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We investigated the compensatory trends of mesiodistal angulation of first molars in malocclusion cases. We compared differences in the angulation of first molars in different developmental stages, malocclusion classifications and skeletal patterns. The medical records and lateral cephalogrammes of 1403 malocclusion cases taken before treatment were measured to evaluate compensation of molar angulation in relation to the skeletal jaw. The cases were stratified by age, Angle classification and skeletal patterns. Differences in the mesiodistal angulation of the first molars were compared among the stratifications. We observed three main phenomena. First, angulation of the upper first molar varied significantly with age and tipped most distally in cases aged <12 years and least distally in cases aged >16 years. The lower first molar did not show such differences. Second, in Angle Class II or skeletal Class II cases, the upper first molar was the most distally tipped, the lower first molar was the most mesially tipped, and opposite angulation compensation was observed in Class III cases. Third, in high-angle cases, the upper and lower first molars were the most distally tipped, and opposite angulation compensation was observed in low-angle cases. These data suggest that the angulation of the molars compensated for various growth patterns and malocclusion types. Hence, awareness of molar angulation compensation would help to adjust occlusal relationships, control anchorage and increase the chances of long-term stability.

Introduction: In this study, we compared patterns of morphologic variations of the craniofacial skeleton between patients affected by clefts who were operated on and unaffected subjects, aiming to discuss possible morpho-functional consequences of treatment in craniofacial development., Methods: The lateral cephalograms of 76 subjects, comprising patients with operated unilateral cleft lip and palate (OpC) and a group matched for sex and age without cleft, were used. Thirteen landmarks were used as variables in geometric morphometric tests quantifying and describing overall shape variation, differences between group means, allometry, and upper-lower face covariation., Results: The OpC group showed broader shape variations including noncleft group characteristics, but mainly a retrognathic maxilla, a vertically elongated face, a more open mandibular angle, and a more closed basicranial angle. Group means differed mainly in the maxillomandibular relationships. Allometry differed between groups, with the smallest OpC patients showing the most altered morphology. Upper and lower face covariation was stronger in the OpC group, showing mainly vertical changes in the anterior face., Conclusions: Operated patients affected by clefts achieve a broad range of morphologies; the most altered were found in those with skeletal Class III and small size. Furthermore, their strongest upper and lower face shape covariation suggests that a harmonic dental occlusion could be a key factor in achieving "normal" craniofacial morphology., (Copyright © 2014 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: All parts of the face, other than jaw relationships, should be considered in orthodontic treatment planning. The role of forehead and neck in facial esthetics is well known; however, the majority of conventional facial analysis methods have not considered them. Neck and forehead may confer mutual effects on equilibrium and on esthetics of other facial components, and may change the overall convexity/concavity view of the profile. Therefore, the aim of this study was to assess the effect of anteroposterior position of the forehead and neck on the esthetics of skeletal class I, II and III jaw relationships using profile silhouettes., Methods: Class II and III jaw relationships were constructed on the silhouette of a class I normal profile by altering the mandibular position. Retruded, normal and protruded positions were also applied for the forehead and neck. Three hundred Iranian laypeople (150 men, 150 women) scored the esthetics of profile silhouettes from 1 to 7. Half of the participants were told to consider the profiles as a man, and the other half were told to consider them as a woman. Data were analyzed using non-parametric methods., Results: Class I jaw relation was found to be the most beautiful profile followed by class II and III respectively. Esthetics of different positions of the neck and forehead were significantly different (P < 0.05). In subjects with a normal neck and forehead position, and those with a retruded neck, the best esthetic relationship was class I, and the worst was class III. For protruded foreheads, the best jaw relationship was class II for females and class I for males, and the worst was class III for both. In a retruded forehead position, the most preferred jaw relationship was class I, and the worst was class II. For profiles with a protruded neck, the best esthetics was found to be in class III jaw relationship, and the worst was in class II. There was a small difference in scoring for male and female profiles (P < 0.05); there were also small differences in scoring trends of men and women (P < 0.05)., Conclusion: This study showed that the anteroposterior position of the forehead and neck affects the esthetics of jaw relationships in profile view. In laypeople's opinions, in a normal profile, the overall appearance is more important compared to the independent position of the neck and forehead; however, having jaw abnormalities, the neck plays an important independent role. The preferred jaw relation for profiles with each forehead or neck position was introduced.

Background/objective: Facial asymmetry is very common in adult class III patients; however, the degree of facial asymmetry in growing class III subjects has been poorly investigated. Therefore, the aim was to assess the degree of facial asymmetry of growing class III subjects and to compare it with a sample of growing subjects without malocclusion, recorded using a three-dimensional laser scanning method and classified according to the dentition phase., Subjects/methods: A group of 156 Caucasian subjects, 52 with class III malocclusion (28 females and 24 males) and 104 without malocclusion (control, 51 females and 53 males), with an overall mean age 6.7±1.4 years (range 4.3-10.3 years), were included. The subjects were further subdivided according to the presence of either primary or early/intermediate mixed dentitions. Facial asymmetry was assessed on three-dimensional surface facial images obtained using a laser scanning device in terms of mirrored face distances and percentages of asymmetry. Multivariate analyses were used to assess the differences among class III and control groups., Results: Complete facial symmetry was not seen in any subject. No significant differences of facial asymmetry were observed between the class III and control groups, neither in the primary nor in the early/intermediate mixed dentition phases., Limitations: No conclusions about longitudinal changes in the degree of facial asymmetry among class III subjects could be drawn from the present cross-sectional study., Conclusions: Based on three-dimensional facial asymmetry analysis, class III subjects do not show clinically relevant facial asymmetry, at least during the pre-pubertal growth period., (© The Author 2013. 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 objectives of this study were to clarify the characteristics of cranial-base morphology in adults with skeletal Class III malocclusion and investigate factors relating to the establishment of a skeletal Class III malocclusion., Methods: Initial lateral cephalograms of women were examined. Subjects with an ANB angle of 0° to 4°, normal overjet and overbite, and a Class I molar relationship were classified as Class I (n = 86). Those with an ANB angle less than -1°, a Wits appraisal less than 2 mm, a negative overjet, and a Class III molar relationship were the Class III group (n = 86) in this study. Angular, linear, and coordinate measurements were made. Multivariate analysis of variance and the Student t test were used to analyze significant differences between the 2 groups. Discriminant analysis, logistic regression analysis, and decision analysis were used to identify which cranial-base and maxillomandibular variables influenced the establishment of a skeletal Class III malocclusion., Results: The Class III group had smaller values for NSBa, SeSBa, FH-SSe, and FH-SBa. Sphenoidale and basion were more inferior and anterior than those of the Class I group. There was no difference in the anterior and posterior cranial-base lengths between the groups. Greater mandibular length was the first major characteristic in the Class III group, followed by smaller values for SeSBa and NSBa., Conclusions: Cranial-base morphology in adults with a skeletal Class III malocclusion is different from that in a skeletal Class I malocclusion. Smaller cranial-base angles, steeper posterior cranial bases, more inferiorly positioned sphenoidale, and more anteriorly positioned basion are major characteristics of skeletal Class III malocclusions. These characteristics play important roles in the establishment of a skeletal Class III malocclusion., (Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the effects of different surgical procedures on soft tissue and skeletal changes., Patients and Methods: Pre- and postoperative lateral cephalograms of 191 class III patients aged 16-58 years were retrospectively analyzed and divided into three groups according to the surgical therapy they had undergone. Group I had undergone maxillary advancement (n=51), group II a bimaxillary (n=102) procedure, and group III mandibular setback (n=38). Cephalometric assessments were made at the beginning of orthodontic treatment (T1) and at least 8 weeks after surgical correction of the class III malocclusion (T2). Nasolabial angle and the distance between the lower lip and the esthetic line were evaluated as soft-tissue parameters, while the skeletal parameters included the SNA and SNB angles, Wits value, gonial angle, and relative position of the maxilla to mandible. Mean values and standard deviations were calculated and any significant difference between soft and hard tissue in association with surgery methods was determined applying the Wilcoxon test using SAS statistical software., Results: Compared to mandible setback, the number of bimaxillary procedures and maxilla advancements has increased significantly in recent years (0.04). SNA values measured at T2 were an average of 84° in group I, 83° in group II, and 82° in group III, thus, revealing a tendency to return to the normal range. SNB values measured at T2 averaged 81° in group I, 80° in group II, and 81° in group III. We observed significant changes in the nasolabial angle according to the surgical approach taken (p=0.018). Changes in the distance between the lower lip and the esthetic line were only slightly significant (p=0.050). No significant differences were noted among the surgical approaches in terms of SNA and SNB angles., Conclusion: The two groups that underwent advancement of the maxilla (groups I and II) revealed marked improvements in soft-tissue esthetics.

Many difficulties may arise during the finishing phase of orthodontic treatment on account of discrepancy between mandibular and maxillary tooth size. In 1958, Bolton devised the index that bears his name and enables possible tooth-size discrepancy to be diagnosed. Use of this index in practice has shown that it can vary depending on the different angle malocclusion classes. The aim of this work is to study variations of the Bolton index as a function of the malocclusion class in the Moroccan population, and to compare the results obtained with those of other populations. Ninety models were therefore selected in different groups of dental Class I, Class II and Class III malocclusions. The mesiodistal (MD) diameters of 12 maxillary and mandibular teeth were measured and the anterior and general Bolton indices were calculated. The results obtained show that there is no significant difference between the various groups of angle malocclusion classes, and that some other populations present results similar to those of the Moroccan sample., (Copyright © 2014 CEO. Published by Elsevier Masson SAS. All rights reserved.)

Background/aim: The literature suggests different views on the correlation between the cranial base morphology and size and saggital intermaxillary relationships. The aim of this study was to investigate the cranial base morphology, including the frontal facial part in patients with mandibular prognathism, to clarify a certain ambiguities, in opposing viewspoints in the literature., Methods: Cephalometric radiographies of 60 patients were analyzed at the Dental Clinic of the Military Medical Academy, Belgrade, Serbia. All the patients were male, aged 18-35 years, with no previous orthodontic treatment. On the basis of dental and sceletal relations of jaws and teeth, the patients were divided into two groups: the group P (patients with mandibular prognathism) and the group E (the control group or eugnathic patients). A total of 15 cephalometric parametres related to the cranial base, frontal part of the face and sagittal intermaxillary relationships were measured and analyzed., Results: The results show that cranial base dimensions and the angle do not play a significant role in the development of mandibular prognathism. Interrelationship analysis indicated a statistically significant negative correlation between the cranial base angle (NSAr) and the angles of maxillary (SNA) and mandibular (SNB) prognathism, as well as a positive correlation between the angle of inclination of the ramus to the cranial base (GoArNS) and the angle of sagittal intermaxillary relationships (ANB). Sella turcica dimensions, its width and depth, as well as the nasal bone length were significantly increased in the patients with mandibular prognathism, while the other analyzed frontal part dimensions of the face were not changed by the malocclusion in comparison with the eugnathic patients., Conclusion: This study shows that the impact of the cranial base and the frontal part of the face on the development of profile in patients with mandibular prognathism is much smaller, but certainly more complex, so that morphogenetic tests of the maxillomandibular complex should be included in further assessment of this impact.

Objective: To compare mean anterior (AR) and mean overall (OR) tooth size ratios, prevalence of clinically significant tooth size discrepancies (TSDs) and correlation between AR and OR in subjects with Class II division 1 and Class III malocclusion treated by surgical-orthodontic or orthodontic means., Design: Retrospective, cross-sectional., Setting: State-funded and private clinics., Participants: From pre-treatment cohorts of 770 surgical and 610 non-surgical subjects, Class II division 1 and Class III malocclusion groups were identified with 60 surgical and 60 non-surgical subjects, comprising 30 males and 30 females, in each., Methods: AR and OR were calculated by landmarking digital models. Differences in AR and OR and their relationship were analysed using two-way analysis of variance (ANOVA) and a correlation coefficient, respectively. The proportions of the surgical and non-surgical groups with a TSD were assessed using logistic regression. Intra-examiner reproducibility involved re-landmarking 30 randomly selected image sets and differences in ARs and ORs were compared using a paired t-test. Random error was assessed using the intraclass correlation coefficient (ICC). Analyses were performed using SAS (SAS Institute Inc., Cary, NC, USA) at the 5% level of significance., Results: There were no statistically significant differences associated with the measurement of either the mean AR (P = 0·913) or the mean OR (P = 0·874). ICC values were very high (AR = 0·95; OR = 0·90). Differences existed between both Class II and Class III surgical (AR: P<0·001; OR: P<0·001) and non-surgical groups (AR: P = 0·012; OR: P = 0·003). The AR and OR relationship was strong (correlation coefficient = 0·72). The highest percentage of clinically significant TSDs was seen in the AR of both Class II and Class III surgical groups (23·3%)., Conclusions: In the cohort examined: AR and OR differed significantly for malocclusion groups. The prevalence of clinically significant TSDs did not differ significantly between surgical and non-surgical groups although the highest percentage of clinically significant TSDs was recorded for AR in Class II and Class III surgical cases. AR and OR were closely related., (© 2014 British Orthodontic Society.)

The aim of this study was to evaluate facial morphology in 25 Class III and 46 non-Class III children aged 5-6 years using three-dimensional (3D) laser imaging; 3D facial images were obtained, two average facial templates were constructed for the non-Class III male and female groups, each individual face was superimposed on the corresponding average template and group comparisons were evaluated (facial height, facial convexity, mandibular position and facial surface morphology). Differences between parameters were evaluated by using an analysis of variance and colour deviation maps. The results showed that Class III children had less mid-face prominence and a concave facial profile when compared to non-Class III children (P = 0.002 and P = 0.018). The position of the pg point in the z-axis just failed to reach statistical significance when comparing the two groups (P = 0.051). A vertical analysis showed no statistical significance between the groups, when evaluating middle (n-sn) and lower (sn-pg) facial height. Coincidence of the Class III faces to normal templates with a tolerance set as 0.5 mm was low (less than 30%). The soft tissue characteristics of a Class III face differ significantly from the non-Class III face in the mid-face region and in the facial profile. A 3D laser imaging method evaluated and identified morphological characteristics of Class III children in deciduous dentition, which could in the future become an important diagnostic tool in small children. The most important clinical advantage of this study is the non-invasiveness of the method.

There have been numerous studies of facial esthetics, but few have benefited from the new techniques provided by 3D imaging. The aim of this study is to determine which are the most crucial cephalometric criteria for facial esthetics by identifying the strongest correlations between the esthetic rating and 3D Cephalometric values, the Cepha 3Dt. A group of 91 subjects (from 10 to 60 years of age) was rated by a jury of 50 randomly selected judges (from 12 to 65 years of age) using an analog scale. We then looked for the most important correlations between the esthetic ratings and the tridimensional cephalometric values by using 3D Cephalometric Analysis on a global sample, and on Class II and Class III sub-samples. Facial esthetics therefore appeared to be especially linked to: anterior-posterior dimension, maxillo-mandibular disharmony, relationships between the anterior areas (alveolar and basal), the alveolar region has a greater impact than the basal area on facial architecture. In the Class II group, sagittal discrepancies and mandibular divergence have an equal impact on the assessment of facial esthetics., (© EDP Sciences, SFODF, 2014.)

Objective: To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions., Materials and Methods: Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient., Results: Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r  =  0.83 and between Id-Me and LAFH it was r  =  0.81., Conclusions: The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.

Aim: The aim of this cephalometric study was to evaluate the influence of the sagittal skeletal pattern on the 'Y-axis of growth' measurement in patients with different malocclusions., Materials and Methods: Lateral head films from 59 patients (mean age 16y 7m, ranging from 11 to 25 years) were selected after a subjective analysis of 1630 cases. Sample was grouped as follows: Group 1 - class I facial pattern; group 2 - class II facial pattern; and Group 3 - class III facial pattern. Two angular measurements, SNGoGn and SNGn, were taken in order to determine skeletal vertical facial pattern. A logistic regression with errors distributed according to a binomial distribution was used to test the influence of the sagittal relationship (Class I, II, III facial patterns) on vertical diagnostic measurement congruence (SNGoGn and SNGn)., Results: RESULTS show that the probability of congruence between the patterns SNGn and SNGoGn was relatively high (70%) for group 1, but for groups II (46%) and III (37%) this congruence was relatively low., Conclusion: The use of SNGn appears to be inappropriate to determine the vertical facial skeletal pattern of patients, due to Gn point shifting throughout sagittal discrepancies. Clinical Significance: Facial pattern determined by SNGn must be considered carefully, especially when severe sagittal discrepancies are present.

Introduction: This study was designed to investigate dentoalveolar compensation in untreated skeletal Class III patients with either positive or negative overjet., Methods: The positive overjet groups consisted of 104 adults, divided into group 1 (angle between sella-nasion to mandibular plane (SN-MP) > 38°, n = 30), group 2 (30° < SN-MP < 38°, n = 43), and group 3 (SN-MP <30°, n = 31). The negative overjet groups (groups 4-6) consisted of 90 adults who were closely matched to the positive overjet groups with regard to the ANB and SN-MP angles. Twenty-two cephalometric measurements were compared between the matched groups. In the positive overjet groups, correlation analysis was performed between the skeletal and dental measurements, and regression analysis was performed to determine the incisor-mandibular plane angle., Results: The maxillary incisors were more proclined and the occlusal plane was more flattened in the positive overjet groups than in the negative overjet groups; however, there was no statistically significant difference between them with regard to mandibular incisor inclination. The inclinations of the maxillary and mandibular incisors were correlated with both the sagittal and vertical skeletal measurements. Eight regression equations for the incisor-mandibular plane angle were calculated with the highest coefficient of determination of 0.547., Conclusions: Proclination of the maxillary incisors and flattening of the occlusal plane contributed to a positive overjet. Mandibular incisor inclination was more closely associated with sagittal and vertical skeletal discrepancies and was not affected by the incisal relationship., (Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: To establish a method to prefabricate titanium plate with three-dimensional (3-D) printing technique for correction of mandibular prognathism in sagittal splint ramous osteotomy (SSRO)., Methods: Between January 2012 and May 2013, 12 patients with mandibular prognathism (Angle III malocclusion) were treated. Among them, 9 cases were male and 3 cases were female. Their ages ranged from 19 to 35 years (mean, 25.6 years). With the 3-D facial CT data of these patients, 3-D printer was used to print the models for preoperational simulation. SSRO was performed on 3-D models, and the titanium plates were prefabricated on the models after the distal segments were moved backward and rotated according to occlusal splint. During operations, the proximal segments were fixed to distal segments by the prefabricated titanium plates. 3-D CT scans were taken to examine the temporomandibular joint position changes before operation and at 6 months after operation., Results: The skull models were manufactured by 3-D printing technique, and the titanium plates were reshaped on the basis of them. Twenty-four prefabricated titanium plates were placed during operations, and they all matched with the bone segments well. Evaluation of 3-D CT scans showed that the temporomandibular joint position had no change. All patients were followed up 7-12 months (mean, 10.6 months). The face type and dental articulation were improved greatly. All cases obtained satisfactory opening function and occlusion., Conclusion: With the titanium plate fabricated based on 3-D models, surgeons are able to improve or refine surgical planning so that the operation can be performed according to preoperative simulation precisely and the complications, such as dislocation of temporomandibular joint, can be prevented.

Introduction: The aim of this research was to compare maxillary and mandibular molar heights and incisor inclinations in patients with skeletal open-bite Class II, patients with skeletal open-bite Class III, and an untreated control group., Methods: Pretreatment lateral cephalograms of 70 orthodontic patients (34 men, 36 women) between 16 and 40 years of age were examined. The sample was divided into 3 groups according to facial growth pattern and overbite. The control group (n = 25) included normodivergent Class I subjects with adequate overbite; the skeletal open-bite Class II group (n = 25) and the skeletal open-bite Class III group (n = 20) included hyperdivergent Class II or Class III subjects with negative overbite. Measurements considered were ANB angle, palatal and mandibular plane angles, maxillary incisor palatal plane angulation, and mandibular incisor mandibular plane angulation, as well as the distance from the palatal or the mandibular plane to the mesial cusp of the molars. Multivariate analysis of covariance and multivariate analysis of variance tests were used to determine the differences between the groups, followed by the Tukey post-hoc test. Additionally, the Mann-Whitney U test and Kruskall-Wallis test were performed., Results: Significant differences in molar height were found (P <0.001). A 4-mm difference in maxillary molar height between the skeletal open-bite and control groups was found. Mandibular molar height was greater in the skeletal open-bite Class II group (P <0.001). Maxillary incisor palatal plane angulation was greater in the skeletal open-bite Class III group by approximately 6°. Mandibular incisor to mandibular plane angulation was 10° more lingual in the skeletal open-bite Class III group (P <0.001)., Conclusions: The skeletal open-bite groups had greater molar heights than did the control group. The skeletal open-bite Class II group had more eruption of the mandibular molars. The maxillary incisors were more proclined and the mandibular incisors were more lingual in the skeletal open-bite Class III group., (Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: To investigate the association between maxillofacial morphology and mandibular bone volume in patients with skeletal malocclusion., Materials and Methods: Subjects were 118 adult Japanese (58 males and 60 females). Skeletal malocclusion was classified, based on cephalometric analysis, into skeletal Classes I (-1° ≤ ANB < 4°), II (ANB ≥ 4°), and III (ANB < -1°). Using cone-beam computed tomography and three-dimensional image analysis software, the dental crowns and mandible were separated, with only the mandible extracted. This was then reconstructed as a three-dimensional model, from which the mandibular volume was measured., Results: No significant difference in mandibular volume was noted among skeletal Classes I, II, and III, nor was there any significant correlation between mandibular volume and the ANB, SNB, or mandibular plane angles. There was occasional and limited correlation between mandible volume and gonial angle and certain cephalometric distance parameters., Conclusion: We conclude that proper understanding of the three-dimensional maxillofacial morphology requires not only cephalometric radiographic tracings but also high-resolution analysis of the mandibular area, width, and volume.

Objectives: The aim of this study was to compare the soft tissue changes influenced by reverse headgear therapy with (RHg + RME) or without (RHg) rapid maxillary expansion with each other and with an untreated Class III control group (C)., Study Design: RHg group (10 girls, 6 boys, mean chronological age 11.1 years), RHg + RME group (12 girls, 4 boys, mean chronological age 10.8 years) and C group (7 girls, 11 boys, mean chronological age 10.2 years) comprised skeletally Class III patients with maxillary deficiency Soft tissue measurements were made on lateral cephalograms at the beginning and at the end of the treatment and observation periods. Changes within each group and the differences between the groups were analyzed by paired t-test; the differences between the groups were determined by variance analysis and Duncan test with a significance level p < 0.05., Results: The sagittal depth of nose and maxilla, upper lip height and protrusion were significantly increased in treatment groups and the differences were significant when compared to control group (p < 0.05)., Conclusion: Forward movement of upper lip was more prominent in RHg group. Reverse headgear treatment with or without RME revealed significant soft tissue changes when compared with a growing Class III control group with the same skeletal characteristics.

Objectives: To investigate variability in the upper airway of subjects with different anteroposterior skeletal patterns by evaluating the volume and the most constricted cross-sectional area of the pharyngeal airway and defining correlations between the different variables., Material and Methods: The study sample consisted of 60 patients (29 boys, 31 girls) divided into three groups: Class I (1 ≤ ANB ≤ 3), Class II (ANB>3), and Class III (ANB<1), to evaluate how the jaw relationship affects the airway volume and the most constricted cross-sectional area (Min-CSA). Differences between groups were determined using the Tukey-Kramer test. Correlations between variables were tested using Pearson's correlation coefficient., Results: The volume and the Min-CSA of the pharyngeal airway (PA) were significantly related to anteroposterior skeletal patterns (p < 0.05). The nasopharyngeal airway (NA) volume of Class I and Class III subjects was significantly larger than that of Class II subjects (p < 0.05). The Min-CSA and the length of PA were significantly related to the volume of PA (p < 0.05). The site and the size of the Min-CSA varied among the three groups., Conclusions: The volume and the most constricted cross-sectional area of the airway varied with different anteroposterior skeletal patterns. The NA volume of Class I and Class III subjects was significantly larger than that of patients with a Class II skeletal pattern., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: The aim of this study was to assess the dentoskeletal effects of Class II malocclusion treatment performed with the Twin Block appliance., Methods: The experimental group comprised 20 individuals with initial mean age of 11.76 years and treated for a period of 1.13 years. The control group comprised 25 individuals with initial mean age of 11.39 years and a follow-up period of 1.07 years. Lateral cephalograms were taken at treatment onset and completion to assess treatment outcomes. Intergroup comparison was performed by means of the chi-square and independent t tests., Results: The Twin Block appliance did not show significant effects on the maxillary component. The mandibular component showed a statistically significant increase in the effective mandibular length (Co-Gn) and significant improvement in the maxillomandibular relationship. The maxillary and mandibular dentoalveolar components presented a significant inclination of anterior teeth in both arches. The maxillary incisors were lingually tipped and retruded, while the mandibular incisors were labially tipped and protruded., Conclusions: The Twin Block appliance has great effectiveness for correction of skeletal Class II malocclusion in individuals with growth potential. Most changes are of dentoalveolar nature with a large component of tooth inclination associated with a significant skeletal effect on the mandible.

OBJECTIVE. Upper airway changes caused by orthognathic surgery operations have been a topic of a concern in the orthodontic literature because of a possible development of obstructive sleep apnea. Diverse response of the airway patency could be expected if the dimensions of the airway differ among various malocclusions already before orthognathic treatment. However the associations between facial morphology and the upper airway dimensions have not been clarified. The purpose of this systematic review was to elucidate whether the upper airway dimensions differ among various sagittal craniofacial patterns. MATERIAL AND METHODS. MEDLINE and the Cochrane Library were searched up to November 2012. Reference lists of relevant articles were checked for further possible studies. Strict inclusion and exclusion criteria were applied when considering the studies to be included. Screening of eligible studies and data extraction were conducted independently by two reviewers. RESULTS. 758 studies were identified and 11 of these were recognized as suitable for further analysis. 75% of studies did not find differences in the nasopharyngeal dimensions among craniofacial patterns. The findings for the oropharyngeal dimensions were controversial as 5 of 11 investigations found these to be smaller in Class II subjects, and 6 of 11 concluded that oropharynx size is larger in Class III pattern. The vertical growth type of the subjects was not considered in five investigations, and 45% of the included studies used lateral cephalometry as only tool for airway assessment. CONCLUSIONS. Currently there is insufficient evidence that the upper airway dimensions differ in various sagittal skeletal patterns.

Objectives: (1) To evaluate the applicability of using 3D digital models in the assessment of the magnitude of occlusal contacts by measuring occlusal contact surface areas (OCSAs) and 3D mesh points in 'contact' (OCMPs) in a sample of orthodontic patients; (2) To detect any sex differences in the magnitude of occlusal contacts in all malocclusion groups; (3) To detect inter- group differences; (4) To assess possible correlations between occlusal contacts and other dental characteristics., Materials and Methods: Study casts of 120 malocclusion patients were selected and divided into 4 groups (class I division 1, class II division 1, class II division 2, class III) with equal numbers for both sexes. 3D digital models were produced using O3DM™ technology. Occlusal contacts were quantified using two methods of measuring., Results: (1) No significant sexual differences were detected for OCMPs (mesh points) and OCSAs (mm(2)) in all groups. (2) There were statistically significant differences among malocclusion groups for OCMPs and OCSAs (p < 0.001). Tukey's HSD post- hoc tests showed that class III patients had significantly less occlusal contacts than other malocclusion groups. (3) Stepwise multiple regression equations showed that overjet, lower arch width and overbite could explain approximately 19.5% of the total variance of OCSAs and OCMPs., Conclusion: Sexual differences in occlusal contacts were not detected. Class I division 1 patients had the highest amount of occlusal contacts among all groups of malocclusion. Overjet, overbite and lower dental arch width were best predictors of occlusal contacts in the current sample.

Objectives: To identify the timing of significant arch dimensional increases during orthodontic alignment involving round and rectangular nickel-titanium (NiTi) wires and rectangular stainless steel (SS). A secondary aim was to compare the timing of changes occurring with conventional and self-ligating fixed appliance systems., Methods: In this non-primary publication, additional data from a multicenter randomised trial initially involving 96 patients, aged 16 years and above, were analysed. The main pre-specified outcome measures were the magnitude and timing of maxillary intercanine, interpremolar, and intermolar dimensions. Each participant underwent alignment with a standard Damon (Ormco, Orange, CA) wire sequence for a minimum of 34 weeks. Blinding of clinicians and patients was not possible; however, outcome assessors and data analysts were kept blind to the appliance type during data analysis., Results: Complete data were obtained from 71 subjects. Significant arch dimensional changes were observed relatively early in treatment. In particular, changes in maxillary inter-first and second premolar dimensions occurred after alignment with an 0.014in. NiTi wire (P<0.05). No statistical differences in transverse dimensions were found between rectangular NiTi and working SS wires for each transverse dimension (P>0.05). Bracket type had no significant effect on the timing of the transverse dimensional changes., Conclusions: Arch dimensional changes were found to occur relatively early in treatment, irrespective of the appliance type. Nickel-titanium wires may have a more profound effect on transverse dimensions than previously believed., Clinical Significance: On the basis of this research orthodontic expansion may occur relatively early in treatment. Nickel-titanium wires may have a more profound effect on transverse dimensions than previously believed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: The role of ankyloglossia in etiology of malocclusion is not much discussed over the years. The aim of the present study was to assess the skeletal and dental characteristics in subjects with ankyloglossia., Methods: Fifty-seven subjects diagnosed with ankyloglossia (group 1) were compared with 60 subjects (group 2) without ankyloglossia, who had class I skeletal base. Ankyloglossia was diagnosed and graded (mild, moderate, severe and very severe) using Kortlow's method. SNA, SNB, ANB, Go-Gn-SN angle, FMA, maxillary and mandibular intercanine widths and intermolar widths, tooth size-arch length discrepancy in maxillary and mandibular arches and overbite were measured. Independent t test was used to compare the mean parameters between the two groups. Analysis of variance and Tukey honestly significant difference were used to compare mean parameters among various grades of ankyloglossia., Results: Majority of group 1 subjects belonged to class I skeletal base followed by class II and class III skeletal bases. Moderate ankyloglossia was most common in group 1. The mean maxillary and mandibular intercanine widths and maxillary intermolar width were statistically significant in independent t test (P<0.01) and reduced in group 1. In ANOVA followed by Tukey HS, the Go-Gn-SN angle and overbite were statistically significant among different grades of ankyloglossia (P<0.05)., Conclusions: Subjects with ankyloglossia had reduced maxillary and mandibular intercanine widths and reduced maxillary intermolar width. The mandibular plane angle and overbite were altered with severity of ankyloglossia.

Objective: To compare lower incisor dentoalveolar compensation and mandible symphysis morphology among Class I and Class III malocclusion patients with different facial vertical skeletal patterns., Materials and Methods: Lower incisor extrusion and inclination, as well as buccal (LA) and lingual (LP) cortex depth, and mandibular symphysis height (LH) were measured in 107 lateral cephalometric x-rays of adult patients without prior orthodontic treatment. In addition, malocclusion type (Class I or III) and facial vertical skeletal pattern were considered. Through a principal component analysis (PCA) related variables were reduced. Simple regression equation and multivariate analyses of variance were also used., Results: Incisor mandibular plane angle (P < .001) and extrusion (P  =  .03) values showed significant differences between the sagittal malocclusion groups. Variations in the mandibular plane have a negative correlation with LA (Class I P  =  .03 and Class III P  =  .01) and a positive correlation with LH (Class I P  =  .01 and Class III P  =  .02) in both groups. Within the Class III group, there was a negative correlation between the mandibular plane and LP (P  =  .02). PCA showed that the tendency toward a long face causes the symphysis to elongate and narrow. In Class III, alveolar narrowing is also found in normal faces., Conclusions: Vertical facial pattern is a significant factor in mandibular symphysis alveolar morphology and lower incisor positioning, both for Class I and Class III patients. Short-faced Class III patients have a widened alveolar bone. However, for long-faced and normal-faced Class III, natural compensation elongates the symphysis and influences lower incisor position.

Purpose: To compare patterns of surgical change and postsurgical relapse between patients with mandibular setback surgery with minimal orthodontic preparation (MS-MO) and those with sufficient orthodontic preparation (MS-SO) after upper premolar extraction (UPE)., Materials and Methods: Twenty-six patients were allocated to 2 groups based on the duration of presurgical orthodontic preparation: MS-MO/UPE (n = 15; 5.53 ± 3.14 months) and MS-SO/UPE (n = 11; 13.00 ± 5.33 months). Lateral cephalograms were taken during the initial examination (T0), at splint removal (4 weeks after surgery; T1), and immediately after debonding (T2). To evaluate the surgical changes (T1 vs. T0) and relapse (T2 vs. T1), linear, angular, and dental measurements were used and analyzed using paired t test and independent t test., Results: Although there was no significant difference in skeletodental patterns at T0 between the 2 groups, the MS-MO/UPE group showed a significantly larger amount of mandibular setback than the MS-SO/UPE group from T0 to T1. The 2 groups exhibited significant anterior and superior movement of the mandible from T1 to T2. However, the MS-MO/UPE group manifested greater counterclockwise rotation and forward movement of the mandible than the MS-SO/UPE group. Owing to such relapse of the mandible, the MS-MO/UPE group exhibited limited retraction of the upper incisors, whereas the MS-SO/UPE group showed slight labioversion of the upper incisors., Conclusion: Compared with the MS-SO/UPE group, the MS-MO/UPE group showed a larger amount of surgical setback and greater postsurgical counterclockwise rotation and forward movement of the mandible., (Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of this study was to evaluate the influence of general anesthesia on centric jaw relation (CR) records of orthognathic surgical patients in different postural positions., Materials and Methods: Fifty patients undergoing orthognathic surgery at Taleghani Hospital (Tehran, Iran) in 2008 were prospectively studied. CR records were obtained in conscious patients in 2 different positions (upright and supine) 1 day before surgery and in the supine position under general anesthesia. The impressions were made and the corresponding casts were mounted on a semiadjustable articulator. Differences were measured to the nearest 0.10 mm using a caliper. Paired t test and a general linear regression model were used for statistical analysis., Results: Fifty patients (27 women and 23 men; mean age, 22.5 ± 3.5 yr) were enrolled. Angle Class I (group I), Class II (group II), and Class III (group III) malocclusions were detected in 16% (n = 8), 54% (n = 27), and 30% (n = 15) of patients, respectively. Although mean changes were smaller than 2 mm, statistically significant differences were found by paired t test in all Angle classification groups. No significant differences were found between the supine and conscious and the supine and unconscious patient positions in groups I and III (P > .05). However, in group II, this difference was statistically significant (P = .001). Regarding the impact of anesthesia on CR records of patients with different Angle classes, this study showed a significant effect, particularly in group II. Assessment of the outcome of interest (difference between the supine and conscious and the upright and conscious positions) versus position after adjustment for Angle class using a general linear regression model showed that the difference was significant only for Angle class (β = +0.29; t = 3.05; P = .003)., Conclusion: General anesthesia may not adversely affect the mandibular condylar position in orthognathic patients in a supine position compared with a supine and conscious position. However, among all study groups, group II showed more significant changes in CR records under general anesthesia. Oral and maxillofacial surgeons should be well aware of such changes in these particular positions and avoid possible mismanagement and potential complications., (Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Introduction: This study was conducted to measure the dimensional changes in the cranial base and the mandible in patients with facial asymmetry and mandibular prognathism, and to examine the morphologic relationship between asymmetries of the cranial base and the mandible., Methods: The patients were 60 adults with mandibular prognathism, divided into a symmetry group (menton deviation, <2 mm; n = 30) and an asymmetry group (menton deviation, >4 mm; n = 30) according to the degree of menton deviation. Three-dimensional computed tomography scans were obtained with a spiral scanner. Landmarks were designated on the reconstructed 3-dimensional surface models. Linear, angular, and volumetric measurements of the cranial base and mandibular variables were made., Results: In the asymmetry group, the hemi-base, anterior cranial base, and middle cranial base volumes were significantly larger (P <0.01), and crista galli to sphenoid, sphenoid to petrous ridge, anterior clinoid process to petrous ridge, and vomer to petrous ridge lengths were significantly longer (P <0.05) on the nondeviated side than on the deviated side. Menton deviation was significantly correlated with the difference in hemi-base volume, and ramal volume was significantly correlated with the difference in hemi-base and middle cranial base volumes between the nondeviated and deviated sides (P <0.05)., Conclusions: In patients with facial asymmetry and mandibular prognathism, cranial base volume increased on the nondeviated side and was also correlated with mandibular asymmetry., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objectives: To compare 2D:4D ratio which is determined by testosterone levels with patients having orthognathic, retrognathic and prognathic mandibles., Materials and Methods: The study was performed at Chennai, on 320 subjects of which, 60 subjects (32 males and 28 females) had retrognathic mandible; 55 subjects (25 males and 30 females) had prognathic mandible and 205 subjects (98 males and 107 females) had normal mandible. All the subjects had a normal maxilla and were in the age group of 18 to 25 years. 2D:4D ratio was determined using the photocopies of the ventral surface of right hand made with vernier calipers of 0.01 mm accuracy. Statistical analysis was undertaken using Student's t- test, ANOVA test and TukeyHSD test., Results: (i) Low 2D:4D is seen in subjects with mandibular prognathism, (ii) Among females, low 2D:4D is seen only in prognathic mandible., Conclusion: These findings highlight the fact that testosterone plays an important role in mandibular growth. Thus 2D:4D, a least invasive and reproducible procedure can be used as an early marker for mandibular progathism, and as a diagnostic tool in correlating the mandibular growth with causal relations between hormones and craniofacial development.

Introduction: Class III malocclusion is characterized by a composite of dentoskeletal patterns that lead to the forward positioning of the mandibular teeth in relation to the maxillary teeth and a concave profile. Environmental and genetic factors are associated with this condition, which affects 1% of the population in the United States and imposes significant esthetic and functional burdens on affected persons. The purpose of this study was to capture the phenotypic variation in a large sample of white adults with Class III malocclusion using multivariate reduction methods., Methods: Sixty-three lateral cephalometric variables were measured from the pretreatment records of 292 white subjects with Class II malocclusion (126 male, 166 female; ages, 16-57 years). Principal component analysis and cluster analysis were used to capture the phenotypic variation and identify the most homogeneous groups of subjects to reduce genetic heterogeneity., Results: Principal component analysis resulted in 6 principal components that accounted for 81.2% of the variation. The first 3 components represented variation in mandibular horizontal and vertical positions, maxillary horizontal position, and mandibular incisor angulation. The cluster model identified 5 distinct subphenotypes of Class III malocclusion., Conclusions: A spectrum of phenotypic definitions was obtained replicating results of previous studies and supporting the validity of these phenotypic measures in future research of the genetic and environmental etiologies of Class III malocclusion., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: To evaluate the impact of the incisor position on the self-perceived psychosocial impacts of malocclusion among Chinese young adults., Materials and Methods: This cross-sectional study included a convenience sample of 17.1- to 22.3-year-old young adults (n = 1005). The five groups represented were normal occlusion as well as incisor Class I, Class II/1, Class II/2, and Class III malocclusion. For clinical assessment, the incisor relationship was evaluated according to the British Standards Institute Incisor Classification, and the self-perception of dental esthetics was assessed using the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). Statistical analysis involved the analysis of variance and Tukey multiple-comparison post hoc tests., Results: Psychosocial impacts were different among the five groups for the four PIDAQ domains (P < .001 for all four domains). Statistically significant differences were found between the four malocclusion groups and the normal occlusion group in all four domains (P < .001 for all four domains). Furthermore, statistically significant differences were found between four malocclusion groups., Conclusions: All four malocclusion groups had more severe psychosocial impacts than the normal occlusion group in the four PIDAQ domains. Statistically significant differences were also found between the four malocclusion groups; these malocclusion groups ranked by score, highest to lowest, were Class III, Class II/1, Class II/2, and Class I.

The aim of the present study was to evaluate the association of tongue posture with the dentoalveolar maxillary and mandibular morphology in a group of Class III subjects in comparison to a group of Class I subjects. Twenty Class III subjects (9 males, 11 females, 19.2 ± 4.6 years) and 20 Class I subjects (6 males, 14 females, 17.4 ± 1.7 years) were included in the present study. Maxillary and mandibular morphology was defined by the intermolar and intercanine distances, at both the cusps and gingival levels, and by measuring surface area and volume of the palatal vault and mouth floor assessed on three-dimensional digital models. Tongue-to-palate distances were measured on lateral cephalograms. The groups were compared using the Mann-Whitney U-test and correlations between each morphological parameter and the tongue-to-palate distances were calculated using the Spearman correlation coefficient. The mandibular intermolar width at the gingival level was significantly greater in the Class III group (P < 0.01), while the maxillary intercanine widths were significantly smaller in the Class III group (P < 0.05). The mouth floor area and volume and the respective ratios between the mouth floor and palate were significantly greater in the Class III group (P = 0.01). The tongue-to-palate distances were generally greater, i.e. lower tongue posture, for the Class III subjects. Significant correlations were seen between tongue-to-palate distances in the posterior region with the area ratio (rho = 0.44, P < 0.05). Tongue posture is significantly lower in Class III subjects and is associated with the dentoalveolar characteristics of the maxilla and mandible.

Objective: To determine and compare the mean values of various intra-arch distances in Class I, Class II division 1 and Class II division 2 patients., Materials and Methods: The search engines PubMed, Embrace and Cochrane were employed to select articles for further study, and the sample thereby selected comprised adult subjects with full permanent dentition, without missing teeth, malformations or previous orthodontic treatment. Only subjects from articles published during the last 10 years were included in the study., Results: The search located a total of 628 articles regarding arch form. However, only eight articles were chosen for the study. We observed that: the distance between mandibular canines is smaller in Class I than in Class II division 1; mandibular inter-molar distance is similar in Class I and Class II division 1; maxillary inter-canine distance is similar in Class I, Class II division 2 and Class II division 1; maxillary inter-premolar width is greater in Class I than in Class II division 1; and that maxillary inter-molar width is similar in Class I and Class II division 2., Conclusions: No statistically significant differences in arch width were found between the different classes analysed (there are only slightly differences between classes), except in the case of mandibular inter-canine width (L3), which was smaller in Class I than in Class II,1, and maxillary inter-premolar width (U4), which was smaller in Class II-I than in Class I., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Introduction: The objective of this study was to characterize the volume and the morphology of the pharyngeal airway in adolescent subjects, relating them to their facial skeletal pattern., Methods: Fifty-four subjects who had cone-beam computed tomography were divided into 3 groups-skeletal Class I, Class II, and Class III-according to their ANB angles. The volumes of the upper pharyngeal portion and nasopharynx, and the volume and morphology of the lower pharyngeal portion and its subdivisions (velopharynx, oropharynx, and hypopharynx) were assessed with software (version 11.5; Dolphin Imaging & Management Solutions, Chatsworth, Calif). The results were compared with the Kruskal-Wallis and the Dunn multiple comparison tests to identify intergroup differences. Correlations between variables assessed were tested by the Spearman correlation coefficient. Correlations between the logarithms of airway volumes and the ANB angle values were tested as continuous variables with linear regression, considering the sexes as subgroups., Results: The minimum areas in the Class II group (112.9 ± 42.9, 126.9 ± 45.9, and 142.1 ± 83.5 mm(2)) were significantly smaller than in Class III group (186.62 ± 83.2, 234.5 ± 104.9, and 231.1 ± 111.4 mm(2)) for the lower pharyngeal portion, the velopharynx, and the oropharynx, respectively, and significantly smaller than the Class I group for the velopharynx (201.8 ± 94.7 mm(2)). The Class II group had a statistically significant different morphology than did the Class I and Class III groups in the velopharynx. There was a tendency to decreased airway volume with increased ANB angle in the lower pharyngeal portion, velopharynx, and oropharynx. In the upper pharyngeal portion, nasopharynx, and hypopharynx, there seemed to be no association between the airway volume and the skeletal pattern., Conclusions: The Class II subjects had smaller minimum and mean areas (lower pharyngeal portion, velopharynx, and oropharynx) than did the Class III group and significantly less uniform velopharynx morphology than did the Class I and Class III groups. A negative correlation was observed between the ANB value and airway volume in the lower pharyngeal portion and the velopharynx (both sexes) and in the oropharynx (just in male subjects)., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: The aim of this study was to determine the value of upper and lower pharyngeal depth among patients with skeletal Class III malocclusion on lateral cephalograms, as well as to examine the relationship between SNA, SNB, and ANB angles, along with Wits appraisal and the cross-sectional value of upper airway space at the level of the soft palate and tongue base among patients with skeletal Class I and III., Materials and Methods: The material consisted of lateral cephalograms taken from 80 patients living in the Lubelskie voivodeship. The study group consisted of cephalograms of 50 patients with skeletal Class III malocclusion (17 male and 33 female), whereas the control group consisted of 30 roentgenograms of patients with Class I malocclusion with proper jaw to mandible relation (14 maleand 16 female). The study and the control group shared no statistically significant differences considering basic sociographic data such as gender (chi = 1.267, p = 0.26)and age (U = 727.5, p = 0.82). The upper and lower pharyngeal depths were assessed with the use of McNamara's method. Spearman's rho test, Mann--Whitney's U test, and chi test were used for statistical analysis., Results: Among both males and females the pharyngeal depths were greater considering patients with skeletal Class III in comparison to patients with Class Imalocclusion (p < 0.001). Furthermore, it was determined that the lower as well as the upper pharyngeal width is statistically significantly dependent on ANB and SNB angles and Wits appraisal (p < 0.001)., Conclusions: Pharyngeal width at the level of the soft palate and tongue base depends on skeletal class, namely ANB angle and Wits appraisal; it increases with the increase of SNB angle (forward movement of the mandible). The SNA angle (position of the maxilla) does not influence the anterior-posterior nasopharyngeal dimension.

Statement of Problem: The closest speaking space (CSS) together with the vertical overlap of anterior teeth during the production of the /s/ sound have not been previously investigated with respect to differences in dental and skeletal orthodontic classifications., Purpose: The purpose of this study was to investigate the CSS in dental and skeletal occlusions and to analyze the cause and effect relationship of the CSS and the amount of the vertical overlap of anterior teeth., Material and Methods: Poly vinylsiloxane interocclusal registration material was placed bilaterally onto the occlusal surfaces of premolar and molar teeth of 155 native Turkish speaking adolescent and young adult dentate participants, who were then asked to pronounce the word seyis. The thinnest point between the maxillary and mandibular teeth was recorded in millimeters as the CSS. The occlusion of each participant was classified according to the Angle dental and Steiner skeletal classifications. The differences in CSS values within each classification were statistically analyzed with the Kruskal-Wallis test, and the correlation between the CSS and the vertical overlap was statistically analyzed with the Spearman Rho Correlation tests (P<.05)., Results: The differences in the CSS were only significant between Angle Class II division 2 and Class III groups (P=.034), while the differences in the CSS between skeletal classes were not significant. The correlation between the amount of CSS and the amount of vertical overlap was not significant., Conclusions: The results showed that regardless of dental and skeletal occlusions, average CSS values could be used to determine the occlusal vertical dimension of prosthetic restorations., (Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.)

Statement of Problem: Few cephalometric analyses have been put forward to assess the treatment outcome after orthodontic treatment. However, these analyses are somewhat complicated and time consuming. The Tetragon analysis is introduced with measurement of treatment outcome as one of its objectives., Purpose of Study: The study was undertaken to evaluate the treatment outcome by checking the skeletal and dental changes using pretreatment and post-treatment radiographs and to evaluate the efficiency of treatment in the Department of Orthodontics, College of Dental Sciences, Davangere, using the Tetragon analysis., Materials and Methods: Records of 35 finished patients with fixed orthodontic therapy using preadjusted edgewise appliance were selected. The samples were analyzed separately for the skeletal parameters consisting of skeletal class I, II and III using Tetragon analysis., Results: The post-treatment reduction of upper incisor palatal plane angle was found to be statistically significant in skeletal class I (p < 0.01) and skeletal class II patients (p < 0.05). The post-treatment increase in interincisal angle was found to be statistically significant in skeletal class I (p < 0.01) class II patients (p < 0.05)., Conclusion: Fixed appliance therapy reduced the proclination of upper incisors and increased the interincisal angle in skeletal class I and II cases but not in skeletal class III cases. The lower incisal angulation and the maxilla-mandibular plane angle did change significantly and so were the angles of the Trigon. The Tetragon analysis proved easy to measure the treatment outcome.

Introduction: Osteogenesis imperfecta is a heritable disorder affecting bone and tooth development. Malocclusion is frequent in those affected by osteogenesis imperfecta, but this has not been studied in detail. The purpose of this study was to describe and quantify the severity of malocclusions in patients with osteogenesis imperfecta., Methods: Articulated dental casts were obtained from 49 patients diagnosed with osteogenesis imperfecta (ages 5-19 years; 28 female) and 49 age- and sex-matched control subjects who did not have osteogenesis imperfecta. Both groups were seeking orthodontic treatment. Malocclusions were scored by using the peer assessment rating (PAR) and the discrepancy index (DI)., Results: The average United Kingdom weighted PAR scores were 31.1 (SD, 14.5) for the osteogenesis imperfecta group and 22.7 (SD, 10.7) for the control group (P <0.05). The mean United States weighted PAR scores were 32.2 (SD, 15.0) for patients with osteogenesis imperfecta and 21.6 (SD, 9.6) for the controls (P <0.05). The average modified DI scores were 29.8 (SD, 20.2) for the osteogenesis imperfecta group and 12.4 (SD, 6.8) for the control group (P <0.05). Group differences were greatest for lateral open bite (osteogenesis imperfecta group, 7.1; control group, 0.3) for the DI parameters and anterior crossbite (osteogenesis imperfecta group, 13.0; control group, 3.8 [United Kingdom]) for the PAR., Conclusions: Both the PAR and the DI showed that malocclusions were significantly more severe in patients with osteogenesis imperfecta than in the control group. There was a higher incidence of Class III malocclusion associated with anterior and lateral open bites in patients affected by osteogenesis imperfecta., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

In orthodontic diagnosis and treatment planning, an accurate antero-posterior measurement of jaw relationships is critically important. Previously described angular and linear measurements can be inaccurate because of their dependency on various factors. The purpose of this study was to introduce a new cephalometric measurement, named the W angle, to assess the sagittal relationship between maxilla and mandible with accuracy and reproducibility. This angle uses three skeletal landmarks--point S, point M, and point G--to measure an angle that indicates the severity and the type of skeletal dysplasia in the sagittal dimension. One hundred and forty-two pre-treatment cephalometric radiographs of patients between the age of 15 and 25 years were selected. They were again subdivided into Classes I, II, and III groups on the basis of Beta angle, Wits appraisal, and ANB angle. The W angle was measured between the perpendicular from point M on S-G line and the M-G line. The mean and the standard deviation for the W angle were calculated. After using the one-way analysis of variance and the Newman-Keuls test, receiver operating characteristics curves were obtained. Results showed that a patient with a W angle between 51 and 56 degrees can be considered to have a Class I skeletal pattern. With an angle less than 51 degrees, patients are considered to have a skeletal Class II relationship and with an angle greater than 56 degrees, patients have a skeletal Class III relationship.

Maxillary deficiency is one of the facial features of Down syndrome (DS). Differences in craniofacial morphology between DS and nonsyndromic skeletal Class III malocclusion with maxillary deficiency remain unclear. This study compared the craniofacial differences of white male children from Central-Western Brazil with DS (n = 30, mean age: 8 years 3 months), skeletal Class III profile with maxillary deficiency (n = 30, mean age: 7 years 9 months), and skeletal Class I profile (n = 30, mean age: 8 years 2 months), using lateral cephalometric radiographs. The differences among the three groups were compared with analysis of variance and Tukey's tests. The DS group showed reduced anterior cranial base (S-N, P < 0.001] and facial dimensions (Co-Gn, N-Me, N-ANS, and ANS-Me, P < 0.001), except in posterior dimensions (S-Go, P < 0.005; Ar-Go, P > 0.005). Maxillary length (Co-A, P < 0.001) and facial convexity (NAP, P < 0.005) were reduced when compared with the control group, although maxillary position to cranial base (SNA, P < 0.005) was within the normal range. A flattened cranial base (BaSN, P < 0.001) also contributed to differentiating DS from nonsyndromic groups. The group with maxillary deficiency showed a more unfavourable maxillomandibular relationship (MMD, P < 0.001) and a mandibular protrusion (SNB, P < 0.001). Subjects with DS differed from Class III with maxillary deficiency with respect to the flatter cranial base and reduced maxillary length. Maxillary deficiency was not so expressive in the face of DS subjects because of the overall reduction in craniofacial dimensions.

Introduction: Individual planning of complex maxillofacial corrections may require 3D models which can be manufactured based on DICOM datasets. The gold standard for image acquisition is still high-resolution multi-slice computed tomography (MSCT). However, appropriate datasets for model fabrication can be acquired by modern Cone-Beam CT (CBCT) devices that have been developed specifically for maxillofacial imaging. The clinical utility of individual models fabricated on the basis of CBCT datasets was assessed., Methods: In five patients affected by different deficiencies of the maxillofacial skeleton, preoperative imaging was performed with ILUMA CBCT. Segmentation of hard tissues was performed manually by thresholding. Corresponding STL datasets were created and exported to an industrial service provider (Alphaform, Munich, Germany) specializing in rapid prototyping, and 3D models were fabricated by the selective laser sintering (SLS) technique. For variance analysis, landmark measurements were performed on both virtual and 3D models. Subsequently, maxillofacial surgery was performed according to the model-based planning., Results: All CBCT-based DICOM datasets could be used for individual model fabrication. Detailed reproduction of individual anatomy was achieved and a topographic survey showed no relevant aberrance between the virtual and real models. The CBCT-based 3D models were therefore used for planning and transfer of different maxillofacial procedures., Conclusions: CBCT-based datasets can be used for the fabrication of surgical 3D models if the correct threshold is set. Preoperative workflow and patient comfort is improved in terms of the fast-track concept by using this "in-house" imaging technique.

Angle Class III malocclusions are not so frequently met but they raise big problems of treatment. The analyzed case represents a 14-year-old patient that came to the dental consulting room with an Angle Class III malocclusion determined by the excess of the somatotropic pituitary hormone and a gingival hyperplasia more emphasized at the level of inferior frontal teeth. The patient followed a fixed appliance treatment, the straight-wire technique. All along the treatment and after it, the hyperplasia and the gingival inflammation not only maintained but they even got worse. Thus, an improper hygiene associated with a severe Angle Class III malocclusion maintains and aggravates the gingivitis. The histological and immunohistochemical study of the gingiva revealed important epithelial modifications that led to an epithelial hypertrophy with a tendency toward acanthosis and to severe epithelial erosions. An inflammatory chronic process (rich in lymphocytes, plasma cells and macrophages full of angiogenesis vessels) and an intense reaction of the fibroblastic cells appeared in the gingival corium.

This report describes the treatment of a 16-year-old girl with a severe transverse dental arch discrepancy resulting from a mildly constricted maxillary arch and an overexpanded mandibular arch. The patient had a Class I skeletal relationship, a high mandibular plane angle, a Class III molar relationship, bilateral posterior crossbites, and deviated midlines. A 3-dimensional digital setup was used to assist treatment planning. The digital setup allowed us to evaluate multiple treatment options before deciding on the most suitable one for the patient. The final treatment protocol consisted of extraction of upper second premolars and lower first molars due to enamel hypoplasia. Starting with the leveling and alignment stage of treatment, the maxillary archwires were expanded and the mandibular wires were constricted to correct the transverse discrepancy. An auxiliary expansion arch was used to achieve overcorrection. The active treatment period was 24 months. Proper overbite and overjet, facial balance, and good occlusion were achieved., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: The aim of this study was to evaluate of the patterns of post-surgical relapse after mandibular setback surgery with minimal orthodontic preparation (MS-MO)., Materials and Methods: The subjects consisted of 15 patients with minimal pre-surgical orthodontic preparation (1.37 ± 1.69 months). Lateral cephalograms were taken in pre-surgical (T0), post-surgical 1 month (T1) and immediately after debonding (T2) stages. To evaluate the surgical changes (T1-T0) and the relapse (T2-T1), the linear and angular measurements were analyzed using paired t-test. Pearson's correlation coefficients of the horizontal and vertical relapses of Pog and Me to other measurements were calculated. Pog or Me in T1 were displaced rotationally on Ar-Pog or Ar-Me lines in T2 to evaluate the remaining surgical relapse except the rotational relapse from total relapse., Results: The mandible relapsed anteriorly 3.53 mm (Pog) and 4.00 mm (Me) and superiorly 2.72 mm (Pog) and 2.44 mm (Me). FH to Ar-Pog and FH to Ar-Me decreased by about 2°. Pure surgical relapses at Pog and Me, except rotational relapses, were about 0.5 mm anteriorly and inferiorly 0.8 mm., Conclusion: The vertical relapse might induce mandibular rotation with the horizontal relapse. For an accurate prediction after MS-MO, the rotational relapse might be considered., (Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.)

Objective: This study has investigated two new cephalometric variables, the Pi angle and Pi linear in the evaluation of anteroposterior skeletal discrepancy., Design: Retrospective cross-sectional study., Setting: Manipal College of Dental Sciences, Manipal, India, Subjects and Method: A sample of 155 subjects (mean age 19·7 years) were subdivided into skeletal class I, II and III groups based upon ANB angle. Descriptive data were calculated for each variable and group. Receiver operating characteristics curves were used to examine sensitivity and specificity of the Pi angle in the discrimination between different skeletal groups. Correlation coefficients were obtained for each of the parameters to compare their relationship with other parameters in the class I group. Coefficient of determination, regression coefficient, regression equation and standard error of estimate were also calculated from the parameters showing significant correlation with the Pi angle., Results: Mean values for the Pi angle in skeletal class I, II and III subjects were 3·40 (±2·04), 8·94 (±3·16) and -3·57 (±1·61) degrees, respectively. For the Pi linear they were 3·40 (±2·20), 8·90 (±3·56) and -3·30 (±2·30) mm for class I, II and III subjects, respectively. Receiver operating characteristic curves showed that a Pi angle greater than 5 degrees had 89% sensitivity and 82% specificity for discriminating a skeletal class II group from class I. A Pi angle of less than 1·3 degrees had 100% sensitivity and 84% specificity in discriminating skeletal class III groups from class I. The overall accuracy for discriminating class II groups from class I was 85% and for class III from class I, 90%. Thus, a cut-off point between class I and II groups could be considered a Pi angle of approximately 5 degrees and between class I and class III, approximately 1·3 degrees. There were no statistically significant correlations found between Pi angle and ANB (0·07), Beta angle (-0·04) and WITS analysis (0·19). The highest level of correlation was obtained for the Pi angle and Pi linear (0·96)., Conclusion: The anglar and linear components of the Pi analysis are a suitable method for assessing anteroposterior jaw discrepancy in daily clinical practice.

Background/aim: Skeletal Class III malocclusion is a discrepancy in the sagittal jaw relationship, due to imbalances in their development and/or position, resulting in the dominant appearance of the lower jaw in facial profile. The aim of this study was to determine variations in the sagittal position of the jaw bones to the cranial base in subjects with skeletal Class III, for the earliest possible diagnosis of malocclusion., Methods: Fifty children and as many adults with skeletal Class III, both sexes, were examined and selected, based on the findings of sagittal interjaw relationship (ANB) < or = 0 degrees from the cephalometric analysis of tele-x-ray profile head shots. The subjects were grouped according to age. The first group consisted of children aged 6-12 years, and another group, of adults aged 18-26 years. We measured the angles of maxillary prognathism (SNA), mandibular prognathism (SNB) and ANB. Based on these results, within the respective groups subclassification into the subgroups was done, among which a significant difference measured values was evaluated. In both groups a significant correlation of the determined values was evaluated., Results: An average SNA angle ranged 77.36 +/- 3.58 in children and 77.32 +/- 4.88 in adults, while an average SNB angle was 79.46 +/- 3.91 in the group of children and 81.12 +/- 3.76 in adults. An average ANB angle was -2.10 +/- 2.07 in children, and -4.00 +/- 2.34 in adults. In both groups, a significant correlation between the measured values and a significant difference in the values of all the measured parameters were found between patients from different subgroups (p < 0.01)., Conclusion: The most common morphological variation of sagittal position of the upper jaw is its retrognatism, which is equally present in both children and adults. Sagittal position of the lower jaw in most of the adults was prognathic, while mandible prognathism in the children was less present.

Introduction: Resorbable screw fixation for orthognathic surgery is widely used in oral and maxillofacial surgery and has several advantages. However, surgeons are concerned about using resorbable screws in orthognathic surgery because of possible postoperative complications such as relapse, screw fracture, and infection. The purpose of this study was to evaluate the skeletal stability of bicortical resorbable screw fixation after sagittal split ramus osteotomies for mandibular prognathism., Materials and Methods: This study included 25 patients who underwent mandibular setback surgery fixed with resorbable screws after sagittal split osteotomy at the Department of Oral and Maxillofacial Surgery at Seoul National University Dental Hospital. Five resorbable screws (Inion CPS(®), Inion Ltd., Finland) were applied bicortically at each osteotomy site via a transbuccal approach. No rigid intermaxillary fixation was applied on the first postoperative day. Passive mouth opening exercises were allowed, using two light, rubber elastics for guidance. The control group was 25 patients fixed with four titanium screws. The follow-up period was 12-22 months (mean 17.8 months). Postoperative skeletal changes on lateral cephalometric radiographs were analyzed and compared between the two groups preoperatively, immediately postoperatively, and 6 months postoperatively., Results: The average setback was 6.9 mm and no major intraoperative complications occurred. One patient experienced infection immediately after surgery that was controlled uneventfully. The data did not demonstrate any significant difference in postoperative skeletal stability between the two groups. Differences between the immediate postoperative state and 6 months after surgery were not significant. In earlier cases, especially for patients with severe mandibular prognathism, immediate postoperative elastic traction was needed for stable occlusal guidance., Conclusions: The results of this study indicate that bicortical resorbable screws offer a clinically stable outcome for the fixation of mandibular sagittal split osteotomies in mandibular prognathism. However the resorbable screws showed less stable results vertically than the titanium screws., (Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

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

It is incumbent upon the orofacial myologist to evaluate the presenting client's occlusion and detect any behaviors which may be influencing the alignment of the dentition or interfering with the treatment plan of the referral source. In order to accomplish these tasks, it is necessary to share some common terminology and to effectively communicate between all the participants involved in the treatment plan. The purpose of this article is to assist in accomplishing these goals.

Class 3 patients may have relatively high prevalences of temporomandibular disorders; therefore, joint morphology can be important for their orthodontic-surgical treatments. The aim of this study was to evaluate the relationship between facial height and TMJ morphology in skeletal class 3 patients.