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Objective: To systematically review studies on canine agenesis prevalence in different populations and continents, based on the jaw, sex, location, and associated dental anomalies., Methods: Electronic and hand searches of English literature in PubMed, Web of Science, Scopus, OpenGrey, and Science Direct were conducted, and the authors were contacted when necessary. Observational studies (population-based, hospital/clinic-based, and cross-sectional) were included. For study appraisal and synthesis, duplicate selection was performed independently by two reviewers. Study quality was assessed using a modified Strengthening the Reporting of Observational Studies in Epidemiology checklist, with main outcome of prevalence of canine agenesis., Results: The global population prevalence of canine agenesis was 0.30% (0.0-4.7%), highest in Asia (0.54%), followed by Africa (0.33%), and the least in Europe and South America (0.19% in both continents). Canine agenesis was more common in the maxilla (88.57%), followed by both maxilla and mandible (8.57%), and the least common was mandible-only presentation (2.86%). The condition was more common in females (female:male ratio = 1.23), except in Asia (female:male ratio = 0.88) and Africa (female:male ratio = 1). In Asia, unilateral agenesis was almost twice as prevalent as bilateral, but in Europe, the bilateral form was more common., Conclusions: The overall prevalence of canine agenesis is 0.30%, with the highest prevalence in Asia, followed by Africa, Europe, and South America. The condition is more common in the maxilla than the mandible, and in females than males (except in Asia and Africa), with unilateral agenesis being more common in Asia and the bilateral form showing a greater prevalence in Europe.

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.)

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: The aim of this finite element study was to analyze and clarify the mechanics of tooth movement patterns for total distalization of the mandibular dentition based on force angulation., Methods: Long-term orthodontic movement of the mandibular dentition was simulated by accumulating the initial displacement of teeth produced by elastic deformation of the periodontal ligament., Results: Displacement of each tooth was caused by movement of the whole dentition, elastic deflection of the archwire, and clearance gap between the archwire and bracket slot. The whole dentition was rotated clockwise or counterclockwise when the line of action of the force passed below or above the center of resistance. Elastic deflection of the archwire induced a lingual tipping of the anterior teeth. It became larger when increasing the magnitude of angulation. The archwire could be rotated within the clearance gap between the archwire and the bracket slot, and thereby the teeth tipped., Conclusions: Mechanics of total mandibular distalization was clarified. Selective use of force angulation with a careful biomechanical understanding can achieve proper distalization of the whole mandibular dentition., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

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.)

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.)

A 22-year-old woman came with a unilateral missing mandibular first molar and buccal crossbite. The open space was closed by protraction of the mandibular left second molar and uprighting and protraction of the horizontally impacted third molar using temporary skeletal anchorage devices, and her buccal crossbite was corrected with modified palatal and lingual appliances. The total active treatment time was 36 months. Posttreatment records after 9 months showed excellent results with a stable occlusion., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

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 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.)

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.)

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.)

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.)

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.)

Objective: To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction., Methods: Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with pre-adjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed., Results: Both groups showed full retraction of the maxillary anterior teeth by controlled tipping and space closure without altered posterior occlusion. However, the preformed C-wire group had a shorter retraction period (by 3.2 months). Furthermore, the maxillary molars in this group showed no significant mesialization, mesial tipping, or extrusion; some mesialization and mesial tipping occurred in the conventional C-wire group., Conclusions: Preformed C-wires combined with maxillary TSADs enable simultaneous leveling and space closure from the beginning of the treatment without maxillary posterior bonding. This allows for faster treatment of dentoalveolar protrusion without unwanted side effects, when compared with conventional C-wire, evidencing its clinical expediency.

The purposes of this study were to mechanically evaluate distalization modalities through the application of skeletal anchorage using finite element analysis. Base models were constructed from commercial teeth models. A finite element model was created and three treatment modalities were modified to make 10 models. Modalities 1 and 2 placed mini-implants in the buccal side, and modality 3 placed a plate on the palatal side. Distalization with the palatal plate in modality 3 showed bodily molar movement and insignificant displacement of the incisors. Placing mini-implants on the buccal side in modalities 1 and 2 caused the first molar to be distally tipped and extruded, while the incisors were labially flared and intruded. Distalization with the palatal plate rather than mini-implants on the buccal side provided bodily molar movement without tipping or extrusion. It is recommended to use our findings as a clinical guide for the application of skeletal anchorage devices for molar distalization., (© The Author 2011. 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.)

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 analyze the effect of low-level laser therapy (LLLT) on perception of pain after separator placement and compare it with perceptions of control and placebo groups using a frequent irradiation protocol., Materials and Methods: Eighty-eight patients were randomly allocated to a laser group, a light-emitting diode (LED) placebo group, or a control group. Elastomeric separators were placed on the first molars. In the laser and LED groups, first molars were irradiated for 30 seconds every 12 hours for 1 week using a portable device. Pain was marked on a visual analog scale at predetermined intervals. Repeated measure analysis of variance was performed for statistical analysis., Results: The pain scores of the laser group were significantly lower than those of the control group up to 1 day. The pain scores in the LED group were not significantly different from those of the laser group during the first 6 hours. After that point, the pain scores of the LED group were not significantly different from those of the control., Conclusions: Frequent LLLT decreased the perception of pain to a nonsignificant level throughout the week after separator placement, compared with pain perception in the placebo and control groups. Therefore, LLLT might be an effective method of reducing orthodontic pain.

Unlabelled: OBIECTIVES: 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., Methods: The facial axis (FA) and root centre (RC) points of mandibular teeth were identified on 32 CBCT images. FA and WALA points were digitised on 3D models of 28 mandibular casts from the same sample. The relationships between dental and basal arch dimensions, and between the two basal depth dimensions derived from RC and WALA points were statistically assessed by Pearson's correlation., Results: Strong correlations were found between dental and basal intercanine and intermolar arch widths. Also, the basal intercanine width showed a moderate correlation with dental intermolar width and depth. The basal intercanine and intermolar widths measured on 3D models showed moderate correlations with those measurements on CBCT, whereas the basal canine and molar depths showed no correlations., Conclusions: The dental and basal anterior and posterior arch widths were strongly correlated in normal occlusion. No correlations were found between the arch depths measured from WALA points and RC points. Hence, RC points may represent more useable landmarks compared to WALA points in the evaluation of basal arch forms. It is recommended that the relationship between the dental and basal arches is evaluated during treatment planning in order to improve arch co-ordination.

Introduction: The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensions in subjects with asymmetric skeletal Class III malocclusion and those with normal occlusion., Methods: Cone-beam computed tomography scans of 38 subjects with normal occlusion and 28 patients with facial asymmetry were evaluated and digitized with Invivo software (Anatomage, San Jose, Calif). Three midsagittal and 13 right and left measurements were taken. The paired t test was used to compare the right and left sides in each group. The Mann-Whitney U test was used to compare the midsagittal variables and the differences between the 2 sides of the group with normal occlusion with those of asymmetry patients., Results: The posterior part of the mandibular body showed significant differences between the deviated and nondeviated sides in asymmetric Class III patients. The difference of the asymmetry group was significantly greater than that of the normal occlusion group for the mediolateral ramal and the anteroposterior condylar inclinations (P = 0.007 and P = 0.019, respectively)., Conclusions: The asymmetric skeletal Class III group showed significant differences in condylar height, ramus height, and posterior part of the mandibular body compared with the subjects with normal occlusion. These results might be useful for diagnosis and treatment planning of asymmetric Class III patients., (Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Introduction: The purpose of this study was to compare the bone thickness of the palatal areas in early and late mixed and early permanent dentitions according to dental age., Methods: Cone-beam computed tomography scans of 118 subjects were selected and divided into 38 early mixed (8.03 ± 0.93 years), 40 late mixed (11.51 ± 0.92 years), and 40 permanent (20.92 ± 1.17 years) dentition subjects. The measurements of palatal bone thickness were made at 49 sites by using InVivoDental5.0 software (Anatomage, San Jose, Calif). Repeated measures analysis of variance was used to analyze intragroup and intergroup differences as well as sex dimorphism., Results: There was significantly lower bone thickness in the early mixed dentition group than in the 2 other groups (P <0.001). Bone thickness was higher in the anterior region than in the middle and posterior regions (P <0.001). Also, significant differences were found among the midline, medial, and lateral areas of the palate., Conclusions: Palatal bone thicknesses were significantly lower in the early mixed dentition group than in both the late mixed and permanent dentition groups. These findings might be helpful for clinicians to enhance the successful use of temporary anchorage devices in the palate., (Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

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., Methods: One hundred and twenty five plaster models of Class I occlusions were 3-D scanned (Orapix Co., Ltd, Seoul, Korea) and FA points digitized on the virtual models using Rapidform 2006 software (INUS Technology Inc., Seoul, Korea). Following intercanine and intermolar arch width and depth measurements, K-means cluster analysis was applied on 77 cases (Dataset 1) to classify the sample into arch form types. A curve of best fit of the mean arch form of each type was generated. The remaining 48 cases (Dataset 2) were mapped into the clusters and a multivariate test was performed to assess the differences among the clusters., Results: Classification into five clusters demonstrated maximum inter-cluster distance in the arch parameters and produced the most homogeneous cluster size. The differences between the 5 cluster types were statistically but not clinically significant and so they were recombined to form three clusters representing 'narrow', 'moderate' and 'wide' arch forms., Conclusions: A template with three arch form types based on anterior and posterior dimensions has been proposed through 3-D analysis of FA points for more accurate arch form identification and arch wire selection.

Aim: To evaluate changes of the lower facial portion on the frontal view before and after orthodontic treatment combined with anterior segmental osteotomy (ASO) in patients with bimaxillary protrusion., Methods: The sample consisted of 16 women in the experimental group who had received ASO and 24 women in the untreated control group. Twelve linear measurements, 5 angular measurements, and the lip perimeter and area were measured and analyzed using unpaired and paired t tests., Results: The upper lip height and lower lip to chin length were significantly greater after treatment. The upper and lower vermilion heights and all vermilion areas decreased significantly, while lip width did not change. Upper lip height was significantly greater in the posttreatment group than in the control group, but there was no difference in upper and total lip areas., Conclusion: Treatment combined with ASO significantly improved the frontal soft tissue proportions. Anticipated frontal soft tissue changes of the lower face should be considered by clinicians for accurate diagnosis and treatment planning.

Aim: To compare the differences in frontal esthetics in the lower face among Caucasian models, Korean models, and Korean nonmodels., Methods: The sample consisted of three groups comprising 36 Caucasian models, 30 Korean models, and 26 Korean nonmodels. Their frontal photos were scanned, and 12 distances, five angles, lip perimeter, and lip area were measured. Differences among groups were compared using one-way analysis of variance (ANOVA) and Tukey's test., Results: There was no significant difference in the upper lip height among the three groups. The Korean models had shorter lower lip to chin height than the two other groups. Full lip width was wider in the Korean and Caucasian models than in the Korean nonmodels. The Caucasian models had greater total vermilion area compared to both Korean groups. Finally, the Korean models had fuller lower and thinner upper vermilion areas than the nonmodels., Conclusions: Attractive lower facial portions in Caucasians are different from those of Koreans. Therefore, clinicians in Korea should use these data as guidelines for evaluating and enhancing patients' frontal facial esthetics., (© 2009 Quintessence Publishing Co, Inc. All Rights Reserved)

Objectives: Correction of dental origin asymmetry with conventional orthodontic mechanics is at risk of developing side effects because of the inherent asymmetric nature of tooth-borne anchorage-based asymmetric mechanics. Recently, the concept of skeletal anchorage using mini-implants has been introduced in the field of orthodontics and have shown successful results. The aim of this study is to demonstrate the clinical application of osseointegration of surface treated two component mini-implants (C-implant) in managing dental midline correction., Materials and Methods: The characteristics and procedure of asymmetric retraction for treating maximum anchorage using C-implant is shown with case reports of treated patients. The biomechanics and comparison to conventional mini-implant assisted midline correction methods are also described., Results: The authors show the clinical application of the mini implant dependent retraction technique during anterior retraction on various cases, possible indications, and simplicity of use., Conclusion: This article describes effective and simple methods of correcting dental asymmetry with mini-implants and its advantages will be discussed.

Aim: To show the clinical application of surface-treated mini-implants (C-Implants) in managing an anterior torque control during en masse retraction of anterior dentition., Methods: Nickel-titanium archwire with reverse curve of Spee, which is directly engaged in the hole of C-Implants, and severe curve of Spee can be overlaid on anterior segmented archwires to generate anterior torque on the anterior dentition to resist lingual tipping during en masse retraction. This treatment mechanics is called the biocreative therapy type II technique. The characteristics and procedure of the type II technique for treating maximum anchorage using the C-Implants is shown with case reports of treated patients. The biomechanics and a comparison to the type I technique of this treatment are also described., Results: The authors show the clinical application of type II technique during anterior retraction on various cases, possible indications, and simplicity of the mechanics., Conclusion: Biocreative therapy, which implements partial-osseointegrated mini-implants, presents a novel therapeutic approach in orthodontics. A technique of intrusion overlay archwires for anterior torque control also simplifies the design of orthodontic appliances while eliminating unwanted side effects, such as vertical changes on posterior anchorage teeth during en masse retraction.

A miniplate with tube (C-tube) was placed in the interdental spaces between both left and right upper second premolars and first molars in a 15-year-8 month-old male patient with a Class II malocclusion who with severe anterior protrusion and lower anterior crowding. The treatment plan consisted of extracting both upper first premolars, en masse retraction of the upper six anterior teeth and lower anterior decrowding. C-tubes were used as substitutes for posterior dental anchorage during upper anterior retraction. The particular design of the C-tubes made it possible to retract fully with minimal gingival irritation. The correct overbite and overjet were obtained by intruding and retracting the maxillary incisors to their proper positions and this correction remained stable for at least 27 months after debonding. Also, facial balance was improved. The active treatment period was 14 months. The application of this new appliance, consideration of case selection, and sequence of treatment are presented.