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Patients with skeletal Class Ⅱ often show symptoms such as protrusion of maxillary anterior teeth, mandibular retraction, open lips and teeth, deep overbite, and deep overjet, which seriously affect the facial appearance. This article reports a case of an adolescent male patient with skeletal Class Ⅱ combined with impacted teeth treated by one-stage early correction and two-stage fixation. After treatment, the patient’s skeletal Class Ⅱ symptoms improved significantly, including the improvement of mandibular retraction. The problem of open lips and teeth was solved; the facial appearance tended to be straight, and there was no obvious abnormality of the temporomandibular joint. This case shows that early correction can achieve good therapeutic effects on this kind of patients and can avoid or reduce the possibility of orthognathic surgery for these patients in adulthood.

Objective To explore the relationships among pharyngeal airway morphology, craniocervical posture, and anterior teeth position in hyperdivergent skeletal Class Ⅱ female adults and provide a reference for orthodontic clinical diagnosis and treatment. Methods Lateral cephalometric radiographs of 104 untreated skeletal Class Ⅱ (ANB ≥ 4.7°) female adults were included and divided into a hyperdivergent group (MP-SN ˃ 37°) (n = 52) and a normodivergent group (29° ≤ MP-SN ≤ 37°) (n = 52) by mandibular plane angle. The pharyngeal airway sagittal size, craniocervical angulation and anterior teeth position of the two groups were measured. Results Compared to the normodivergent group, hyperdivergent subjects exhibited narrower nasopharyngeal, velopharyngeal, and glossopharyngeal airways (P

Objective To evaluate the vertical distance between the maxillary first molars (MFMs) and the maxillary sinus floor (MSF) and its interrelationship with sex, age, and vertical facial pattern in skeletal ClassⅡ patients to provide a reference for clinical orthodontic treatment. Methods Sixty teenagers and sixty adults with skeletal Class Ⅱ malocclusion who met the inclusion criteria were selected to evaluate the vertical relationship between the MFMs and the MSF on cone-beam CT (CBCT) images. The vertical distance between the roots of the MFMs and the MSF was measured. Statistical analysis was used to assess differences between patients by sex, age, and vertical facial pattern. Results The contact percent of the roots of MFMs and MSF was 85% and 56% in skeletal Class Ⅱ teenagers and adults, respectively. The contact percent and penetration percent of the roots with MSF were higher in teenagers than in adults（P0.05); No significant difference was found between different sexes of skeletal Class Ⅱ patients when comparing the distance of the MFMs and the MSF (P>0.05). The MFMs of skeletal Class Ⅱ teenagers were closer to the MSF than those of adults (P0.05). In the teenager group, the MFMs were more closely related to the MSF in the NA and HA groups than in the LA group. Among them, the difference between the mesiobuccal roots and distalbuccal roots was significantly different (P0.05). Conclusion The MFMs were closer to the MSF in skeletal Class Ⅱ teenagers than in adults. The distance between the MFMs and MSF was associated with the vertical facial pattern in skeletal Class Ⅱ teenagers, while it was not associated with the vertical facial pattern in adult patients.

Objective To compare the hyoid bone position among patients with different sagittal skeletal malocclusions to provide a reference for clinicians to formulate treatment plans. Methods Lateral cephalograms of 284 orthodontic patients were selected. According to ANB angles, the types of skeletal malocclusion of patients were determined as follows: Class Ⅰ (1° ≤ ANB ≤ 5°), Class Ⅱ (ANB>5°) and Class Ⅲ (ANB0.05). The angle between the Gonion-hyoid point line and the hyoid point-Menton line (Go-Hy-Me) of Class Ⅱ patients was significantly smaller than that of Class Ⅰ patients, and the angle between the most anterior and inferior point of the third cervical vertebra-hyoid point line and the hyoid point-Sella line (C3-Hy-S) of Class Ⅲ patients was smaller than that of Class I patients (P0.05). Conclusions Compared with Class Ⅰ patients, the hyoid bone of Class Ⅱ patients in adult females was farther away from the mandible and that of Class Ⅲ patients in juveniles was farther away from the cervical vertebra and posterior cranial base.

Objective: To investigate the hard and soft tissue changing trend and contributing factors of skeletal class Ⅱ hyperdivergent patients before and after orthodontic camouflage treatment by analyzing the cephalogram and the three dimensional (3D) facial scan data., Methods: Eighteen skeletal class Ⅱ hyperdivergent adult female patients who finished camouflage orthodontic treatment were selected. Skeletal and dental measurements were carried out with the cephalometric analysis before and after the treatment. 3D facial data before and after orthodontic treatment were acquired and the anatomical landmarks were set after the repositioning and superimposition process. Hard tissue measurement included 17 mea-surement indicators (sella-nasion-subspinale angle, sella-nasion-supramental angle, subspinale-nasion-supramental angle, facial angle, angle of convexity, Frankfort horizontal plane-mandibular plane angle (FH-MP), Y axis angle, sella-nasion plane-mandibular plane angle (MP-SN), pogonion-nasion-supramental distance, upper incisor-nasion-subspinale distance, upper incisor to sella-nasion, lower incisor-nasion-supramental distance, lower incisor-nasion-supramental angle, upper incisor to lower incisor, upper incisor to sella-nasion, lower incisor-mandibular plane angle, and Z angle), and the changes before and after treatment were measured for 11 of them. Twenty soft tissue landmarks (left/right cheekbone, left/right chelion, left/right crista philtra, soft tissue gnathion, left/right gonion, glabella, labrale infe-rius, labrale superius, soft tissue menton, left/right mid-mandibular border, soft tissue pogonion, stomion superius, sublabial, subnasale, and supralabial) and 9 soft tissue indicators (lower lip height, facial convexity, lower vermilion height, mandibular contour, nasolabial angle, philtral length, philtral width, upper lip height, and upper vermilion height) were measured and recorded for treatment changes. Linear-regression analysis and correlation analysis were carried out for analyzing the relationship between hard and soft tissue changes before and after the treatment., Results: Significant differences were noticed for 18 out of the 20 cephalometric measurements and facial measurements before and after the treatment ( P < 0.05), which mainly represented the sagittal retraction of lip area after the treatment. Significant vertical displacements were revealed for soft tissue menton after treatment [(1.88±2.61) mm, P < 0.05]. Significant sagittal displacements were revealed for left/right cheilion [(-2.95±1.9) mm, (-2.90±1.92) mm], labrale inferius[(-4.94±1.95) mm], labrale superius[(-3.25±1.44) mm], sublabial [(-3.10±3.5) mm], and subnasale [(-1.23±1.06) mm] after treatment ( P < 0.05). An average of 4.10°±2.57° increasement was noticed for Z angle after treatment. High correlation ( r >0.7) was noticed for the displacement of menton after treatment with FH-MP, with the rate of -0.183 :1, and MP-SN, with the rate of -0.157 :1. Moderate correlations (0.7≥ r >0.4) were noticed for the other measurements with correlations ( P < 0.05)., Conclusion: A certain extent of facial improvements could be achieved with orthodontic camouflage treatment for skeletal class Ⅱ hyperdivergent patients, which were mostly represented by the improvement of sagittal relationship of nose, lips, and chin. Certain correlations were noticed for the hard and soft tissue changes.

Objective To investigate the differences in the condylar position of subjects with skeletal class I and skeletal class II . To provide a basis of diagnosis and treatment. Methods Group A was composed of 50 subjects with skeletal class I (27 males and 26 females; age range=18 years to 30 years; mean age=26 years). Group B comprised 50 subjects with skeletal class II (24 males and 26 females; age range=18 years to 28 years; mean age=25 years). The condylar position and the shapes of the condyle and the glenoid fossa were linearly measured on the sagittal and coronal sections by cone-beam computed tomography (CBCT). Data were analyzed by SPSS 19.0. Results No statistically significant differences were found in the measurements of the condylar position between the sides of each group on the sagittal plane and the coronal plane (P>0.05). There were significant differences on the anterior space and the posterior space between group A and B (P<0.05). The A/P joint space ratio of group A was larger than that of group B (P<0.05). Conclusion The subjects of skeletal class I show an anterior condyle position. The subjects of skeletal class II show a posterior condyle position. [ABSTRACT FROM AUTHOR]

Objective: To compare temporomandibular joint (TMJ) morphology and position among skeletal class Ⅱ female adolescents with different vertical patterns using cone-beam CT (CBCT)., Methods: Diagnostic CBCT images of 80 female patients aged 11 to 14 years were assessed retrospectively. According to subspinale-nasion-supramental angle (ANB) and Frankfort horizontal plane-gonion-gnathion angle (FH-GoGn), the participants were categorized into four groups (20 subjects each), i.e. class Ⅰ normal angle (group 1, 0°≤ANB < 4°, 22°≤FH-GoGn≤32°), class Ⅱ low (group 2, ANB≥4°, FH-GoGn < 22°), normal (group 3, ANB≥4°, 22°≤FH-GoGn≤32°) and high angle (group 4, ANB≥4°, FH-GoGn > 32°). Cephalometrics, morphology and position of TMJ were measured in Dolphin software. Using paired-samples t test to analyze TMJ symmetry, One-way analysis of variance (One-way ANOVA) and Chi-square tests to detect differences among the groups. The correlations between cephalometrics and TMJ measurements were also analysed within the skeletal class Ⅱ patients., Results: (1) Analysing TMJ morphologic symmetry, some measurements differed statistically although the mean diffe-rences were negligibly relative to their values. No statistically significant difference was found among the groups though group 4 showed the highest probability of condylar position asymmetry (65%). (2) Comparing group 1 with group 3, statistical difference was found in condylar position ( χ 2 =6.936, P < 0.05) instead of morphologic measurements. Anterior and concentric condylar position were more frequently observed in group 1, yet posterior position was more prevalent in group 3. (3) In groups 2, 3, and 4, statistically, group 2 had the deepest glenoid fossa depth ( H 2&4 =10.517, P =0.002), biggest superior (LSD- t 2&3 =3.408, LSD- t 2&4 =5.369, P < 0.001) and lateral (LSD- t 2&3 =2.767, LSD- t 2&4 =3.350, P =0.001) joint spaces, whereas group 4 showed the shortest condylar long axis diameter ( H 2&4 =13.374, P < 0.001), largest glenoid fossa vertical distance (LSD- t 2&4 =4.561, P < 0.001, LSD- t 3&4 =2.713, P =0.007), smallest medial (LSD- t 2&4 =-4.083, P < 0.001) and middle (LSD- t 2&4 =-4.201, P < 0.001) joint spaces. The posterior condylar position proportion gradually increased from groups 2 to 3 to 4. Correlation analysis revealed ANB correlated with anterior joint space positively ( r =0.270, P =0.037) and condylar long axis angle negatively ( r =-0.296, P =0.022). FH-GoGn correlated with superior ( r =-0.488, P < 0.001), posterior ( r = -0.272, P =0.035), mesial ( r =-0.390, P =0.002), middle ( r =-0.425, P =0.001), and lateral ( r =-0.331, P =0.010) joint spaces, articular eminence inclination ( r =-0.259, P =0.046), as well as condylar long axis diameter ( r =-0.327, P =0.011) negatively, and glenoid fossa depth ( r =0.370, P =0.004) positively., Conclusion: TMJ characteristics of skeletal class Ⅱ sagittal pattern mainly reflected in condylar position rather than morphology. TMJs of different vertical patterns differed more in joint spaces, position of condyle and glenoid fossa than in morphologic measurements. Vertical position of glenoid fossa and proportion of posterior condyle increased gradually from hypodivergent to hyperdivergent. Highest glenoid fossa position, maximum ratio of posterior positioned condyle, smallest joint spaces, shallowest glenoid fossa depth, and narrowest condylar long axis diameter were found in skeletal class Ⅱ high angle group, which means that patients with this facial type have considerable joint instable factors, and we should especially pay attention when orthodontic treatment is carried out on them.