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AIM Evaluation of size of the condyle in various vertical and anteroposterior skeletal conditions with the help of cone-beam computed tomography (CBCT). METHODS AND MATERIALS In this study, 266 study participants were included consisting of 112 males and 144 females. The study participants were categorized as class I when -1° ≤ A point-nasion-B point angle (ANB) < 4°, class II when ANB ≥ 4°, and class III when ANB < -1°. The study participants were categorized as hypodivergent when the mandibular plane (MP) ≤ 23°, normodivergent when 23° < MP < 30°, and hyperdivergent when MP ≥ 30°. CBCT images were obtained for each subject and measurement of length, width, and height of the condyle was carried out. The data were collected and analysis of covariance test (ANCOVA) was used for statistical analysis. Statistical significance was adjusted at p ≤ 0.05. RESULTS The size of the condyle was smaller in females. The length of the condyle was similar in different anteroposterior and vertical positions with no significant difference. The width of the condyle and the height of the condyle were greatest in class III anteroposterior condition while they were lowest in class I condition. The width and height of the condyle were greatest in hypodivergent condition while they were lowest in hyperdivergent condition. CONCLUSION It was concluded that the height and width of the condyle vary considerably in different vertical and anteroposterior skeletal patterns and the size of the condyle was smaller in women as compared with men. CLINICAL SIGNIFICANCE The position of the condyle and its morphology are important features that constitute an important part of orthodontic treatment planning. The skeletal pattern of the patient has also an important effect on the diagnosis, planning of treatment, and prognosis in the orthodontic treatment.

PURPOSE To study the changes of hyoid position in infants with Robin sequence before and after mandibular distraction osteogenesis, and to explore the related factors. MATERIAL AND METHODS Twenty-six infants with Robin sequence underwent bilateral mandibular distraction osteogenesis from May 2016 to April 2020. Three-dimensional computed tomography data of patients before and after surgery were analyzed with Materialise Mimics 17.0. Changes in the three-dimensional position of the hyoid bone were studied. RESULTS The angle between the long axis of the tongue body and hard palate plane, and the angle between the long axis of the tongue body and mandibular plane were significantly decreased after surgery than before surgery. The hyoid bone-cranial base vertical distance, hyoid bone-mental point distance, and hyoid bone-epiglottis distance were significantly increased after surgery. The differences in the above-mentioned data were statistically significant (P

Uvod: Cilj našeg istraživanja bio je otkriti kolika će biti promjena nagiba protetske plohe nakon petogodišnjeg nošenja potpune proteze. Materijali i metode: U istraživanju je sudjelovalo 20 ispitanika. Svakome od ispitanika napravljena su dva lateralna kefalograma. Prvi kod predaje proteze, a drugi nakon petogodišnjeg nošenja proteze. Snimanja su obavljena na rendgenskom aparatu (Siemens Roentgen Kugel 2E), a svi rendgen-filmovi bili su od istog proizvođača (AGFA-ORTHO CP-G PLUS), dobiveni na sličan način u istoj kutiji pomoću razvijača istog proizvođača (AGFA G 138 i). Ručnim precrtavanjem s telerendgenogramom na paus-papir s 3H crtaćom olovkom prikupljeni su kefalometrijski podaci. Sva detaljnija mjerenja rađena su uz pomoć precizne pomične mjerke (MEBA, Zagreb, Hrvatska). Statistički izračun je napravljen pomoću programa SPSS 12.0. (Statistical package for Social Science, Chicago, Illinois, USA). Rezultati: Rezultati nam ukazuju da je došlo do statistički značajnih promjena kutova protetske plohe u odnosu na mandibularnu (Me-Go), palatinalnu (ANS-PNS) i frankfurtsku horizontalu (Po- Or) tijekom petogodišnjeg nošenja proteze. Zaključak: Kod svih sudionika tijekom petogodišnjeg nošenja potpune proteze dolazi do statistički značajne promjene kuta protetske plohe. Nužna je izrada nove potpune proteze zbog narušene funkcionalnosti uslijed promjene nagiba protetske plohe., Aim: The aim of our study was to find out what the change in the slope of the prosthetic plane will be after five years of wearing a complete prosthesis. Materials and Methods: A total of 20 subjects participated in the study. Two lateral cephalograms were performed for each of the subjects, the first when the prosthesis was placed, and the second after five years of prosthesis wearing. Imaging was performed on an X-ray machine (Siemens Roentgen Kugel 2E), with all X-ray films being from the same manufacturer (AGFA-ORTHO CP- G PLUS) and obtained in a similar manner, in the same box using a developer produced by the same manufacturer (AGFA G 138 i). Cephalometric data were collected by manually tracing a teleroentgenogram on tracing paper with a 3H pencil. All detailed measurements were made using a precision sliding caliper (MEBA, Zagreb, Croatia). The statistical calculation was made using the SPSS 12.0 program (Statistical Package for Social Science, Chicago, Illinois, USA). Results: The results point to the fact that there were statistically significant changes in the angles of the prosthetic plane in relation to the mandibular (Me-Go), palatal (ANS-PNS), and Frankfurt horizontal plane (Po-Or) during the five-year-long prosthesis wearing. Conclusion: A statistically significant change in the angle of the prosthetic plane occurred in all participants during the five-year-long wearing of a complete prosthesis. New complete prostheses were required due to impaired functionality given the changes in the slope of the prosthetic surface.

This paper aimed to offer a way to recover the loss of anterior torque, deepbite, and the deep and reverse curve of Spee that occurred during space closure in skeletal Class II malocclusion. A female patient with a skeletal Class II pattern and the steep mandibular plane was treated with temporary skeletal anchorage devices (TSADs), accentuated and reversed curve nickel-titanium archwires and TSAD-anchored Class II elastics. After treatment, the patient's occlusion significantly improved, and the results were stable at five years posttreatment. The combined use of TSADs and continuous archwires with accentuated and reverse curve could be a reliable and effective treatment modality for torque control and intrusion of retro-clined incisors and leveling of the curve of Spee.

Objective To investigate dimensional changes in regional pharyngeal airway spaces after premolar extraction in bimaxillary skeletal protrusion (BSP) patients according to vertical skeletal pattern, and to further identify dentoskeletal risk factors to predict posttreatment pharyngeal changes. Methods Fifty-five adults showing BSP treated with microimplant anchorage after four premolar extractions were included in this retrospective study. The subjects were divided into two groups according to the mandibular plane steepness: hyperdivergent (Frankfort horizontal plane to mandibular plane [FH-MP] ≥ 30) and nonhyperdivergent groups (FH-MP < 30). The control group consisted of 20 untreated adults with skeletal Class I normodivergent pattern and favorable profile. Treatment changes in cephalometric variables were evaluated and compared. The association between posttreatment changes in the dentoskeletal and upper airway variables were analyzed using linear regression analysis. Results The BSP patients showed no significant decrease in the pharyngeal dimensions to the lower level in comparison with controls, except for middle airway space (MAS, p < 0.01). The upper airway variable representing greater decrease in the hyperdivergent group than in the nonhyperdivergent group was the MAS (p < 0.01). Posttreatment changes in FH-MP had negative correlation with changes in MAS (β = -0.42, p < 0.01) and inferior airway space (β = -0.52, p < 0.01) as a result of multivariable regression analysis adjusted for sagittal skeletal relationship. Conclusions Decreased pharyngeal dimensions after treatment in BSP patients showed no significant difference from the normal range of pharyngeal dimensions. However, the glossopharyngeal airway space may be susceptible to treatment when vertical dimension increased in hyperdivergent BSP patients.

Objectives: The aim of this study was to assess the role of impacted third molar angulation on the severity of anterior crowding. Materials and Methods: Panoramic radiographs and three-dimensional (3D) digital models of 45 patients satisfying the following inclusion criteria were selected for this study. To calculate the irregularity index of Little, the sum of the contact point displacements from the anatomical contact point to the contact point among the lower canine teeth was measured on 3D digital models. Little’s irregularity index was used to classify patients as having mild, moderate, or severe crowding. For intragroup variance, comparisons T test was used. The Spearman single rank correlation coefficients were used to analyze any correlation among degree of crowding and (a) third molar inclination to base of mandible, (b) third molar inclination to occlusal plane, and (c) third molar inclination to second molar inclination respectively. Results: There were no statistical differences found in all tested parameters (i.e., third molar inclination to mandibular plane, inclination of the third molars to occlusal plane, and inclination of the third molars to second molars) among three groups (P > 0.005). Conclusion: It can be deduced that no relationship obtains among the third molar inclination to base of mandible, third molar inclination to occlusal plane, third molar inclination to second molar inclination, and the level of anterior crowding.

Esthetics has been an ever-evolving concept and has gained considerable importance in the field of orthodontics in the last few decades. The re-emergence of the soft tissue paradigm has further catapulted the interest of the orthodontist. So much so that achieving a harmonious profile and an esthetically pleasing smile has become the ideal goal of treatment and is no longer secondary to achieving a functional dental occlusion and/or a rigid adherence to skeletal and dental norms. Esthetics in the orthodontic sense can be divided into three categories: macroesthetics, miniesthetics, and microesthetics. Macroesthetics includes the evaluation of the face and involves frontal assessment and profile analysis. The frontal assessment involves assessment of facial proportions, while the profile analysis involves evaluation of anterior–posterior position of jaws, mandibular plane, and incisor prominence and lip posture. Miniesthetics involves study of the smile framework involving the vertical tooth–lip relationship, smile type, transverse dimensions of smile, smile arc, and midline. Microesthetics involves the assessment of tooth proportions, height-width relationships, connectors and embrasures, gingival contours and heights, and tooth shade and color. The harmony between these factors enables an orthodontist to achieve the idealized esthetic result and hence these parameters deserve due consideration. The importance placed on a pleasing profile cannot be undermined and the orthodontist should aim for a harmonious facial profile over rigid adherence to standard average cephalometric norms. This article aims to give an overview of the macro, mini, and microesthetic considerations in relation to orthodontic diagnosis and treatment planning.

Introduction: The relationship between the malocclusion and the facial form has been a focus for Orthodontists since the early 20th century. Cephalometrics can be utilized to describe, compare and classify the nature of orthodontic problems. Since well-established Indian ethnic norms are lacking, norms derived for Caucasian population are routinely used for investigations. Rajasthan is one of the largest state in India and Mewar is one of the major areas of it. With the increasing number of children of Rajasthan seeking professional treatment for malocclusion, it has become apparent that there is need to determine what constitutes a pleasing or normal face for the children of Rajasthan. A comprehensive and accurate diagnostic assessment of any orthodontic patient involves the comparison of the patient’s cephalometric findings with the norms of his or her ethnic groups or racial groups or subgroups. Materials and Methods: This study was conducted on 100 lateral cephalographs which were selected from the records in the Department of Orthodontics and Dentofacial Orthopedics. Results: According to results there was a higher FMPA in males than females in Western Rajasthan population. While observing the overall result no significant difference was observed in FMPA between male and female population of Western Rajasthan. Conclusion: The present study was undertaken to develop cephalometric norms of Tweed’s diagnostic facial triangle for West Rajasthan population and to find out any variation from Caucasian standard. The result of the study indicated that separate norms should be considered forWest Rajasthan males and females during diagnosis and treatment planning. Keywords: Frankfort mandibular plane, Caucasian, Rajasthan.

Purpose To assess a potential association between lower incisor (LI) position changes during Herbst–multibracket appliance (Herbst–MBA) treatment and the development of labial gingival recessions (LGR). Methods All class II patients (Department of Orthodontics, University of Giessen, Giessen, Germany) who had undergone Herbst–MBA treatment until 2015 with study models and lateral cephalograms available from before (T0) and after treatment plus ≥24 months of retention (T3) were included (n = 259). Lateral cephalograms were evaluated regarding LI position changes: iiL/ML (angle between LI long axis and mandibular plane [MP]), ii-MLPg (distance between LI incisal edge and a line perpendicular to MP through pogonion), apex-MLPg (distance between LI apex and a line perpendicular to MP through pogonion), ii-MLii (distance between LI incisal edge and MP on a line perpendicular to MP through incisal edge). Using study models the distance between the cementoenamel junction and the deepest point of the gingival margin was defined as LGR. Results The following cephalometric mean changes were recorded (T0–T3): iiL/ML +5.9 ± 5.76° (p = 0.929), ii-MLPg −0.2 ± 0.25 mm (p = 0.430), apex-MLPg +0.1 ± 0.32 mm (p = 0.363), ii-MLii +0.1 ± 0.36 mm (p = 0.206). The mean increase of LGR magnitude measured on the study models was 0.1 ± 0.35 mm. However, no association with the cephalometric LI position changes was found (|R| ≤ 0.2). Conclusion There is no association between the amount of LI position changes and the development of LGR during Herbst–MBA treatment plus retention. Nevertheless, individual predisposition or excessive treatment changes and extraordinary treatment approaches, respectively, might still lead to development of LGR.

Background: The aim of this cross-sectional study was to compare the dimensions of mandibular symphysis (MS) between gender and the different sagittal and vertical skeletal relationships. Material and Methods: Pre-treatment records of orthodontic patients were divided according to gender, sagittal (Class I, II and III) and vertical (decreased, average and increased mandibular plane [MP] angle) skeletal relationships. Measurements of MS parameters were performed on lateral cephalograms using IMAGEJ software. Comparisons between MS parameters and gender and the different skeletal relationships was performed using multifactorial and one-way ANOVA, and independent sample t-tests. Results: A total of 104 records (25 males and 79 females) fulfilled the inclusion criteria. Males had significantly greater MS surface area, dentoalveolar length, skeletal symphysis length, total symphysis length, vertical symphysis dimension and symphysis convexity (p

Summary Aim Craniofacial growth demonstrates significant variation and is difficult to predict. The aim of the present investigation was twofold: (1) to assess the association (covariation) between craniofacial shape at pre- and post-adolescence and (2) to evaluate if pre-adolescent craniofacial shape is related (covaries) with growth magnitude and direction. Subjects and methods One hundred fifty subjects (86 males and 64 females) untreated orthodontically were selected from AAOF Craniofacial Growth Legacy Collection. Each subject had cephalograms taken before 9 (pre-adolescent stage) and after 15 years of age (post-adolescent). Fourteen curves comprising 123 points (10 fixed and 113 sliding semilandmarks) comprehensively covering the craniofacial skeleton were digitally traced on each cephalogram. Procrustes alignment, principal component analysis, 2-block partial least squares (2B-PLS) analysis, and regression analysis were done after sliding the semilandmarks to minimize bending energy. Results The first 16 principal components (PCs) were non-trivial and explained 85.2% of total shape variability in the sample. PC1 depicted mainly variability in the vertical direction, PC2 represented mostly variability in the saddle angle and in the antero-posterior position of the mandible, and PC3 depicted primarily variability of the mandibular shape (steep versus flat mandibular plane). The covariation between pre- and post-adolescent facial shape was statistically significant, both in the pooled sample (RV coefficient = 0.604) and in boys (RV = 0.639) and girls (RV = 0.629). The pre-adolescent shape was weakly associated with the magnitude of facial change—2-block PLS analysis demonstrated that blocks 1 and 2 were independent (P = 0.118, RV = 0.035). Conclusions The pre-adolescent shape of the craniofacial complex explained approximately 60% of the post-adolescent shape of the craniofacial complex; however, the relationship between pre-adolescent shape of the craniofacial complex and magnitude of its change was weak.

OBJECTIVE: To find the mean curve spee depth and association in three different skeletal vertical patterns (Hypodivergent, Normodivergent and Hyperdivergent). METHODOLOGY: Orthodontic models of mandibular arch and Lateral cephalogram of 110 patients with the mean age of 17.16±4 years, 26.4% (N=29) males and 73.6% (N=81) females were taken from the patients who visited for the orthodontic treatment, to the Department of Orthodontics of Karachi Medical and Dental College. Skeletal divergence defined by the mandibular plane (Lower border of mandible) to sella-nasion line angle (SN-MP). It was measured on lateral cephalogram and Curve of spee depth measured on mandibular cast. RESULTS:Out of 110 patients 20.9% (N= 23) were hypodivergent, 29.1% (N=32) were normodivergent and 50% (N=55) were hyperdivergent. The curve of spee among these three groups were 3.39±0.30mm, 2.62±0.23mm and 2.02±0.45mm. One-way ANOVA has been applied and it showed highly significant differences in the value of curve of spee depth among three vertical skeletal patterns with the p-value of 0.000. Moving from Hypodivergent to Hyperdivergent cases, the curve of Spee depth reduces. CONCLUSION: It has been found that there is a significant difference in curve of spee among hypodivergent, normodivergent and hyperdivergent patients. KEYWORDS: Dentistry, Curve of Spee, Vertical Skeletal Patterns, Orthodontic Diagnosis. HOW TO CITE: Rehman SA, Rizwan S, Faisal SS, Hussain SS. Association of curve of spee with vertical skeletal patterns. J Pak Dent Assoc 2020;29(4):254-258.

The aim of this study was to quantify upper airway changes following mandibular orthognathic surgery. Treatment records of 50 patients who underwent mandibular orthognathic surgery were divided into 2 groups, that is, Group 1: Cases treated with Mandibular Advancement Surgery and Group 2: Cases treated with Mandibular Setback Surgery with 25 patients in each group. The Lateral Cephalogram and Acoustic Pharyngometry records of both groups were studied at T0 (01 week before surgery) and T1 (01 year postsurgery) for changes in linear airway measurements (Nasopharyngeal Airway Space - NAS, Superior Airway Space - SAS, Posterior Airway Space - PAS and Hypopharyngeal Airway Space (HAS)), hyoid bone position (Mandibular Plane Hyoid distance), mean area and mean volume. The percentage change and change in these parameters per millimeter advancement or setback of mandible at T1 was calculated. A significant increase in linear airway parameters (SAS and PAS); decrease in hyoid distance; and increase in volume and area of upper airway was observed at T1 in Group 1 and reverse was observed in Group 2. The change in airway parameters (SAS, PAS, mean volume and area) was more significant in Group 1 as compared to Group 2. In the current airway centric approach, meticulous assessment and prediction of long-term airway changes post surgery should be an integral part of ortho-surgical diagnosis and treatment planning and suitable modifications in the treatment plan must be made to cater for any potential adverse effects on airway.

Aims and Objectives: To evaluate the association between mandibular growth pattern and soft tissue chin (STC) thickness measured at different chin levels and the gender differences in STC thickness at these different chin levels. Materials and Methods: Pretreatment lateral cephalograms of 161 subjects aged 18–45 years were selected, and subjects were divided into 4 groups depending on mandibular growth pattern defined by the mandibular plane to cranial base angle. The STC thicknesses were measured at pogonion (Pog), gnathion (Gn), and menton (Me). Group difference was evaluated using analysis of variance. Results: STC thickness was greater (p < .05) in the low-angle group, and it gradually decreased across the groups, the least being in the high-angle group. No sexual dimorphism was observed among the groups (p > .05). Conclusion: This study suggests that STC thickness measurements were smaller in high-angle group compared to low-angle group.

Objectives The location of the mandibular foramen is essential for the quality of the inferior alveolar nerve block anaesthesia and has often been studied with contradictory results over the years. The aim of this study was to locate the mandibular foramen, according to the dental age of the subject, through 3D analysis. Methods Three-dimensional images were reconstructed from mandibular computed tomography of 260 children, adolescents and adults. The occlusal plane was determined as the average plane passing through the buccal cusps of mandibular molars, premolars, and canines, and through the incisor edge. The mandibular foramen was located three dimensionally in relation to the anterior edge of the ramus (or coronoid notch), the sagittal plane and the occlusal plane. Results All along mandibular growth, the three distances defining the relative position of the mandibular foramen showed negligible changes. The mandibular foramen is located from − 0.4 to 2.9 mm above the occlusal plane. The distance between the mandibular foramen and the leading edge of the mandibular ramus ranged from 17 to 19.5 mm. The angle between the ramus and the sagittal plane ranged from 3° to 5.4°. Conclusion In our sample, and using the occlusal plane and the anterior edge of the ramus as anatomical references, the location of the mandibular foramen was considered to be similar in all patients regardless of age.

OBJECTIVE: To evaluate the therapeutic effect of using micro-implant anchorage (MIA) to rotate the functional occlusal plane (FOP) counterclockwise. METHODS: Forty skeletal class Ⅱ high-angle patients who had completed orthodontic treatment were enrolled, including 20 patients treated with MIA orthodontic system (MIA group) and the other 20 patients treated with traditional sliding straight wire appliance (control group). Cephalometric measurements on the lateral cranial radiographs before and after treatment were performed, all acquired data were statistically analyzed with SPSS 26.0. RESULTS: At the end of treatment, MIA group obtained better effect of FOP and mandibular plane counter-clockwise rotation than the control group. In the MIA group, the average change of FOP-frankfort horizontal plane (FH), FOP-SN and mandibular plane angle (MP-FH) angle was –4.5(–7.3, –3.7)°, (–4.6±3.3)° and –1.7(–3.0, –0.9)°, respectively. In the control group, the average change of FOP-FH, FOP-SN and MP-FH angle was –0.1(–4.1, 3.0)°, (–0.1±5.1)° and –0.4(–2.4, 0.7)°, respectively. There was significant difference between the change of the two groups (all P

Background: The aim of this study is to evaluate and compare, through bidimensional cephalometry, skeletal and dental changes obtained from a rapid maxillary expander (RME) and a Ni-Ti leaf spring expander (Leaf) and compare them with an untreated control group. Methods: Records consisted of lateral cephalograms obtained before and after maxillary expansion of patients that underwent orthodontic treatment at the Department of Biomedical, Surgical and Dental Sciences. The Leaf expander group consisted of 9 males (mean age = 7.5 ± 0.9 years old) and 11 females (mean age = 8.2 ± 0.6 years old). The RME group of the present study was composed of 11 males (mean age = 7.8 ± 0.6 years old) and 12 females (mean age = 8.1 ± 0.5 years old). Digital cephalograms were traced using Dolphin Imaging software v.11.1 (Dolphin Imaging and Management Solutions, Los Angeles, CA, USA), which calculated all reported measurements. Each subject was assigned a random identification number, and the examiner was blinded to the subject when measuring. The difference between the two experimental times in all groups was evaluated using the Student’s t-test for dependent variables. The difference between the two evaluation times in each group for all the variables was used to perform a one-way ANOVA test between the three groups. Results: No statistically significant difference was noted, apart from the angle between the upper incisor and the SN and PP planes, which showed an average decrease of 3.25 and 2.55, respectively, and the angle between the lower incisors and the mandibular plane, which showed an average increase of 2.85 degrees. The one-way ANOVA showed no statistically significant difference between the three groups. Conclusions: It appears that the leaf expander and the RME present similar effects such as dental and skeletal changes.

The aim of this paper is to analyse different variables which describe the size of mandibular and maxillary bases related to the different types of malocclusions. The study sample consisted of 218 adolescent orthodontic patients, mean age 15.8 years and all the measurements were done on the lateral cephalometric films taken at the beginning of the orthodontic treatment. The orthodontic diagnostic of Angle class malocclusion was established after orthodontic file examination. For all the patients were measured the maxillary length, the total length of the mandible, the length of the horizontal ramus, the angle between the cranial base planum and the mandibular plane and the gonial angle. All these values were represented according to Angle class type of malocclusion. The results showed that the sizes of the maxillary and mandibular bases are in a relative relation to the type of malocclusion, but they are not determinant for the aetiology and for the diagnostic of the malocclusion; in many cases the malocclusion is more dentally expressed or is due to the position of the jaws in sagittal and vertical plane.

IntroductionThe hyoid bone is deeply involved in three important body functions: deglutition, phonation and respiration. Several studies have shown that changes in the position of the hyoid bone may influence in pharyngeal size with mandibular advancement, thus a forward positioned hyoid bone may be an indicator of wide upper airways.ObjectiveTo determine the changes in the position of the hyoid bone after functional appliance treatment.Subjects and methods20 children (aged 9-13) that currently visit Hiroshima University Hospital actively undergoing FKO activator therapy volunteered for this study. Several lateral cephalometric radiographs were indicated and traced to assess hyoid bone position changes that might have occurred when actively complying with the FKO therapy, said radiographs were procured before active functional treatment (T0), during it (T1), and a year after continuous use of this appliance (T2). ANOVA tests were done to find statistical significance.ResultsThe results of these tests were analyzed and compared; it was found that, the hyoid bone is at a lower position from the mandibular plane and Frankfurt horizontal plane after FKO treatment, also the mandible is more forward after activator therapy, bringing the hyoid bone forward with it thus widening the lowest section of the upper airways.ConclusionThe FKO not only induces the proper development of the mandible, it also potentially advances the position of the hyoid bone, thus affecting positively in the opening of airways providing an improvement in the children’s breathing functions.Authors report no conflict of interest.FundingThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.Conflicts of interest/Competing intereststhe authors have no conflicts of interest to declare.Ethics approvalThis research has been approved by the Ethics Review Committee of Hiroshima University (No. E – 56).Consent to participateAll subjects needed to have provided informed consent from the parent or guardian prior all evaluations. This study has followed the guidelines stated in the Helsinki Declaration for clinical investigations.Consent for publicationAll subjects have provided informed consent from the parent or guardian to allow publication of acquired data.

Objectives To test the hypotheses that mechanobehavior scores (MBS) were correlated with mandibular ramus lengths (Co-Go) and differed between facial phenotypes. Materials and Methods Subjects gave informed consent to participate. Co-Go (mm), mandibular plane angles (SN-GoGn, °), and three-dimensional anatomy were derived from cephalometric radiography or cone beam computed tomography. Temporomandibular joint (TMJ) energy densities (ED) (mJ/mm3) were measured using dynamic stereometry and duty factors (DF) (%) were measured from electromyography, to calculate MBS (= ED2 × DF,) for each TMJ. Polynomial regressions, K-means cluster analysis, and analysis of variance (ANOVA) with Tukey post-hoc tests were employed. Results Fifty females and 23 males produced replete data. Polynomial regressions showed MBS were correlated with Co-Go (females, R2 = 0.57; males, R2 = 0.81). Cluster analysis identified three groups (P < .001). Dolichofacial subjects, with shorter normalized Co-Go, clustered into two subgroups with low and high MBS compared to brachyfacial subjects with longer Co-Go. SN-GoGn was significantly larger (P < .03) in the dolichofacial subgroups combined (33.0 ± 5.9°) compared to the brachyfacial group (29.8 ± 5.5°). Conclusions MBS correlated with Co-Go within sexes and differed significantly between brachyfacial and dolichofacial subjects.

Keywords: The aim of this study was to evaluate the effectiveness of denture frame analysis (DFA) in individuals with anterior open bite who had completed pubertal peak growth (post-peak).Methods: This retrospective study was conducted using the cephalometric radiographs and hand-wrist X-rays of 50 individuals with open bite (mean age: 17.33 +/- 3 years; 35 female, 15 male) and a control group of 50 individuals without open bite (mean age: 17.38 +/- 2.72; 35 female, 15 male). All individuals included in the study were skeletal Class I and had completed or nearly completed skeletal growth. Skeletal and dental measurements pertaining to DFA were done and the data were analyzed using independent samples t test and Mann-Whitney U test.Results: Measurements assessing the vertical dimension showed that GoGn/SN, Frankfurt horizontal (FH)/mandibular plane (MP), palatal plane (PP)/MP, occlusal plane (OP)/MP, and OP-MP/PP-MP measurements were significantly greater in the open bite group (p

Anatomical data of accessory mental foramina (AMFs) were investigated in a Chinese Han population using cone beam CT (CBCT). A retrospective analysis was performed on 527 selected sets of CBCT images. The average frequency and diameter of AMFs, the diameter of the ipsilateral mental foramen (MF), and the center distance and relative position between the AMFs and MF were measured and calculated by three professional dentists. Among the 527 patients, AMFs were identified in 36 cases (frequency 6.83%), of which 68.75% of AMFs were larger than 1 mm. The mean diameters of the AMFs and the ipsilateral MF were 1.32±0.61 mm and 3.26±0.90 mm, respectively. The average distance from the AMFs to the alveolar ridge crest (ARC) was 15.05±3.50 mm, and the average distance to the mandibular plane was 15.87±3.64 mm. The positions of the AMFs relative to the MF varied widely. The AMFs were mostly positioned distal-inferior to the ipsilateral MF and under the mandibular second premolars. Nutrient foramina around the MFs were distinguished from AMFs. The reference plane for measuring AMFs was suggested to be the mandibular plane to increase the repeatability and accuracy of the experiment. Standard planes were proposed to determine the relative position between AMFs and the MFs. Based on our results, we propose that for implant surgeries, the safety region of 2 mm above the MFs should be reevaluated. CBCT examination is recommended before the operation to identify important anatomical structures around the MF region and their variations and set the safety distance on an individual basis.

Introduction The knowledge of the nature and magnitude of growth and development of human face is important for sound diagnosis and treatment of dentofacial disharmonies. The depth of antegonial notch and morphology of mandible are important indicators of growth pattern. Objective The purpose of this study was to evaluate the antegonial notch depth, mandibular symphysis morphology, and symphysis inclination in various facial types categorized into the normo-, hypo-, and hyperdivergent groups using various parameters. Materials and Methods Pretreatment lateral cephalograms of 45 adult patients with age group between 16 and 30 years were taken. The antegonial notch depth, symphysis height, symphysis depth, ratio (height of symphysis/depth of symphysis), angulation of symphysis, and inclination of symphysis to mandibular plane were analyzed statistically. Result It was found that the mandible with the hyperdivergent growth pattern was associated with an increased antegonial notch depth, increased symphysis height, reduced symphysis depth, large ratio, small symphysis angle, and large inclination angle of the symphysis. Conclusion The results for the antegonial notch depth, symphysis height, symphysis depth, and ratio of symphysis height to symphysis depth were statistically significant whereas the angulation of the symphysis and inclination of the symphysis did not show statistically significant results.

Objectives: To identify differences in skeletal, dental, and soft-tissue morphology between postorthodontic patients with attractive and unattractive frontal posed smiles. Materials and Methods: The attractiveness of close-up photographs of frontal posed smiles in 100 adult female patients after conventional orthodontic treatment was evaluated by 20 dental students (10 men, 10 women) using a visual analogue scale. Posttreatment cephalograms of the 20 patients with the most attractive smiles (attractive group; mean age 23.75 ± 3.35 years) and the 20 patients with least attractive smiles (unattractive group; mean age 23.11 ± 4.45 years) were selected, and 41 measurements were made and compared between groups using the Mann-Whitney U-test (P < .05). Results: When compared with the attractive group, the unattractive group exhibited greater values for sella-nasion plane to mandibular plane, palatal plane to mandibular plane, anterior facial height, lower facial height, and lower facial height/anterior facial height as skeletal measurements; for occlusal plane to sella-nasion plane, palatal plane to occlusal plane, and maxillary central incisor to palatal plane as dental measurements; and for lower face, upper lip length, and upper lip superior to palatal plane as soft-tissue measurements. Conclusions: Cephalometric analysis revealed that postorthodontic Japanese female patients with unattractive frontal posed smiles are characterized by a hyperdivergent skeletal pattern with extruded maxillary incisors and a steep occlusal plane, accompanied by a longer upper lip than patients achieving attractive posed frontal smiles.

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

Introduction Elongated styloid process syndrome represents a group of symptoms, such as recurrent throat pain and neck pain, caused by elongation of the styloid process. We report a case of elongated styloid process syndrome with prolongation of the superior cornu of the thyroid cartilage. Case presentation A 50-year-old man was referred to our clinic with the chief complaint of discomfort on the right side of his neck. He had no history of any disease. Extraoral findings indicated pain during neck rotation. Computed tomography showed prolongation of the styloid process beyond the mandibular plane and close to the hyoid. Moreover, prolongation of the superior cornu of the thyroid cartilage was detected. The discomfort during rotation of the neck was due to the stimulation by the styloid process. Styloid resection was performed using the extraoral approach under general anesthesia. Conclusion Discomfort in the neck was resolved after operation., Highlights • Elongated styloid process syndrome represents a group of symptoms. • Morphological anomalies or deviations of the thyroid cartilage may cause swallowing discomfort. • Oral and extraoral methods are used as surgical techniques for styloid hyperplasia. • There have been no reports of styloid process prolongation with hypertrophic thyroid cartilage. • There are few reports concerning the prolongation of the superior cornu of the thyroid cartilage.

Introduction The present study involved an assessment of the effects of the Herbst appliance used for Class II correction in subjects with different vertical facial patterns. Methods Pre- and post-treatment lateral cephalograms of 91 growing Class II patients were divided into three vertical facial groups on the basis of mandibular plane angulation. All received a Herbst appliance and dental and skeletal changes were assessed in relation to pretreatment incisal overbite, overjet and the stage of cervical maturity. Results Herbst appliance treatment was accompanied by changes in the angulation of the upper and lower incisors, overjet reduction and an increase in mandibular length. In general, the rotational facial changes occurring during treatment were minimal, so that dolichofacial patterns remained long and brachyfacial patterns remained short. Conclusion Herbst appliance treatment can be expected to result in considerable Class II dental correction. It is unlikely, however, that its use will be associated with clinically significant forward rotation in dolichofacial subjects. Since dolichofacial patterns are likely to remain long-faced, even after considerable Class II dental correction, orthognathic surgery may still be a consideration if normal facial proportions, without excessive facial convexity and lip strain, are treatment aims.

Introduction The aim of this study was to evaluate the short- and long-term effects of hybrid-Hyrax, Alt-RAMEC and applied, miniscrew reinforced, heavy intermaxillary elastics on a modified lingual arch in growing skeletal Class III patients. Methods Fifteen subjects (seven male, eight female) were included, with an average age of 12.52 ± 0.94 years, of cervical vertebrae maturation (CVM) stage CS2-CS4 and skeletal Class III malocclusions due to a retrognathic maxilla. Nine weeks of Alt-RAMEC were followed by eight to nine weeks of maxillary protraction with heavy 400 gm Class III elastics worn 24 h/day. Treatment was finalised with orthodontic fixed appliances. Cone beam computed tomographic (CBCT) scans were taken initially (T1), at the end of maxillary protraction (T2) and four years after active orthopaedic treatment (T3). Cephalometric measurements were performed on reconstructed lateral cephalograms and the differences between time intervals were calculated using an analysis of variance (ANOVA). Results A positive overjet was achieved in all but one subject. From T1 to T2, A point advanced 3.12 ± 3.42 mm and from T2 to T3 advanced a further 2.21 ± 3.49 mm. Significant initial increases in SNA of 1.05° ± 1.10° (p = 0.004), ANB of 2.71° ± 1.01° (p = 0.00), Wits of 4.49 ± 2.21 mm (p = 0.00) and overjet of 4.90 ± 1.66 mm (p = 0.00) were accomplished and maintained without significant changes in the vertical dimension. Upper and lower incisor inclinations were not affected by the protraction protocol but significantly increased (U1-PP: 8.39° ± 5.59°) between T2 and T3. SNB decreased initially by 1.67° ± 1.34° (p = 0.00) but relapsed due to residual mandibular growth and a counterclockwise rotation of the mandibular plane. Conclusion The hybrid-Hyrax Alt-RAMEC combined with miniscrew reinforced heavy Class III elastics resulted in a favourable and stable Class III correction.

Introduction: the aim of this study was to evaluate the sagittal inclination of implants with respect to the occlusal plane of mandibular overdentures and their effect on the prosthetic behavior of the overdentures. Methods: 52 implants were evaluated in 26 fully mandible edentulous adults (two interforaminal implants per patient), rehabilitated with ball attachments and overdenture. Cephalometric tracing was conducted, evaluating the sagittal inclination of the implant to mandibular plane (MI), occlusal plane (OI), compensation angle (CA), and anterior facial height. The following clinical variables of prosthetic behavior were assessed: the need for prosthesis rebasing, changes in prosthetic accessories, and loosening of the prosthetic attachment. The variables were described with measurements of central tendency and dispersion. Intragroup comparisons were made with the Student’s t test (p < 0.05) and correlations with the Pearson coefficient. Results: 26 patients were evaluated: 70.4% females and 29.6% males. The average age was 67.93 ± 8.6 years. The follow-up period ranged from 24 to 30 months. The average MI was 78.89 ± 10.9 degrees. There was a statistically significant correlation (r = 0.6) between MI and OI in patients who underwent a change in accessories and between MI and bone loss (r = 0.557) (p = 0.007). The average MI was higher in patients subjected to rebasing (89.70 ± 11.7 degrees), compared with those who were not subjected to rebasing (76.91 ± 9.8 degrees). A relationship with prosthetic pillar loosening could not be determined. Conclusions: the sagittal inclination of implants with respect to the occlusal plane in overdentures affects bone loss, leading to a change of accessories as well as prosthesis rebasing after two years of service.

Background A key factor in planning orthodontic treatment is the position of the lower incisor, which must keep a correct relationship with its underlying bony support, the mandibular symphysis. Objectives To determine whether there is a statistically significant relationship among the position of the lower incisor, Holdaway ratio, symphyseal morphology, and facial pattern. Methods A total of 100 patients were randomly selected from the records of the Master in Orthodontics and Dentofacial Orthopedics (University of Seville, Spain). Measurements were made manually on pretreatment cephalograms by two operators using Aki analysis to assess the height/width ratio (H/A), mandibular plane with point B–Menton, and the retro-occlusion of the Jarabak/MSE analysis to determine the facial biotype. A descriptive analysis of the data was made evaluating the possible correlations between the Holdaway ratio and H/A, and the Holdaway ratio and mandibular angle. Results The correlation among facial pattern, H/A, and the Holdaway ratio proved significant ( P Conclusions Symphyseal morphology is correlated to facial growth pattern and lower incisal inclination. There are biological limits to inclination movements of the lower incisor in narrow symphysis, which are usually found in vertical growth patterns.