angle, and upper incisor inclination commonly have a significant effect on frontal sinus size., Conclusion: The frontal sinus size could be used as an indicator of harmonious anterior occlusion. There were no differences among the subgroups of each skeletal malocclusion. The anterior cranial base, facial height, and maxillary incisor inclination appear to have a significant effect on frontal sinus size.

Introduction: We investigated the long-term success of orthopedic treatment in skeletal Class III malocclusions, established a model to predict its long-term success, and verified previously reported success rates and prediction models., Methods: Fifty-nine patients who underwent successful facemask treatment and were followed until growth completion were evaluated. After completion of growth, the patients were divided into successful and unsuccessful groups according to overjet, overbite, and facial profile. Pretreatment cephalometric measurements were compared between groups, and logistic regression analysis was used to identify the predictors of long-term success. Four previously published articles were selected to verify the success rate and predictability of the prediction models with regard to our patient sample., Results: The treatment success rate was 62.7%. The AB-mandibular plane angle, Wits appraisal, and the articular angle were identified as predictors. The success rates differed according to success criteria and patient characteristics. The prediction models proposed by the 4 previous studies and our study showed similar predictabilities (61.0%-64.4%) for our patient sample. The predictability for the unsuccessful group was low., Conclusions: Our results suggest that no particular method or factor can predict the long-term success of orthopedic treatment for skeletal Class III malocclusion., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

This study aimed to describe the condylar layer and cartilage island in subjects with unilateral condylar hyperplasia (UCH). Five individuals (15-18 years old) with a diagnosis of UCH, treated in a university hospital in Temuco, Chile, were included. The analysis examined the presence, extension, and thickness of the layers on the condylar surface, the number, depth, and area of the cartilage islands, and the argyrophilic proteins of the nucleolar organizer region (AgNOR) score. Statistical significance was set at P<0.05. The fibrocartilaginous layer was thickest (0.13±0.05mm) and the joint layer was thinnest (0.07±0.01mm) (P<0.05). With respect to the number, depth, and area of the islands, case 1 presented the highest values, followed by case 2; the cartilage island was related to the fibrocartilaginous layer (P<0.05). All cases had AgNOR proteins in the proliferative and fibrocartilaginous layers, as well as the islands with the greatest presence of chondrocytes (P=0.245). A relationship was observed between the histopathological alterations in the different layers on the condylar surface and the thickness of the fibrocartilaginous layer, as well as the thickness of the latter and the number, depth, and area of the cartilage islands in the trabecular bone., (Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Introduction: The purposes of this study were to identify buccolingual inclinations and alveolar bone thickness in patients with Class III dentofacial deformities and to compare these measurements with those from subjects with normal occlusions to verify, based on the correlation between these 2 variables, whether the natural process of bone remodeling provides uniformity of bone thickness or whether it varies around the roots due to tooth inclination., Methods: The sample consisted of 35 adults with normal occlusions and 35 adults with Class III dentofacial deformities with no previous orthodontic treatment. Buccolingual inclinations and alveolar bone thickness were measured at 3 heights from the cementoenamel junction from 3-dimensional images generated by cone-beam computed tomography., Results: The region corresponding to the maxillary canines appeared to be thinner, and the palatal area of the maxillary central incisors and the distobuccal region of the mandibular second molars appeared to be thicker. Greater tooth inclinations were observed in the maxillary incisors and mandibular canines, and smaller tooth inclinations were observed on the buccal roots of the mandibular second molars., Conclusions: In subjects with Class III deformities, more statistically significant correlations were found between inclination and thickness in the mandibular teeth, whereas in subjects with normal occlusion, few statistically significant correlations were found between these 2 variables., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The purpose of this study was to clarify the relationships between upper airway factors (nasal resistance, adenoids, tonsils, and tongue posture) and maxillofacial forms in Class II and III children., Methods: Sixty-four subjects (mean age, 9.3 years) with malocclusion were divided into Class II and Class III groups by ANB angles. Nasal resistance was calculated using computational fluid dynamics from cone-beam computed tomography data. Adenoids, tonsils, and tongue posture were evaluated in the cone-beam computed tomography images. The groups were compared using Mann-Whitney U tests and Student t tests. The Spearman rank correlations test assessed the relationships between the upper airway factors and maxillofacial form., Results: Nasal resistance of the Class II group was significantly larger than that of the Class III group (P = 0.005). Nasal resistance of the Class II group was significantly correlated with inferior tongue posture (P <0.001) and negatively correlated with intermolar width (P = 0.028). Tonsil size of the Class III group was significantly correlated with anterior tongue posture (P <0.001) and mandibular incisor anterior position (P = 0.007). Anterior tongue posture of the Class III group was significantly correlated with mandibular protrusion., Conclusions: The relationships of upper airway factors differ between Class II and Class III children., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

We successfully treated a patient with achondroplasia with conventional orthodontic techniques. It was followed by long-term retention. The patient, a 12-year-old boy, had chief complaints of occlusal disturbance and mandibular protrusion. He had been diagnosed with achondroplasia and had growth hormone treatment in his early teenage years. His facial profile was concave with a bulging forehead and a retrognathic maxilla. It was characterized by a skeletal Class III jaw-base relationship with a retropositioned maxilla. At the age of 12 years 9 months, maxillary protraction was initiated with a reverse headgear; for 2 years 6 months, the maxillomandibular growth was controlled. After the growth spurt, at the age of 15 years 6 months, leveling and alignment of both dental arches were started with preadjusted edgewise appliances. After 83 months of multibracket treatment, an acceptable occlusion with a Class I molar relationship and an adequate interincisal relationship was achieved, despite the simultaneous marked vertical growth of the mandible. The resultant occlusion was stable during a 6-year retention period, although considerable forward-downward mandibular growth was observed. Conclusively, our results indicated the necessity of long-term observation in this patient with achondroplasia, especially because of the persistent mandibular growth., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Clinicians are accustomed to viewing conventional two-dimensional (2D) photographs and assume that viewing three-dimensional (3D) images is similar. Facial images captured in 3D are not viewed in true 3D; this may alter clinical judgement. The aim of this study was to evaluate the reliability of using conventional photographs, 3D images, and stereoscopic projected 3D images to rate the severity of the deformity in pre-surgical class III patients. Forty adult patients were recruited. Eight raters assessed facial height, symmetry, and profile using the three different viewing media and a 100-mm visual analogue scale (VAS), and appraised the most informative viewing medium. Inter-rater consistency was above good for all three media. Intra-rater reliability was not significantly different for rating facial height using 2D (P=0.704), symmetry using 3D (P=0.056), and profile using projected 3D (P=0.749). Using projected 3D for rating profile and symmetry resulted in significantly lower median VAS scores than either 3D or 2D images (all P<0.05). For 75% of the raters, stereoscopic 3D projection was the preferred method for rating. The reliability of assessing specific characteristics was dependent on the viewing medium. Clinicians should be aware that the visual information provided when viewing 3D images is not the same as when viewing 2D photographs, especially for facial depth, and this may change the clinical impression., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)

The purpose of this study was to clarify the correlation between pre-treatment anterior disc displacement and mandibular stability after orthognathic and orthodontic treatment among patients with a skeletal class II malocclusion and without pre-treatment condylar resorption. Thirty-seven patients were included (7 male, 30 female). The mean length of follow-up was 6.76±3.06 years. Patients with condylar resorption before treatment were excluded. Magnetic resonance images and lateral cephalometric radiographs were taken before treatment (T0), after treatment (T1), and at follow-up (T2). Patients were classified according to the degree of disc displacement: -10-10° 'normal', 11-50° 'slight to mild', ≥51° 'moderate to severe'. Results showed the condyle moved posterosuperiorly after treatment, and then moved anteriorly to a more concentric location during the long follow-up period. Condylar movement was found not to correlate with disc displacement. The degree of disc displacement before treatment did not correlate with the post-surgical mandibular positional change in either the sagittal or vertical direction. To conclude, the mandibular bilateral sagittal split ramus osteotomy was stable in the long-term after orthognathic and orthodontic treatment. In the absence of pre-treatment condylar resorption, the degree of initial anterior disc displacement did not have a significant influence on the stability of mandibular advancement., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Date of birth: 2/8/1982; sex: male. A., Pretreatment Records: 25 years; 7/3/2008., Diagnosis: Very severe Class III malocclusion in adult dentition in hyperdivergent facial pattern; Sagittal dimension: skeletal and dental Class II, severe alveolar retrusion of the mandibular incisors, negative overjet (-11mm); transverse dimension: Class III-related bilateral crossbite with no transverse maxillary deficiency; vertical dimension: incisor overbite, increased height of the lower facial third; Teeth missing prior to treatment: 16-26., Treatment Plan: Appliances or procedures: multi-bracket bi-maxillary appliance and maxillofacial surgery; arch decompensation; maxillofacial surgery; fixed retainers; beginning of treatment: 26 years; 10/01/2009. B., Posttreatment Records: 17/2/2011; 28 years., Duration of Active Treatment: 25 months., Retention: Maxillary: 17/2/2011; mandibular: 17/2/2011. C. POST-RETENTION RECORDS: (1 year minimum): 25/04/2016; 33 years; duration of retention: lifelong. Post-retention duration: 5years and 2months., (Copyright © 2016 CEO. Published by Elsevier Masson SAS. All rights reserved.)