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Objectives: To evaluate the relationship between the mandibular dental and basal arches using CBCT, and to assess the correlation between basal arch dimensions derived from CBCT and 3-dimensional (3D) virtual models in a cohort sample exhibiting normal occlusions.

Introduction: The purpose of the present study was to use facial axis (FA) points to classify dental arch form generated from an analysis of 3-D virtual models of a sample of normal occlusions. A secondary aim was to introduce a new arch form template based on this classification for clinical application.

Objectives:  The aims of this study were to evaluate posterior maxillary alveolar bone dimensions and to compare these dimensions in males and females., Materials and Methods:  The sample consisted of 102 cone beam computed tomography (CBCT) images for 62 male patients (mean age 29.92 ± 9.04 years) and 40 female patients (mean age 29.70 ± 9.54 years). Four distances and three densities were measured; a multivariate analysis of variance and Mann-Whitney's U test were applied to compare the differences between sexes., Results:  For the first maxillary molar, there were significant differences between males and females in terms of coronal width (13.95 ± 1.31 and 13.22 ± 1.159 mm, respectively) and middle width (14.28 ± 1.43 and 13.57 ± 1.478 mm, respectively). However, no significant difference was found regarding height (7.93 ± 3.8 mm for both) or apical width (14.68 ± 2 mm for both). Regarding the second maxillary molar, significant differences between males and females were found in terms of coronal width (14.66 ± 1.63 and 13.54 ± 1.512 mm, respectively), middle width (14.35 ± 1.825 and 13.25 ± 1.52 mm, respectively), and height (7.29 ± 3.00 and 8.66 ± 3.16 mm, respectively), whereas the gender dimorphism regarding apical width had borderline significance (14.09 ± 1.731 mm; p  = 0.048). No significant differences were found regarding density., Conclusion:  The minimum average alveolar bone height for the second maxillary molar region was 7.29 ± 30 mm with significant gender dimorphism. Therefore, CBCT scans should be recommended prior to immediate implant placement., Competing Interests: None declared., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).)

Introduction: This study aimed to evaluate the available retromolar space for ramal plates in patients with Class I and III malocclusions and compare that space with and without third molars using cone-beam computed tomography., Methods: Cone-beam computed tomography images of 30 patients (17 males, 13 females; mean age, 22.2 ± 4.5 years) with Class III malocclusion and 29 subjects (18 males, 11 females; mean age, 24.3 ± 3.7 years) with Class I malocclusion were analyzed. Available retromolar space at 4 axial levels of the second molar root and the volume of the retromolar bone were evaluated. Two-way repeated measures analysis of covariance (repeated measures analysis of covariance) was applied to compare the variables between Class I and III malocclusions and the presence of third molars., Results: Patients with Class I and III relationships showed up to 12.7 mm of available retromolar space at 2 mm apical from the cementoenamel junction (CEJ). At 8 mm apical from CEJ, patients with Class III malocclusion had 11.1 mm of space, whereas those with a Class I relationship showed 9.8 mm of available space. When patients had third molars, the amount of available retromolar space was significantly greater in patients with a Class I and III relationship. However, patients with Class III malocclusion exhibited greater available retromolar space than those with a Class I relationship (P = 0.028). In addition, the bone volume was significantly greater in patients with Class III malocclusion than in patients with a Class I relationship and those with third molars than in those without them (P <0.001)., Conclusions: Class I and III groups showed the availability of at least 10.0 mm of retromolar space 2 mm apical to the CEJ for molar distalization. Based on this information, it is suggested that clinicians consider available retromolar space for molar distalization in diagnosing and planning treatment for patients with Class I and III malocclusion., (Copyright © 2023 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The purpose of this study was to assess speech perturbation and adaptation for patients wearing modified C-palatal plates (MCPPs) over time., Methods: The sample consisted of 40 patients, 20 wearing MCPPs as the experimental group (age: 20.7 ± 5.8 years) and 20 patients wearing a transpalatal arch (TPA) as the control group (age: 21.5 ± 6.4 years). The sounds /t/, /d/, /s/, /n/, /r/, /tʃ/. and /j/ were recorded for each patient at six time points: immediately before (T0) and after (T1) appliance placement; then 1, 2, 3 and 4 weeks after placement (T2-T5). Acoustic analysis of pitch and voice onset time (VOT) was performed by Praat software. Repeated measures analysis of variance (RM-ANOVA) was used to assess changes in the pitch and VOT over time and the difference between the appliances., Results: With the MCPP appliance, /n/, /r/, /tʃ/ and /j/ decreased in VOT starting in the first week while /t/ and /s/ almost returned to pre-treatment levels after 2 weeks. VOT for the /d/ sound did not change between T0 and T3, but it decreased after 3 weeks. There were no significant differences in pitch and VOT between the two groups at any time point., Conclusions: Wearing an MCPP device caused patients to initially distort the articulation of several sounds, but the distortion dissipated within 1 to 2 weeks. It is recommended that patients and/or their parents be advised during pre-treatment counselling of the possibility of temporary speech changes with MCPP placement., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: The aim of this retrospective study was to introduce a novel technique of a double-scan protocol with markerfree registration and compare it to the already-used techniques regarding the accuracy of registration., Materials and Methods: Fifty-nine fully edentulous patients underwent double-scan procedures by three different methods: the barium sulfate method for 11 patients; the gutta-percha method for 26 patients; and the marker-free method for 22 patients. Point-to-point registration of the two scans was followed by a voxel-based surface "best fit" registration. The mean registration error of each case was digitally recorded. Differences in registration error between groups were evaluated using one-way analysis of variance (ANOVA)., Results: The accuracy of the registration showed no significant differences according to the method (P = .719)., Conclusion: The marker-free procedure was presented as a novel technique for registration of the scans in the double-scan protocol. There was no significant difference in the accuracy of the registration between the three techniques: marker-free, gutta-percha markers, and fully radiopaque barium sulfate scan appliance. Therefore, the marker-free technique might be a viable option for the double-scan protocol.

Introduction: This study aimed to compare the skeletodental and soft tissue changes with total arch distalization using a modified C-palatal plate (MCPP) and maxillary first premolar extraction treatment in Class II malocclusion patients with severe overjet., Setting and Sample Population: The sample consisted of 46 adult patients who had Class II Division 1 malocclusion with severe overjet; 25 of them received non-extraction treatment with MCPPs (age, 22.5 ± 7.2 years), and 21 received maxillary first premolar extraction treatment (age 23.4 ± 6.5 years)., Method: A total of 26 variables were measured on pre- and post-treatment lateral cephalograms. To evaluate the differences between pretreatment and post-treatment in each group, t tests and Wilcoxon rank-sum tests were used. To compare the amount of change between the two groups, MANOVA test was used., Results: The overjet was significantly reduced in the MCPP and extraction groups by 4.8 mm and 5.4 mm, respectively. However, the two groups had no significant difference in the sagittal, vertical and angular changes of the maxillary incisors. In addition, regarding soft tissue changes, the MCPP and extraction groups showed an increased nasolabial angle of 7.5° and 9.4°, decreased upper lip to the true vertical line of 1.8 mm and 2.2 mm, respectively (P < .001)., Conclusions: There was no significant difference in the skeletal changes between the MCPP and extraction groups, and the reduction in overjet was similar in the groups. These results suggest that MCPP might be a viable treatment option for total arch distalization in Class II malocclusion patients with severe overjet., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: This study aimed to compare the amount of tooth movement after multiple horizontal (MH) and single vertical (SV) micro-osteoperforations (MOPs), and evaluate the histological changes after orthodontic force application in rabbits., Methods: The mandibles of 24 white rabbits were subjected to two experimental interventions: MH and SV MOPs. Defect volume of the MOPs between the two groups was kept similar. A force of 100 cN was applied via a coil spring between the incisor teeth and the first premolars. The amount of tooth movement was measured. Differences in the amount of tooth movement and bone variables at three time points and between the two groups were evaluated using repeated-measures analysis of variance., Results: The first premolar showed a mesial movement of 1.47 mm in the MH group and 1.84 mm in the SV group, which was significantly different at Week 3 ( p < 0.05). No significant difference was observed in bone volume and bone fraction between the groups. Tartrate-resistant acidic phosphatase-positive cell count was also significantly greater at Week 3 than at Week 1 in both the SV and MH groups., Conclusions: The amount of tooth movement showed significant differences between Weeks 1 and 3 in the SV and MH MOP groups, but showed no differences between the two groups. Therefore, SV MOP could be considered an effective tool for enhancing tooth movement, especially for molar distalization, uprighting, and protraction to an edentulous area.

Objective: The aims of this study were (a) to evaluate the displacement and stress distribution in the maxillary dentition associated with the use of two different unilateral distalization appliances-unilateral zygoma gear (UZG) appliance and asymmetric headgear (AHG)-in non-growing patients; and (b) to assess the effects of fully erupted maxillary third molars on the distalization of the first molar with both appliances by using three-dimensional finite element analysis., Settings and Sample Population: Two 3D models of the maxilla were created: one with third molars and one without. Next, two distalizing appliances (UZG and AHG) were added to each model to create four models., Materials and Methods: Distalization forces were applied, and the resultant displacements were recorded at the mesiobuccal and distolingual cusps and palatal root apex of each molar and the incisal edge root apex of the central incisors. The resulting von Mises stress distributions were evaluated., Results: With the UZG, the first molar showed greater root distalization than the crown in the model with the third molar, whereas the model without the third molar showed distalization and distal tipping of the first molar. With the AHG, the first molar showed a large amount of distal tipping in the model without a third molar. However, this tipping was less than that in the model with third molars., Conclusion: The presence of completely erupted third molars decreased the amount of uncontrolled distal tipping in both appliances. UZG can be considered as an effective option for maxillary molar distalization., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: The aim of this systematic review is to assess the treatment effects (amount of distalization, distal tipping and vertical movement) of buccally versus palatally placed temporary skeletal anchorage devices (TSADs) on maxillary first molars during distalization., Materials and Methods: Medline and Scopus databases were searched up to September 2020 for randomized controlled trials (RCTs) and non-randomized prospective cohort studies on maxillary molar distalization using TSADs in patients with Class II malocclusion. After study selection, data extraction and risk of bias assessment, meta-analyses were performed for the amount of distalization, distal tipping and intrusion of first molars., Results: Nine studies (2 RCTs and 7 prospective studies) were included. The risk of bias of the RCTs was low to unclear. The non-randomized studies were of moderate quality. In five studies, the TSADs were placed in the infrazygomatic process while in two studies, they were placed in the buccal inter-radicular spaces, and in two studies, they were placed in the midpalatal region. The first molar distalization was 2.75 mm when buccal inter-radicular TSADs were used, but 4.07 and 4.17 mm with palatal and infrazgomatic TSADs. The palatal appliances were associated with 11.17° of distal tipping of the first molar while infrazygomatic and buccal inter-radicular TSADs resulted in 3.99° and 1.70° of tipping, respectively., Conclusions: Inter-radicular TSADs resulted in less distal tipping but also in less distalization. Palatal TSAD-supported appliances showed the greatest amount of distal tipping. Further RCTs or prospective studies on the effect of various designs of TSAD-supported distalization are warranted., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: The aim of this study was to compare the facial esthetic standards between Paraguayan and Korean beauty pageant contestants as well as to evaluate the deviation in Farkas proportion indexes (PI) from the golden ratio for each group using three-dimensional (3D) stereophotogrammetric analysis., Methods: 3D soft tissue images of 34 Miss Paraguay (MP) and 54 Miss Korea (MK) pageant contestants were obtained. The 3D images were digitized and 52 measurements and ratios were calculated. One-way multivariate analysis of variance was applied to compare the two groups. One-sample t-test was applied to assess the differences between the PI of each group and the golden ratio., Results: The MP group showed greater mouth width, total vermilion perimeter, and lower lip protrusion (P < 0.001) than the MK group. Meanwhile, the MK group showed longer forehead height and total facial height (P = 0.002 and P < 0.001, respectively). All Farkas PIs in each group showed significant differences from the golden ratio except for PI19 (upper/lower vermilion heights)., Conclusions: Paraguayans favor rectangular faces with wide mouths and large lips, especially the lower lips, whereas Koreans prefer long tapered faces with small mouths and lips. All proportion indexes were significantly different from the golden ratio except for PI19. Therefore, it would be beneficial for clinicians to consider the differences in ethnic preferences in facial esthetics during diagnosis and treatment planning., (Copyright © 2020 World Federation of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of study was to evaluate skeletodental and soft tissue treatment effects and the amount of maxillary molar distalization with modified C-palatal plates vs. Greenfield molar distalizer appliances in adolescents. Study design: The samples consisted of pre- and posttreatment lateral cephalograms collected from 39 patients with Class II malocclusion. The MCPP group was comprised of 21 patients (mean age: 11.7 ± 1.3 years) treated with MCPP appliances while the GMD group included 18 patients (mean age: 11.2 ± 0.9 years) treated with GMD. Fixed orthodontic treatment started with the distalization process in both groups. From each cephalograpm, twenty-nine variables were measured for analysis and then the two groups were compared. Descriptive statistics, a paired t-test, and multivariate analysis of variance were performed to compare the treatment effects within and between the groups. Results: There was significant treatmentrelated change in the sagittal position of the maxilla and the mandible within each group. However, there were no statistically significant inter-group differences. The mean maxillary first molar distalization was 3.96 mm in the MCPP group vs. 2.85 mm in the GMD group. Both groups showed minimal distal tipping, but the maxillary incisors were significantly extruded by 3.04 ± 0.89 mm (P < .001) in GMD group. There was no significant difference in treatment duration between the groups. Conclusions: The maxillary first molars of both the MCPP and GMD groups were effectively distalized and there were significant skeletal changes in the maxilla. However, the maxillary incisors were significantly extruded in the GMD group.

Introduction: The purpose of this study was to evaluate skeletal, dentoalveolar, and soft tissue changes at 3 years posttreatment in patients with Class II Division 1 malocclusion treated with modified C-palatal plates (MCPPs)., Methods: The sample consisted of 69 lateral cephalograms of 23 patients Class II Division 1 malocclusion (9 men, 14 women; average age, 20.1 years) who underwent bilateral distalization of their maxillary dentition. The lateral cephalograms were taken immediately before the placement of the MCPPs (T1); at the end of orthodontic fixed appliance therapy (T2); and at the posttreatment observation period (3 years posttreatment; T3). Twenty-three variables were measured. Repeated measures ANOVA followed by post hoc analysis using Bonferroni test was used to identify significant differences between time points., Results: Maxillary first molars showed a distal movement of 3.44 ± 1.08 mm (P <0.001) distal crown tipping of 2.35° ± 6.74°, and intrusion of 1.42 ± 1.12 mm from T1 to T2. However, from T2 to T3, there was an average of 0.41 ± 0.25 mm of mesial movement, 0.50 ± 0.46 mm of extrusion, and insignificant mesial crown tipping (0.92° ± 2.46°; P = 0.06). The nasolabial angle increased 9.36° ± 6.04° from T1 to T2 (P <0.001) but then decreased 1.55° ± 1.54° from T2 to T3., Conclusions: MCPPs are a viable treatment option for maxillary total arch distalization with minimal changes in treatment effects 3 years posttreatment., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: This study aimed to identify significant factors affecting the spontaneous angular changes of impacted mandibular third molars as a result of second molar protraction. Temporary skeletal anchorage devices in the missing mandibular first molar (ML-6) or missing deciduous mandibular second molar (ML-E) with missing succedaneous premolar spaces provided traction., Methods: Forty-one mandibular third molars of 34 patients (10 male and 24 female; mean age 18.3 ± 3.7 years) that erupted after second molar protraction were included in this study. They were classified into upright (U) and tilted (T) groups. Linear and angular measurements were performed at the time of treatment initiation (T1) and of ML-6 or ML-E space closure (T2). Regression analyses were used to identify significant factors related to third molar uprighting., Results: Nolla stage (odds ratio [OR] 4.1), sex (OR 0.003 for male), third molar angulation at T1 (OR 1.1), missing tooth space (OR 0.006), rate of third molar eruption (OR 23.3), and rate of second molar protraction (OR 0.2) significantly affected third molar uprighting. Age, third molar angulation at T1, rate of third molar eruption, and rate of second molar protraction were significant factors for predicting third molar angulation at T2., Conclusions: Available space for third molar eruption before and after second molar protraction is not associated with uprighting of erupting third molars. Older patients whose third molars are in greater Nolla stage, are in a more upright position at T1, and have a greater eruption rate have a greater chance for third molar uprighting. Alternatively, an increase in second molar protraction rate results in mesial tipping of the third molars., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the amount of tooth movement and histologic changes with different corticotomy designs and micro-osteoperforation in rabbits., Methods: The sample consisted of 24 rabbits divided into three experimental groups (triangular corticotomy [TC] and indentation corticotomy [IC] with flap, and flapless micro-osteoperforations [MP]) and a control. A traction force of 100 cN was applied by connecting the first premolars to the incisors. The amount of tooth movement was measured. Kruskal-Wallis test was used to assess differences in tooth movement between the groups. Micro-computed tomography, hematoxylin and eosin staining, and tartrate-resistant acidic phosphatase (TRAP) analysis were performed. Analysis of variance was applied to assess differences in TRAP-positive osteoclast count between the groups., Results: The amount of tooth movement increased by 46.5% and 32.0% in the IC and MP groups, respectively, while the bone fraction analysis showed 69.7% and 8.5% less mineralization compared to the control. There were no significant intergroup differences in the number of TRAP-positive osteoclasts., Conclusions: The micro-osteoperforation group showed no significant differences in the amount of tooth movement compared to the corticotomy groups, nor in the TRAP-positive osteoclast count compared to both corticotomy groups and control., Competing Interests: CONFLICTS OF INTEREST: No potential conflict of interest relevant to this article was reported.

Objective: The aim of this study was to evaluate the biomechanical effects of temporary skeletal anchorage devices (TSADs) on the mandibular dentition and mandible during total arch distalization according to locations and types of the TSADs using finite element (FE) analysis., Setting and Sample Population: A model of the mandible and teeth was used to build an FE analysis model., Materials and Methods: Four FE models were constructed: Ramal plate (Type A), Sugawara plate (Type B), buccal shelf miniscrew (Type C) and interradicular miniscrew (Type D). A retraction force of 300 g per side was applied to the mandibular archwire., Results: In the sagittal plane, the plates Type A and B showed more distal displacement than the miniscrew Types C and D, especially in the posterior teeth. Type A presented the greatest amount of distal displacement, followed by Types B, C and D. Type A was closest to the line of occlusion, which showed the lowest degree of buccolingual angulations of the molar crowns. Vertically, Type A showed a greater amount of extrusive displacement of the posterior teeth than the other types of TSADs, while Type B showed intrusive displacement of the molars., Conclusions: The ramal plate showed a greater amount of distal and extrusive displacement of the posterior teeth than the miniscrews. Therefore, clinicians should consider the displacement of mandibular dentition during total arch distalization according to types of the TSADs., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: Our objectives were to evaluate changes in the position of maxillary third molars with cone-beam computed tomography images in adolescents after total arch distalization using a modified C-palatal plate (MCPP) and to compare them with the changes in a matched control group., Methods: We included 68 maxillary third molars of 40 adolescent patients (mean age, 12.6 years). They were divided into MCPP and control groups. Cone-beam computed tomography images were taken before and after molar distalization (mean duration, 14.4 months) in the MCPP group and also in the control group (mean duration, 12.9 months). The changes in the position, angulation, and rotation of the third molars were assessed, and the volumes of maxillary tuberosity were measured., Results: After distalization, the third molars moved backward (1.2 mm) and upward (0.5 mm) in the MCPP group with a significant difference (P <0.003), and they moved downward and forward in the control group. The changes in rotation and angulation were insignificant. The volumes of maxillary tuberosity increased in both groups., Conclusions: Maxillary total arch distalization caused unerupted third molars to move backward and upward, with an insignificant difference in the posttreatment volume of maxillary tuberosity. Therefore, it may be possible to perform maxillary total arch distalization in adolescents with unerupted third molars without a germectomy, at least in the short term., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The purpose of this study was to analyze initial displacement and stress distribution of the maxillofacial complex during dentoskeletal maxillary protraction with various appliance designs placed on the palatal region by using three-dimensional finite element analysis., Methods: Six models of maxillary protraction were developed: conventional facemask (Type A), facemask with dentoskeletal hybrid anchorage (Type B), facemask with a palatal plate (Type C), intraoral traction using a Class III palatal plate (Type D), facemask with a palatal plate combined with rapid maxillary expansion (RME; Type E), and Class III palatal plate intraoral traction with RME (Type F). In Types A, B, C, and D, maxillary protraction alone was performed, whereas in Types E and F, transverse expansion was performed simultaneously with maxillary protraction., Results: Type C displayed the greatest amount of anterior dentoskeletal displacement in the sagittal plane. Types A and B resulted in similar amounts of anterior displacement of all the maxillofacial landmarks. Type D showed little movement, but Type E with expansion and the palatal plate displayed a larger range of movement of the maxillofacial landmarks in all directions., Conclusions: The palatal plate served as an effective skeletal anchor for use with the facemask in maxillary protraction. In contrast, the intraoral use of Class III palatal plates showed minimal skeletal and dental effects in maxillary protraction. In addition, palatal expansion with the protraction force showed minimal effect on the forward movement of the maxillary complex., Competing Interests: No potential conflict of interest relevant to this article was reported.

Objective: The purpose of this study was to compare the skeletal, dental, and soft-tissue treatment effects of nonextraction therapy using the modified C-palatal plate (MCPP) to those of premolar extraction (PE) treatment in adult patients with Class II malocclusion., Methods: Pretreatment and posttreatment lateral cephalographs of 40 adult patients with Class II malocclusion were retrospectively analyzed. The MCPP group comprised 20 patients treated with total arch distalization of the maxillary arch while the PE group comprised 20 patients treated with four PE. Fifty-eight linear and angular measurements were analyzed to assess the changes before and after treatment. Descriptive statistics, paired t -test, and multivariate analysis of variance were performed to evaluate the treatment effects within and between the two groups., Results: The MCPP group presented 3.4 mm of retraction, 1.0 mm of extrusion, and 7.3° lingual inclination of the maxillary central incisor. In comparison, the PE group displayed greater amount of maxillary central incisor retraction and retroclination, mandibular incisor retraction, and upper lip retraction (5.3 mm, 14.8°, 5.1 mm, and 2.0 mm, respectively; p < 0.001 for all). In addition, the MCPP group showed 4.0 mm of distalization and 1.3 mm of intrusion with 2.9° distal tipping of the maxillary first molars., Conclusions: These findings suggest the MCPP is an effective distalization appliance in the maxillary arch. The amount of incisor retraction, however, was significantly higher in the PE group. Therefore, four PE may be recommended when greater improvement of incisor position and soft-tissue profile is required., Competing Interests: CONFLICTS OF INTEREST: No potential conflict of interest relevant to this article was reported.

Objectives: To evaluate the changes in position of the maxillary dentition and the airway space after distalization using a modified C-palatal plate (MCPP) in adult patients through CBCT images and to analyze the relationship between the amount of distalization and the changes in the airway space., Materials and Methods: CBCT images of 33 adult Class II patients (22.2 ± 4.0 years old; 27 women and 6 men) treated by total maxillary arch distalization using the MCPP were evaluated before and after distalization. The patients were divided into nonextraction and extraction groups. The changes in the airway space as well as the changes in the positions of the maxillary dentition were evaluated. The distalization effects were calculated and assessed using paired t-tests., Results: After distalization, the first molar showed significant distalization and intrusion ( P < .001) with no significant rotation of the crown and no significant buccal displacement of its root in the transverse dimension. There were no significant changes in the airway volume or the minimum cross-sectional area of the oropharynx., Conclusions: The application of the MCPP resulted in significant total arch distalization without a significant effect on the transverse dimensions or changes in the oropharynx airway space. The MCPP can be considered a viable treatment option for patients with Class II malocclusion.

Objective: The purpose of this study was to compare the treatment effects of palatally vs buccally placed temporary anchorage devices., Materials and Methods: Of 40 Class II division 1 malocclusion patients, 22 were treated with modified C-palatal plate (MCPP) appliances (age 21.9 ± 6.6 years), and 18 (age 24.2 ± 6.8 years) were treated with buccally placed miniscrews between the maxillary first molar and second premolar. A total of 26 linear and angular measurements were analyzed on pre- and posttreatment lateral cephalograms. Multivariate analysis of variance was performed to evaluate the treatment effects within each group and to compare the effects between groups., Results: Overall, the MCPP appliances showed 4.2 mm of distalization, 1.6 mm of intrusion of the first molar with 2° tipping, and 0.8 mm extrusion of incisors. The miniscrew group resulted in 2.0 mm of distalization, 0.1 mm intrusion of the first molar with 7.2° tipping, and 0.3 mm of incisor extrusion. Regarding soft tissue change, in the MCPP group, the upper lip was significantly retracted ( P < .001)., Conclusions: Comparing the treatment effects between MCPP appliances and buccal miniscrews, the MCPP appliances showed greater distalization and intrusion with less distal tipping of the first molar and less extrusion of the incisor compared to the buccal miniscrews.

A modified C-palatal plate (MCPP) is introduced as a treatment option for adolescent patients with Class I malocclusion and severe overjet. A boy, 10 years 11 months old, was successfully treated without extractions in 22 months. Indications for clinical application of the MCPP as well as procedures and biomechanical analysis of the treatment effects are described in detail. The MCPP was used to distalize the maxillary dentition. The results were stable 1 year after retention. Clinicians should consider the application of MCPP as a nonextraction treatment option for adolescents with Class I malocclusion and severe overjet when the patient or parent refuses extractions., (Copyright © 2017 American Association of Orthodontists. All rights reserved.)

Objective: The purpose of this study was to evaluate the dental and skeletal effects of the modified C-palatal plate (MCPP) for total arch distalization in adult patients with Class II malocclusion and compare the findings with those of cervical pull headgear., Methods: The study sample consisted of the lateral cephalograms of 44 adult patients with Class II Division 1 malocclusion, including 22 who received treatment with MCPP (age, 24.7 ± 7.7 years) and 22 who received treatment with cervical pull headgear (age, 23.0 ± 7.7 years). Pre- (T1) and post-treatment (T2) cephalograms were analyzed for 24 linear and angular measurements. Multivariate analysis of variance was performed to evaluate the changes after treatment in each group and differences in treatment effects between the two groups., Results: The mean amount of distalization at the crown and root levels of the maxillary first molar and the amount of distal tipping was 4.2 mm, 3.5 mm, and 3.9° in the MCPP group, and 2.3 mm, 0.6 mm, and 8.6° in the headgear group, respectively. In addition, intrusion by 2.5 mm was observed in the MCPP group. In both groups, the distal movement of the upper lip and the increase in the nasolabial angle were statistically significant ( p < 0.001). However, none of the skeletal and soft tissue variables exhibited significant differences between the two groups., Conclusions: The results of this study suggest that MCPP is an effective treatment modality for total arch distalization in adults., Competing Interests: The authors report no commercial, proprietary, or financial interest in the products or companies described in this article.

Objective: The aims of this study were to measure and compare the facial dimensions of the Miss Korea pageant contestants and a selected group of women from the general population by using three-dimensional (3D) image analysis, as well as to compare various facial ratios to the golden ratio within each group., Methods: Three-dimensional images of 52 Miss Korea pageant contestants (MK group) and 41 young female adults selected from the general population (GP group) were acquired. Fifty-four variables and ratios were measured and calculated. Intergroup comparisons were performed using multivariate analysis of variance., Results: Compared to the GP group, the MK group showed greater total facial height and eye width, lesser lower-facial height, and lesser facial, lower-facial, and nasal widths. Moreover, compared to the GP group, the MK group had more protruded noses with greater nasolabial angle, greater vertical curvature of the foreheads, lesser horizontal curvature of the cheek, and lesser lower-lip-and-chin volume., Conclusions: The MK group had longer faces but smaller lower lips and chins than did the GP group. The golden ratio was not matching the current facial esthetic standards. These data might be beneficial for treatment planning of patients undergoing orthognathic and plastic surgeries., Competing Interests: The authors report no commercial, proprietary, or financial interest in the products or companies described in this article.

Introduction: The purpose of this study was to analyze displacement and stress distribution in the maxilla during maxillary expansion followed by protraction using bone-borne and conventional tooth-borne palatal expanders and a facemask via 3-dimensional finite element analysis., Methods: A finite element model of an adolescent skull was created, and 4 different types of appliances were integrated into it: facemask (type A); facemask with paramedian bone-borne expander (type B), facemask with palatal-slope bone-borne expander (type C), and facemask with conventional expander (type D). Expansion of 0.25 mm followed by 500 g of force per side was applied., Results: Type A showed anterior displacement of the dentition combined with downward displacement of posterior teeth and upward displacement of anterior teeth. The combination of protraction and expansion in type D showed the greatest anterior displacement. In types B and C, the expansion forces resulted in posterior displacement decreasing the net displacement of the combination. Stresses concentrated around the miniscrews in types B and C. In types A and D, stresses concentrated at the first premolar and first molar. Type B had the highest stresses followed by type C and then D., Conclusions: The conventional tooth-borne expander (type D) enhanced the effect of maxillary protraction. Facemask alone (type A) resulted in more anterior displacement of the maxilla than the combination of facemask and bone-borne expanders (types B and C). The clinician should be aware of the initial stresses and movements from different expanders with facemask found in this study and confirm the movements in future clinical Class III studies., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to evaluate the effects of segmental osteotomy on the blood vessels and osteoclasts in rats using micro-computed tomography (micro-CT) and histomorphometric analysis. After segmental osteotomy was performed around the maxillary first molars of 36 male Sprague-Dawley rats (n = 72), the samples were divided into a control group (no displacement), 0.5 D group (0.5 mm buccal displacement) and 1.0 D group (1.0 mm buccal displacement) (n = 24/group). At 1, 2, 4 and 8 weeks after surgery, changes in the blood vessel volume were investigated using micro-CT with perfusion of radiopaque silicone rubber. Tartrate-resistant acid phosphatase (TRAP) staining was used for histomorphometric analysis. Two-way repeated measures analysis of variance (rmANOVA) was performed to compare the volume of blood vessels and number of TRAP-positive osteoclasts among the groups. Regarding blood vessel volume, the displacement groups had no significant effects, while the time points had significant effects (p = 0.014). The blood vessel volume at 1 week was significantly smaller than that at 2, 4, and 8 weeks (p = 0.004, p = 0.026, and p = 0.005, respectively). Regarding TRAP cell count, the displacement groups had no significant effects, while the time points had significant effects (p < 0.001). The number of TRAP-positive osteoclasts at 8 weeks was significantly smaller than that at 1, 2, and 4 weeks (p < 0.001, p < 0.001, and p = 0.002, respectively), and the count at 4 weeks was smaller than that at 1 week (p = 0.011). Therefore, a regional osteoclast-related acceleratory phenomenon was maintained until 4 weeks after surgery.

Objective: This study aimed to (1) evaluate the effects of maxillary second and third molar eruption status on the distalization of first molars with a modified palatal anchorage plate (MPAP), and (2) compare the results to the outcomes of the use of a pendulum and that of a headgear using three-dimensional finite element analysis., Methods: Three eruption stages were established: an erupting second molar at the cervical one-third of the first molar root (Stage 1), a fully erupted second molar (Stage 2), and an erupting third molar at the cervical one-third of the second molar root (Stage 3). Retraction forces were applied via three anchorage appliance models: an MPAP with bracket and archwire, a bone-anchored pendulum appliance, and cervical-pull headgear., Results: An MPAP showed greater root movement of the first molar than crown movement, and this was more noticeable in Stages 2 and 3. With the other devices, the first molar showed distal tipping. Transversely, the first molar had mesial-out rotation with headgear and mesial-in rotation with the other devices. Vertically, the first molar was intruded with an MPAP, and extruded with the other appliances., Conclusions: The second molar eruption stage had an effect on molar distalization, but the third molar follicle had no effect. The application of an MPAP may be an effective treatment option for maxillary molar distalization., Competing Interests: The authors report no commercial, proprietary, or financial interest in the products or companies described in this article.

The retromolar fossa is an anatomically suitable skeletal anchorage site. The aim of this report was to introduce a novel appliance for the correction of skeletal Class III malocclusions with mandibular dentition distalization. The placement site and the procedure of the ramal plate are described. The resulting force vectors are parallel to the functional occlusal plane leading to efficient molar distalization. This approach is demonstrated with 2 adult patients who refused a surgical treatment option. This ramal plate may be indicated for total arch distalization for nonextraction and nonsurgical cases., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate (1) whether vertical eruption of impacted third molars improves after mesialization of second molars and (2) what factors affect the vertical eruption of impacted third molars when space caused by missing molars is successfully closed by mesialization of the second molar using miniscrews., Materials and Methods: The treatment group (Group 1) included 52 patients who had (1) missing mandibular first molars (ML-6) or missing deciduous mandibular second molars (ML-E), (2) initially impacted mandibular third molars, and (3) successful space closure of the edentulous area with orthodontics. Panoramic radiographs at start of treatment (T1) and at time of space closure (T2) were collected. The control group (Group 2) included 46 nonedentulous patients with impacted mandibular third molars without molar protraction treatment. Panoramic radiographs with similar T1/T2 treatment times were selected. Nine measurements were obtained regarding horizontal available space, vertical eruption, and third molar angulation., Results: Third molars erupted vertically an average of 2.54 mm in Group 1 compared with 0.41 mm in Group 2. Age, gender, Nolla stage, and angle of the third molars did not show significant correlations with the vertical change of the impacted third molars, whereas the depth of third molar impaction and available space showed significant correlations., Conclusions: Impacted mandibular third molars vertically erupt as a result of uprighting with mesialization of the second molar, and vertical eruption is affected by the initial vertical location of impacted third molars and available space.

Objective: The purpose of this study was to evaluate treatment effects after distalization of the mandibular dentition using ramal plates through lateral cephalograms., Methods: Pre- and post-treatment lateral cephalograms and dental casts of 22 adult patients (11 males and 11 females; mean age, 23.9 ± 5.52 years) who received ramal plates for mandibular molar distalization were analyzed. The treatment effects and amount of distalization of the mandibular molars were calculated and tested for statistical significance. The significance level was set at p < 0.001., Results: The mandibular first molar distalization at the crown and root were 2.10 mm (p < 0.001) and 0.81 mm (p = 0.011), respectively. In the evaluation of skeletal variables, there was a significant increase in the Wits appraisal (p < 0.001). In the evaluation of the soft tissue, there was no significant effect on upper lip position, but the lower lips showed a significant retraction of 2.2 mm (p < 0.001)., Conclusions: The mandibular molars showed a significant amount of distalization accompanied by limited extrusion and mesiobuccal rotation of the crowns. A ramal plate may be a viable device for mandibular total arch distalization in Class III patients who are reluctant to undergo orthognathic surgery.

Purpose: The purpose of this study was to evaluate the stability of bilateral sagittal split ramus osteotomy (BSSO) setback with rigid internal fixation in a surgery-first approach (SFA) for patients with skeletal Class III malocclusion., Patients and Methods: Twenty-seven consecutive patients with skeletal Class III malocclusion treated with BSSO with the SFA were included in the study. Lateral cephalograms were taken and traced before surgery and 1 and 6 months after surgery. Cephalometric measurements were compared using repeated-measures analysis of variance. A P value less than or equal to .05 was considered significant., Results: The study included 9 men (age, 25.7 ± 2.9 yr) and 18 women (age, 26.6 ± 4.2 yr). Treatment time was 8.4 ± 1.5 months. Horizontally, there were no meaningful anteroposterior changes of the pogonion and B point during the postsurgical period (0.9 and 0.6 mm, respectively). Vertically, the pogonion showed superior movement after surgery (2.4 mm) without major postsurgical change (0.6 mm). The B point showed major superior movement after surgery (2.3 mm) and during the postsurgical period (1.2 mm). The inclination of the lower incisor was increased labially during the postsurgical period (2.4°), although this was not statistically important., Conclusions: In the present study, there was no major horizontal relapse for any variable (<1 mm). Vertically, all variables showed no meaningful changes during the postsurgical period except the B point showed 1.2 mm of superior displacement. BSSO with rigid fixation using the SFA seems to be an effective and predictable procedure in patients with skeletal Class III malocclusion., (Copyright © 2016. Published by Elsevier Inc.)

The palate has been reported to be a suitable skeletal anchorage site in adolescents and adults. This article introduces new treatment modalities for correction of sagittal discrepancies by molar protraction and distalization with a modified palatal anchorage plate appliance. The effectiveness and versatility of this method are demonstrated in 2 adolescent patients., (Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the facial dimensions of young adult women with a preferred facial appearance and compare the results with those from the general population., Methods: Twenty-five linear, nine angular, and three area measurements were made and four ratios were calculated using a sample of standardized frontal and lateral photographs of 46 young adult women with a preferred facial appearance (Miss Korea group) and 44 young adult women from the general population (control group). Differences between the two groups were analyzed using multivariate analysis of variance (MANOVA)., Results: Compared with the control group, the Miss Korea group exhibited a significantly greater facial height, total facial height (TFH; trichion-menton), facial width (tragus right-tragus left), facial depth (tragus-true vertical line), and trichion-nasion/TFH ratio and smaller subnasale-menton/TFH and facial width/TFH ratios. Furthermore, the control group had smaller intercanthal and interpupillary widths., Conclusions: The Miss Korea group exhibited longer, wider, and deeper faces compared with those from the general population. Furthermore, the Miss Korea group had larger eyes, longer but less protruded noses, longer and more retruded lower lips and chins, larger lip vermilion areas, and smaller labiomental angles. These results suggest that the latest trends in facial esthetics should be considered during diagnosis and treatment planning for young women with dentofacial abnormalities.

Correction of a severe protrusive soft tissue profile without orthognathic surgery can be challenging. This case report describes the treatment of a young woman with a severe bimaxillary protrusion. Orthodontic treatment included extraction of her 4 first premolars and total arch distalization of both arches using a palatal plate appliance. The total treatment time was 24 months. Her occlusion and facial appearance were significantly improved., (Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate and compare skeletal effects and the amount of molar distalization in maxilla using modified palatal anchorage plate (MPAP) vs headgear appliances in adolescent patients., Materials and Methods: Pre- and posttreatment lateral cephalograms of 45 Class II malocclusion patients were analyzed; 24 were treated with MPAP appliances (age, 12.4 years) and 21 with headgear (age, 12.1 years). Fixed orthodontic treatment started with the distalization process in both groups. Thirty-two variables were measured and compared between both groups using multivariate analysis of covariates., Results: There was no significant main effect of the appliance type on the treatment results (P  =  .063). Also, there was no significant main effect of the appliance type on both pre- and posttreatment comparisons (P  =  .0198 and .135, respectively). The MPAP and headgear groups showed significant distalization of maxillary first molars (3.06 ± 0.54 mm and 1.8 ± 0.58 mm, respectively; P < .001). Sagittal skeletal maxillomandibular differences were improved after treatment (P < .001), with no significant differences between the two groups. No significant difference in treatment duration was found between the groups., Conclusions: The MPAP showed a significant skeletal effect on the maxilla. Both MPAP and headgear resulted in distalization of maxillary first molars. Therefore, it is recommended that clinicians consider the application of MPAP, especially in noncompliant Class II patients.

Maxillary protraction is the conventional treatment for growing Class III patients with maxillary deficiency, but it has undesirable dental effects. The purpose of this report is to introduce an alternative modality of maxillary protraction in patients with dentoskeletal Class III malocclusion using a modified C-palatal plate connected with elastics to a face mask. This method improved skeletal measurements, corrected overjet, and slightly improved the profile. The patients may require definitive treatment in adolescence or adulthood. The modified C-palatal plate enables nonsurgical maxillary advancement with maximal skeletal effects and minimal dental side effects.

Objectives: The aim of this study was to analyse the displacement and stress distribution in the maxillofacial complex during maxillary protraction with buccal and palatal plates using three-dimensional finite element analysis., Materials and Methods: Three anchorage appliance models-palatal plate (Type A), miniplate at the infrazygomatic crest (Type B), and conventional tooth-borne appliance (Type C)-were designed and integrated into a skull model. Protraction force was 500 g per side and force direction was forward and 30 degree downward to the maxillary occlusal plane. The stress distribution around the circum-maxillary sutures and the displacement of the surface landmarks were analysed., Results: All models showed forward and upward displacement at anterior nasal spine, Point A, and prosthion and forward and downward displacement at posterior nasal spine resulting in a counter-clockwise rotation. This anterior displacement was greatest in Type A. At the maxillary process of the zygoma, upward movement was shown only in Type A, whereas downward movement was observed in Types B and C. The greatest stresses in Type A were at the pterygomaxillary and the zygomaticotemporal sutures. Type B showed the greatest stress at the frontomaxillary suture., Limitations: Type A showed asymmetric results; however, it was not of clinical significance., Conclusion: The palatal plate resulted in wider stress distribution and more forward displacement compared to miniplate at the infrazygomatic crest area and conventional tooth-borne appliances. It might be recommended to consider the application of the palatal plate for maxillary protraction in Class III patients., (© The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: The purposes of this study were 1) to classify lingual dental arch form types based on the lingual bracket points and 2) to provide a new lingual arch form template based on this classification for clinical application through the analysis of three-dimensional virtual models of normal occlusion sample., Methods: Maxillary and mandibular casts of 115 young adults with normal occlusion were scanned in their occluded positions and lingual bracket points were digitized on the virtual models by using Rapidform 2006 software. Sixty-eight cases (dataset 1) were used in K-means cluster analysis to classify arch forms with intercanine, interpremolar and intermolar widths and width/depth ratios as determinants. The best-fit curves of the mean arch forms were generated. The remaining cases (dataset 2) were mapped into the obtained clusters and a multivariate test was performed to assess the differences between the clusters., Results: Four-cluster classification demonstrated maximum intercluster distance. Wide, narrow, tapering, and ovoid types were described according to the intercanine and intermolar widths and their best-fit curves were depicted. No significant differences in arch depths existed among the clusters. Strong to moderate correlations were found between maxillary and mandibular arch widths., Conclusions: Lingual arch forms have been classified into 4 types based on their anterior and posterior dimensions. A template of the 4 arch forms has been depicted. Three-dimensional analysis of the lingual bracket points provides more accurate identification of arch form and, consequently, archwire selection.

The purpose of this study was to investigate the three-dimensional (3D) morphologic differences in the mandibular arch of Vietnamese and North American White subjects. The sample included 113 Vietnamese subjects (41 Class I, 37 Class II and 35 Class III) and 96 White subjects (29 Class I, 30 Class II and 37 Class III). The samples were regrouped according to arch form types (tapered, ovoid, and square) to compare the frequency distribution of the three arch forms between ethnic groups in each angle classification. The facial axis point of each tooth was digitized on 3D virtual models. Four linear and two ratio variables were measured. In comparing arch dimensions, the intercanine and intermolar widths were wider in Vietnamese than in Whites (p < 0.001, p = 0.042, respectively). In the White group, there was even frequency distribution of the three arch forms. However, in the Vietnamese group, the square arch form was the most frequent followed by tapered and ovoid arch forms. The arch forms of Whites were narrower than Vietnamese. In North American Whites, the distribution of the arch form types showed similar frequency. In Vietnamese, the square arch form was more frequent.

The aim of this study was to analyze stress distribution and displacement of the maxilla and teeth according to different designs of bone-borne palatal expanders using micro-implants. A three-dimensional (3D) finite-element (FE) model of the craniofacial bones and maxillary teeth was obtained. Four designs of rapid maxillary expanders: one with micro-implants placed lateral to mid-palatal suture (type 1), the second at the palatal slope (type 2), the third as in type 1 with additional conventional Hyrax arms (type 3), and the fourth surgically assisted tooth-borne expander (type 4) were added to the FE models. Expanders were activated transversely for 0.25mm. Geometric nonlinear theory was applied to evaluate Von-Mises Stress distribution and displacement. All types exhibited downward displacement and demonstrated more horizontal movement in the posterior area. Type 3 showed the most transverse displacement. The rotational movement of dentoalveolar unit was larger in types 1 and 3, whereas it was relatively parallel in types 2 and 4. The stresses were concentrated around the micro-implants in types 1 and 3 only. Type 2 had the least stress concentrations around the anchorage and showed alveolar expansion without buccal inclination. It is recommended to apply temporary anchorage devices to the palatal slopes to support expanders for efficient treatment of maxillary transverse deficiency., (© The Author 2012. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Introduction: The purpose of this study was to evaluate the treatment effects of maxillary posterior tooth distalization performed by a modified palatal anchorage plate appliance with cephalograms derived from cone-beam computed tomography., Methods: The sample consisted of 40 lateral cephalograms obtained from the cone-beam computed tomography images of 20 Class II patients (7 men, 13 women; average age, 22.9 years) who underwent bilateral distalization of their maxillary dentition. The lateral cephalograms were derived from the cone-beam computed tomography images taken immediately before placement of a modified palatal anchorage plate appliance and at the end of distalization. Paired t tests were used for comparisons of the changes., Results: The distal movement of the maxillary first molar was 3.3 ± 1.8 mm, with distal tipping of 3.4° ± 5.8° and intrusion of 1.8 ± 1.4 mm. Moreover, the maxillary incisors moved 3.0 ± 2.7 mm lingually, with lingual tipping of 6.2° ± 7.6° and insignificant extrusion (1.1 mm; P = 0.06). The occlusal plane angle was increased significantly (P = 0.0001)., Conclusions: The maxillary first molar was distalized by 3.3 mm at the crown and 2.2 mm at root levels, with distal tipping of 3.4°. It is recommended that clinicians should consider using the modified palatal anchorage plate appliance in treatment planning for patients who require maxillary total arch distalization., (Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Purpose: The purposes of the present study were to evaluate the effects of frequent applications of low-level laser therapy (LLLT) on corticotomy-assisted tooth movement in a beagle dog model and to compare the effects in the mandible and maxilla., Materials and Methods: In 4 male beagles, the maxillary and mandibular second premolars were extracted. The third premolars were corticotomized and then protracted from the canines with a continuous force of 200 g. Daily LLLT (using an aluminum gallium indium phosphide [AlGaInP] diode) was applied at the buccal mucosa of the corticotomized premolars on 1 side only. The tooth movement was measured for 8 weeks. Fluorochromes were injected intravenously at the start of the experiment (T0) and after 2 (T2), 4 (T4), and 8 (T8) weeks to evaluate new bone formation on the tension sides. Histomorphometric and immunohistologic evaluations were performed., Results: In the mandible, the movement of the corticotomized premolars in the LLLT plus corticotomy group was less than that in the corticotomy-only group, although the difference was not statistically significant. In the maxilla, no significant differences between the 2 groups were found. Osteoclastic and proliferating cell activities and the amount of new bone formation were greater in the mandibular LLLT plus corticotomy group than in the corticotomy-only group., Conclusions: The frequent application of LLLT showed no significant effect on the corticotomized tooth movement., (Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Introduction: The aim of this study was to analyze stress distribution and displacement of the craniofacial structures resulting from bone-borne rapid maxillary expanders with and without surgical assistance using finite element analysis., Methods: Five designs of rapid maxillary expanders were made: a tooth-borne hyrax expander (type A); a bone-borne expander (type B); and 3 bone-borne surgically assisted modalities: separation of the midpalatal suture (type C), added separation of the pterygomaxillary sutures (type D), and added LeFort I corticotomy (type E). The geometric nonlinear theory was applied to evaluate the Von Mises stress distribution and displacement., Results: The surgical types C, D, and E demonstrated more transverse movement than did the nonsurgical types A and B. The amounts of expansion were greater in the posterior teeth in types A and B, but in types C, D, and E, the amounts of expansion were greater in the anterior teeth. At the midpalatal suture, the nonsurgical types showed more anterior expansion than did the posterior region, and higher stresses than with the surgical types. Type B showed the highest stresses at the infraorbital margin, anterior and posterior nasal spines, maxillary tuberosity, and pterygoid plate and hamulus., Conclusions: The 3 surgical models showed similar amounts of stress and displacement along the teeth, midpalatal sutures, and craniofacial sutures. Therefore, when using a bone-borne rapid maxillary expander in an adult, it is recommended to assist it with midpalatal suture separation, which requires minimal surgical intervention., (Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: To determine Korean facial profile preferences based on lip position as assessed by Hispanic-Americans of varying western adaptation levels and to determine whether the age and sex of the rater had any influence., Methods: For this study, 132 Hispanic-Americans and 68 Caucasians of varying age, sex and western adaptation levels volunteered to rate their preference of Korean male and female facial silhouettes having lips ranging from retruding to protruding. The Hispanic-Americans were also asked to complete a Bidimensional Acculturation Scale questionnaire to determine their western adaptation status: low-acculturated Hispanics (LAH; lesser western-adapted Hispanic participants) or high-acculturated Hispanics (HAH; higher western-adapted Hispanic participants)., Results: The LAHs preferred significantly more retruded lip positions (p < 0.05) while HAHs showed some similarities with Caucasian participants in the results for the Korean male profile, even though HAHs preferred more retruded lip positions for the Korean female profile than Caucasians did (p < 0.05). The age and sex of raters did not influence the preference of facial profiles (p > 0.05)., Conclusions: The results of this study suggest that Hispanic-Americans prefer a flatter Korean lip profile. It would be prudent for orthodontists to offer patients the option of altering lip profile through orthodontic and/or orthognathic surgery treatments.