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Objective@#To explore the ideal sagittal position of the lower third of the face in high-angle patients with different forehead forms and to provide a reference for clinical treatment. @*Methods@#Informed consent and portrait authorization were obtained from all patients, and the study passed the ethical review of the unit. We categorized forehead forms into four types: straight, rounded, type I angular (angled at the middle third of the forehead) and type II angular (angled at the upper third of the forehead). Profiles of high-angle patients with different forehead forms were collected. The initial position was when the facial axis point (FA point) was positioned at the goal anterior-limit line (GALL). After being silhouetted, the lower third of the face was moved forward and backward by 1 mm, 2 mm, 3 mm, and 4 mm each, plus the initial silhouetted picture, to obtain 9 images for each patient. A survey was created with these lateral profile silhouettes, and the silhouette images were ranked by 30 orthodontists and 30 laypersons. @*Results@# There were significant differences in profile scores at different movement distances of the lower third of the face among high-angle patients with different forehead shapes (P<0.05). Overall, high-angle patients with straight or type II angular foreheads had higher scores when the lower third of the face did not move. For high-angle patients with a rounded forehead, orthodontists and laypersons gave the highest scores when the lower third of the face was moved backward by 2 mm and 4 mm, respectively. For high-angle patients with a type I angular forehead, orthodontists thought the scores of backward movement of 4 mm were the highest, and laypersons thought the scores of backward movement of 3 mm were the highest. No significant difference was found in scores between orthodontists and laypersons (P>0.05). @*Conclusion @#The forehead forms and the sagittal position of the lower third of the face will affect the face’s profile aesthetics. Patients with straight and type Ⅱ angular foreheads has the best profile when the FA point is located on the GALL line. For patients with rounded and type Ⅰ angular foreheads, a posterior location of the lower third of the face is more desirable than the initial position.
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Objective@#To investigate the features of alveolar bone morphology of mandibular central incisors in high-angle adult females using cone-beam computed tomography (CBCT) and evaluate the influence of aging in these patients.@*Methods@# CBCT and lateral cephalometric images of 142 untreated adult female patients were selected and grouped by facial growth pattern. The number of high-angle cases was increased to 164 to further explore the difference within high-angle adult females who were divided into two groups according to age. The indexes of alveolar bone height and thickness in the lower incisor region and inclination of the lower incisors were measured by Dolphin software. The data was statistically analyzed.@*Results@#Compared with the average-angle group, the high-angle group had a lower alveolar bone attachment level (P < 0.05) and less bone thickness at the root apex level (P < 0.05). The thickness of lingual alveolar bone decreased with labial inclination of the lower incisors in both the high-angle and average-angle groups (r = -0.251, P = 0.025; r = -0.428, P = 0.001, respectively). In hyperdivergent female patients, the middle-aged group had a lower attachment level of alveolar bone than the young group (P < 0.05), but no significant difference in bone thickness at the root apex level (P > 0.05) was found between the two groups@*Conclusion @# High-angle adult females had thinner mandibular anterior alveolar bone with significantly lower attachment levels. Aging and inclination of lower incisors influenced bone morphology and should be taken into careful consideration.
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Objective:To analyze the differents in the upper airway morphology and hyoid position between skeletal class III malocclusion of high-angle and normal occlusion by cone beam CT(CBCT), and to study the influence of skeletal class III malocclusion of high-angle in the upper airway and hyoid position of the adults preliminarily.Methods:A total of 42 adults in Department of Orthodontics, Dalian Stomatology Hospital were chosen, including 21 adults with skeletal class III malocclusion of high-angle and 21 adults with normal occlusion. MIMICS 20.0 software was used to measure the line spacing, cross-sectional area and volume of each upper airway segment and line distance of hyoid of the patients on CBCT; SPSS 20.0 software was used for statistical analysis.Results:Compared with normal occlusion group, the maximum lateral distance (LAT1) of the nasopharynx, the maximum anterior-posterior distance (AP2) of the velopharyngeal, and the volume of the velopharyngeal (VOL2) of the patients in skeletal class III malocclusion of high-angle group were increased (P0.05)Conclusion:Cross-sectional area and volume of velopharyngeal have the tendency of increase, but cross-sectional area and volume of laryngopharynx have the tendency of decrease in the patients with skeletal class ? malocclusion of high-angle. The hyoid bone has a tendency to shift forward and upward in the patients with skeletal class ? malocclusion of high-angle.
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Objective @#To measure and compare condyle-related indexes(volume, surface area, anterior space, upper space and posterior space) in adult female patients with different sagittal malocclusions with the aim of providing a reference for clinical treatment. @*Methods @#The CBCT database of Qingdao Stomatology Hospital was searched to identify patients with high-angle adult skeletal malformations with the following classifications: classⅠ(n=30), class Ⅱ(n=30), and class Ⅲ(n=30). The CBCT images associated with the sample population were stored according to DICOM3.0 medical digital image communication standards. Mimics10.01 software was used to read and prepare three-dimensional reconstructions of the condylar, and the above-listed indicators were measured and statistically analyzed. @*Results @# There were no significant differences between the right and left sides among the three groups (P > 0.05). For parameters including condylar anterior joint space and post-joint space, the differences among the three groups were significant (P < 0.05). There was no significant difference in parameters related to condylar articular space between classⅠand class Ⅱ(P > 0.05). The differences between skeletal classesⅠand Ⅲ and between skeletal ClassesⅡ, and Ⅲ were statistically significant (P < 0.05). @*Conclusion@#Condylar position varies among high-angle adult woman with skeletal malocclusions with different sagittal skeletal patterns.
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Objective@# To investigate the relationship between the morphology of the oropharyngeal airway and the maxillofacial skeletal morphology by comparing the three-dimensional morphology of the oropharyngeal airway in different sagittal features of the high angle adult. @*Methods@#60 high angle adults aged 18 to 36 years were divided into 3 groups based on their ANB angles, there were 20 adults in each group, the number of males were equal to females. The In vivo Dental 5.1 software for reconstructing the CBCT image of each one was used, the middle sagittal plane and axial plane in coronal, sagittal and axis view was adjusted, then the distances, volumes and minimum cross-sectional areas were measured. The differences among 3 groups and between different gender were compared.@*Results @#There was statistical difference in W-ETP among 3 groups (P< 0.05). There were statistical difference in H-GP、H-Total、W-PNSP、W-ETP、V-GP、V-Total (P< 0.05) between males and females, and these measurements of males were bigger than of females.@*Conclusion @#The difference of the size and shape of the oropharyngeal airway of high angle adults among different sagittal skeletal patterns was mainly reflected in the lowest width of glossopharyngeal airway, the oropharyngeal airway of males was bigger and longer than females.
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Objective @# To investigate the relationship between the morphology of oropharyngeal airway and craniofacial morphology in high angle patient by cone beam CT images.@*Methods@#CBCT images of 60 high-angle adult patients were randomly selected in the Affiliated Stomatological Hospital of Nanchang University. The line distances, volumes and min cross-sectional areas of each part of oropharyngeal airway were measured by the InvivoDental 5.1 software. Pearson correlations analysis of all measurements was performed on all the parameters of oropharyngeal airway and maxillofacial structures.@*Results @#In male group, SNB showed positive correction with UTL, PPV, GPV, OPV, MinS. Thereas the GoGn-SN angle showed negative correction with UTL, ETL, PPV, GPV, OPV, MinS, S-Go/N-Me was positive correlated with UTL. In female group, SNA showed negative correction with PNSW. The SNB angle showed negative correction with GPH、PNSW、UTW, GoGn-SN showed positive correction with GPH.@*Conclusions @#In high angle adults, the morphology of oropharyngeal airway exist some degrees of correlation with the maxillofacial structures. In male group, the dimension of the oropharyngeal airway tend to increase with the forward of mandible, and tend to decrease or obstruct with the clockwise rotation of mandible. In female group, with the changes of position of maxilla and mandible, oropharyngeal airway showed only partial morhological change.
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The patient with an anterior open bite has one of the most difficult orthodontic problem to correct Previous studies have yielded different conclusions as to exactly where the morphologic problems associated with vertical dysplasia- high angle cases are located. In order to identify the cephalometric features of high angle cases and highlight the measurements that characterize high angle cases, 109 pretreatment cephalograms, 35 high angle, 37 average angle, and 37 low angle cases, were analyzed and compared statistically. As the mandibular plane was steeper, the anterior facial height, especially lower anterior facial height, became greater, and the posterior facial height became smaller. All the dentoalveolar vertical dimensions, especially in upper, increased. Arid all the skeletal angular measurements increased. Especially Lower gonial angle had most positive correlation to mandibular plane angle. Upper incisor was lingually inclined, and lower incisor was labially inclined in high angle cases.
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Humans , Incisor , Open Bite , Vertical DimensionABSTRACT
The purpose this study was to investigate the variations of the soft tissue profile contour in relation to the skeletal patterns and to confirm the correlation of soft tissue angles to the sagittal or vertical skeletal elements. Lateral cephalograms of 79 cases which were older than 17 years in age, were traced and statistically analyzed. The obtained results were as follows : 1. Nasolabial angle, interlabial angle, lower lip angle, mentolabial angle, symphyseal angle showed the significant differences between skeletal Class II and skeletal. Class III group, but nasofrontal, upper lip, mentolavbial, and symphyseal angles showed the significant differences between high angle low angle group. 2. ANB value showed the dignificant positive correlation to nasolabial, symphuseal, and interlabial angles and the significant negative felation to lower lip angle. 3. SN-GoMe vlue showed the significant positive correlation to mentolabial, symphyseal, nasofrontal, and upper lip angles. 4. Soft tissue profile contour in SK. Class II group showed greater accofdance to SN-GoMe value than those in SK. Class III group.
Subject(s)
LipABSTRACT
Objective:To investigate the electromyography activities of the facial and neck muscles during mandibular movement in children with high-angle.Methods:A computer-integrated BioEMG Ⅱ diagnostic system was used to synchronously record the electromyography activities of temporal anterior(TA), masseter muscle(MM), sternocleidomastoid(SCM) and digastric anterior(DA) muscles during mandibular movement in 14 children with high-angle and 16 children with normal-angle.Results:Muscular activity of TA, DA and SCM in children with high-angle was significantly weaker than that in those with normal-angle in the rest position(P
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Objective: To specify what we should notice during the treatment of Class Ⅱ high-angle malocclusions.Methods: 14 patients(8 male and 6 female) with Class Ⅱ high-angle malocclusions were investigated with Tweed-Merrifield morphology analysis.Results: (1)FMIA and Z-angle were increased after treatment(P