上海地区216例青少年年龄与颈椎骨成熟度关系的研究

目的:探讨青少年年龄与颈椎骨成熟度间的相关性。方法:采用双盲法,对216例10～20岁青少年的X线头颅侧位定位片,采用SAS6.12统计软件分析C2～C5颈椎体生长发育的状态,与年龄间的相互关系以及性别间有无差异。结果:随着年龄增长,C2～C5颈椎骨形态呈规律性变化,女性比男性约提前2a,在11岁和12岁年龄段有统计学差异,但形态变化无性别差异。青春快速生长发育期的开始时间和高峰期时间,个体差异大。结论:用头颅侧位片观察颈椎骨的形态变化判断儿童的生长发育状态,比用年龄来判断快速生长期更为准确,是临床上简便可行的方法。     

Stature,head height,and growth of the vertical face

Six hundred sixty-three cephalometric radiographs are used in a mixed longitudinal sample of fifty-one subjects (twenty-six males and twenty-five females) in order to determine patterns of vertical facial change during growth and to discern lower, mid-, and upper facial relationships with stature and head height. Results indicate that the absolute growth of the face is similar to the neural pattern and that throughout growth the face is larger among males than among females. However, when facial values are examined relative to stature and head height, the vertical face changes at a rate that resembles statural growth. Moreover, when relative growth values are standardized in order to reduce scaling differences, they indicate that, although relative growth for all three facial measures falls between neural and skeletal values, it is closer to the postcranial pattern of change than to the neural pattern. In addition, relative size of the upper face is highly correlated with relative size of the lower face. It is concluded that stature is of greater importance than head height in the prediction of vertical facial growth.     

上海地区208名儿童颈椎骨成熟度的研究

初步建立上海地区儿童颈椎发育标准值，为正畸的临床诊断，治疗提供有效的评定骨龄的参考指标。方法通过对Ｘ线头颅侧位定片的测量，分析上海地区２０８名１１－１５岁儿童的Ｃ２－Ｃ５颈椎体生长发育的状态及其相互关系，观察颈椎发育的形态变化规律。结果 Ｃ２－Ｃ５颈椎骨前，后缘高度及面积随年龄增长逐步递增，颈椎形态呈规律性变化，女性比男性约早熟２年，但形态变化无性别差异。     

Childhood and pubertal growth changes of the human symphysis.

Longitudinal growth changes of the human symphysis were evaluated for 75 children (37 males and 38 females) between 6 and 15 years old. Childhood growth was described by mean yearly rates of change between 6 and 10 years for females and between 7 and 11 years for males; pubertal changes pertain to growth between 10 and 14 for females and between 11 and 15 for males. Cephalometric tracings of the mandible were superimposed using stable reference structures. Vertical growth changes, particularly for landmarks located in the upper 20% of the symphysis, were most pronounced. Annual rates of vertical growth ranged between 0.9 mm/yr for the lingual incisor contact point to -0.2 mm/yr for gnathion. Males showed significantly greater rates of vertical growth than females, especially for the upper half of the symphysis. Vertical growth rates were also greater during puberty than during childhood. The horizontal growth changes indicated lingual movement of most symphyseal landmarks. Annual rates of growth were greatest for landmarks located in the upper half of the symphysis. B-point showed the greatest lingual drift. During puberty, the mandibular incisors in females moved lingually as the upper anterior half of the symphysis remodeled; in males, the incisors maintained their horizontal position as the labial sulcus developed.     

Changes in mandibular growth direction during and after cervical headgear treatment.

Cervical headgear is widely used to modify sagittal growth in growing patients. However, cervical headgear can affect vertical growth as well. The purpose of this retrospective cephalometric study was to examine mandibular growth changes in 30 growing Class II patients treated with cervical headgear and full edgewise appliances and to compare those changes with the changes occurring in 26 untreated controls. Cephalometric data were obtained from lateral cephalometric radiographs representing pretreatment, posttreatment, and postretention for each patient and from chronologically comparable radiographs for the control subjects. During the 4-year treatment or observation period, the mean mandibular rotation was 0.25 degrees in the treatment group and -1.7 degrees in the control group. After an average posttreatment period of 6 years 5 months, the mandible had rotated -1.5 degrees in the treatment group and -0.7 degrees in the control group. Mean changes in the y-axis angle and the mandibular plane angle during retention were not different between the 2 groups. Mandibular rotation during retention did not show any significant inverse correlation with mandibular rotation during treatment. These findings suggest that mandibular rotation during retention reflects the inherent growth pattern of an individual that is reasserted after treatment, rather than rebound. There were no significant differences in the size of the mandible between the 2 groups during the study period. None of the variables reflecting pretreatment morphology of the face had a clinically significant bearing on mandibular rotation. Vertical changes in the maxillary and mandibular molars showed no significant correlation with mandibular rotation, which suggests that the changes in vertical dimension of the dentition are not a major determinant of the rotational change of the mandible.     

Changes in mandibular position and upper airway dimension by wearing cervical headgear during sleep.

We previously reported that the wearing of cervical headgear induced forward displacement of the mandible in awake subjects. However, it was unclear whether such mandibular displacement also occurred during sleep. The purpose of this study was to examine changes in mandibular position and oropharyngeal structures that were induced by the wearing of cervical headgear during sleep. Ten healthy adults (7 male and 3 female) who gave their informed consent were included in this study. A pair of lateral cephalograms was taken with the patient in the supine position with and without cervical headgear at end-expiration during stage 1 to 2 non-rapid-eye-movement sleep. The Wilcoxon signed-rank test was used for a statistical analysis. The amount of jaw opening was significantly decreased by the wearing of the cervical headgear (P <.05), although no significant anteroposterior mandibular displacement was induced. The sagittal dimension of the upper airway was significantly reduced (P <.05); however, no significant changes were observed in the vertical length of the upper airway. Although the hyoid bone and the third cervical vertebra moved significantly forward by the wearing of the cervical headgear (P <.05), the relationship among the mandibular symphysis, the hyoid bone, and the third cervical vertebra did not change. These results suggest that cervical headgear significantly reduced the sagittal dimension of the upper airway during sleep, although there was no significant anteroposterior displacement of the mandible.     

Mandibular remodeling after bilateral sagittal split osteotomy for prognathism of the mandible.

PURPOSE: To describe the postoperative remodeling changes in the mandible after bilateral sagittal split osteotomy to correct mandibular prognathism. PATIENTS AND METHODS: Twenty patients who underwent bilateral sagittal split osteotomy for the correction of mandibular prognathism were studied for postoperative remodeling changes within the mandible. The 6-week, 1-year, and long-term postoperative cephalometric mandibular tracings of 12 patients were superimposed using the fixation wires as the stable reference points to demonstrate the specific locations of the intrabony remodeling. RESULTS: There was a general direction of remodeling at the condylion and gonion anteriorly and superiorly, while the B point and pogonion did not show much change in remodeling. At the condylion, 60% and 40% of the cases showed significant horizontal and vertical remodeling, respectively. At the gonion, 50% and 55% of the cases showed significant horizontal and vertical remodeling, respectively. No correlation was found between the remodeling changes at condylion and gonion and the surgical movement or relapse at B point and pogonion. There was a significant correlation between the observed horizontal relapse at gonion and the horizontal remodeling changes at this point showing that the postoperative displacement of this point is a result of both positional translocation and remodeling changes. CONCLUSION: The results of this study show that there are intrabony remodeling changes that occur in the mandible after sagittal split osteotomy and that these continue for a long period of time in some patients. This remodeling occurred more in the condylar and gonial areas, while the chin remained relatively stable.     

Patterns of vertical growth in the face

The purpose of this study was to examine the patterns of facial growth development in subjects with skeletal open-bite and skeletal deep-bite faces. Longitudinal data based on lateral cephalometric radiographs of 16 male and 16 female subjects, ages 3 through 18 years, were used. These subjects were selected on the basis of lower face height as a percentage of total face height. Persons exhibiting extreme values were selected to create four groups with eight subjects in each group. Curves of absolute and incremental growth for total anterior face height, upper anterior face height, lower anterior face height, posterior face height, and ramal length were analyzed statistically and graphically. It was established that the anterior dimensions of the face demonstrated typologically divergent patterns of development in open- and deep-bite faces. Further, the posterior dimensions of the face did not discriminate between these two typological groups. The female open-bite subjects were earliest in the timing of the adolescent growth spurt, followed in succession by deep-bite female subjects, open-bite male subjects, and finally the deep-bite male subjects. The clinical implications of these observations pertain to the timing of orthodontic treatment, the length of retention period, and the prediction of adult occlusal status during the mixed dentition.     

Association between morphology of the first cervical vertebra, head posture, and craniofacial structures.

In order to test the assumption of an association between the anatomy of the first cervical vertebra, the atlas, and dentofacial build, roentgen-cephalograms of 78 young adults with either a markedly high or a low atlas dorsal arch were analysed with regard to head posture, and cervicovertebral and dentofacial anatomy. The high and low dorsal arch groups each comprised 22 women and 17 men. The head was more extended in the low arch groups and particularly so among the women, in whose low arch group there was a tendency for the cervical spine to be inclined more forward. Both the dorsal arch and the dens of the second vertebra were vertically smaller in the low arch groups, and more so among the men. Vertebral length was reduced more in the women, however. The clival plane was more parallel to the foraminal plane in the low arch groups and the gonial angle was more obtuse. Furthermore, the women with low arches showed a steepened mandibular plane, a backward-rotated condylar head, a decrease in the ratio of posterior to anterior face height, smaller vertical overbite and reduced proclination of the lower incisors. The prevalence of severe malocclusions was higher than in the corresponding high arch group.     

Ethnic differences in craniofacial and upper spine morphology in children with skeletal Class II malocclusion

Objectives:To analyze differences in upper cervical spine and craniofacial morphology, including posterior cranial fossa and growth prediction signs, between Danish and South Korean pre-orthodontic skeletal Class II children and to analyze associations between upper cervical spine morphology and craniofacial characteristics.Materials and Methods:One hundred forty-six skeletal Class II children—93 Danes (54 boys and 39 girls, mean age 12.2 years) and 53 Koreans (27 boys and 26 girls, mean age 10.8 years)—were included. Upper spine morphology, Atlas dimensions, and craniofacial morphology, including posterior cranial fossa and growth prediction signs, were assessed on lateral cephalograms. Differences and associations were analyzed by multiple linear and logistic regression analyses adjusted for age and gender.Results:Significant differences between the ethnic groups were found in the sagittal and vertical craniofacial dimensions (P < .001), mandibular shape (P < .01), dental relationship (P < .01), posterior cranial fossa (P < .05), and growth prediction signs (P < .001). No significant differences were found in upper spine morphology and Atlas dimensions between the groups. Upper spine morphology/dimensions were significantly associated with the cranial base angle (P < .01), sagittal craniofacial dimensions (P < .001), posterior cranial fossa (P < .001), and growth prediction signs (P < .05).Conclusions:Upper spine morphology/dimensions may be valuable as predictive factors in treatment planning for growing Class II children.     

Trunk asymmetry and facial symmetry in young adults

The aim of the present study was to detect possible associations between trunk and cervical asymmetry and facial symmetry. Frontal cephalograms prepared in the natural head position, representing 79 subjects (40 males, 39 females) with mild to moderate trunk asymmetry, were analyzed separately for thoracic humps, lumbar prominences, and cervical inclination by discriminating two groups: right-sided-dominant and left-sided-dominant. The differences between the groups were analyzed using an unpaired 2-group t test. The results showed that location of the thoracic humps and inclination of the cervical spine was predominantly right-sided, while the location of lumbar prominence was predominantly left-sided. Craniofacial morphological variables of the head and face were nearly equal for right-sided and left-sided thoracic humps and lumbar prominences, showing that moderate trunk asymmetry does not affect facial symmetry. Further, it was found that frontal head position in relation to the true vertical (VER/ORB) is stable in that the angle between the supraorbital and vertical lines is constantly maintained close to 90 degrees regardless of moderate trunk asymmetry, indicating that visual perception control is most important in orienting the head in frontal plane. Maintenance of the head position takes place by cervical spine adaptation.     

Trunk asymmetry and facial symmetry in young adults

The aim of the present study was to detect possible associations between trunk and cervical asymmetry and facial symmetry. Frontal cephalograms prepared in the natural head position, representing 79 subjects (40 males, 39 females) with mild to moderate trunk asymmetry, were analyzed separately for thoracic humps, lumbar prominences, and cervical inclination by discriminating two groups: right-sided-dominant and left-sided-dominant. The differences between the groups were analyzed using an unpaired 2-group t test. The results showed that location of the thoracic humps and inclination of the cervical spine was predominantly right-sided, while the location of lumbar prominence was predominantly left-sided. Craniofacial morphological variables of the head and face were nearly equal for right-sided and left-sided thoracic humps and lumbar prominences, showing that moderate trunk asymmetry does not affect facial symmetry. Further, it was found that frontal head position in relation to the true vertical (VER/ORB) is stable in that the angle between the supraorbital and vertical lines is constantly maintained close to 90 degrees regardless of moderate trunk asymmetry, indicating that visual perception control is most important in orienting the head in frontal plane. Maintenance of the head position takes place by cervical spine adaptation.     

Evaluation of the vertical holding appliance in treatment of high-angle patients

Controlling the vertical dimension of high-angle patients without the benefit of compliance can be a challenging aspect of orthodontic treatment. This retrospective study examines the skeletal and dental effects of a modified transpalatal bar, dubbed the vertical holding appliance (VHA), which was used in an attempt to control the vertical dimension of high-angle patients. Two cephalometrically similar groups of high-angle patients (16 patients each) were compared to determine advantages from using the VHA. Group I (n = 16, pretreatment age 13.4 +/- 1.6 years) was treated with 4 premolar extractions in conjunction with the VHA cemented in place for 17.4 +/- 6.1 months. Group II (n = 16, pretreatment age 13.4 +/- 1.9 years), which was matched for age and pretreatment skeletal pattern, was treated with the Tweed technique and 4 premolar extractions. Lateral cephalometric radiographs were taken before the placement of the VHA, as well as at the end of treatment. The results showed that although y-axis increased significantly in group II (P <.05), it remained the same in group I. Within group I, the Frankfort mandibular plane angle and gonion gnathion/sella nasion angle decreased, whereas both of these values increased in group II. However, these changes were statistically insignificant. Lower anterior face height increased more in group II than in group I (P <. 05). The percentage of lower anterior face height to total anterior face height decreased in group I, whereas it increased in group II. The difference between the 2 groups was determined to be significant (P <.01). Eruption of the maxillary first molar within group I was less than in group II. No significant differences were found between groups I and II for changes in overbite.     

A cephalometric study to compare the effects of cervical traction and Andresen therapy in the treatment of Class II division 1 malocclusion. Part 1--Skeletal changes

Lateral cephalometric radiographs at the beginning of treatment, end of active treatment, and post-treatment of 30 Andresen and 40 cervical traction patients were analysed, and compared with those of a control group of 22 untreated cases. The cervical traction group was divided into a non-extraction group and an extraction of maxillary second molars group. A clinically significant reduction of ANB was achieved, mainly by mandibular changes in the Andresen group and by maxillary changes in the cervical traction groups. Cervical traction was associated with a small distal positioning and anterior downward tipping of the maxilla during treatment. A more favourable sagittal position of the mandible was achieved in the Andresen group compared to the cervical traction groups, particularly the non-extraction group, where a greater transient backward rotation of the mandible occurred during treatment. A significant, but clinically small increase in mandibular body length occurred in Andresen patients compared to the control. However, in both treatment groups this was due to an increase in growth of the vertical ramus. The lower face heights, both anterior and posterior, increased in all groups, with the anterior upper face height also increasing in the cervical traction group.     

Long-term changes in hyoid bone position and craniocervical posture in complete denture wearers

Changes in hyoid position in relation to changes in mandibular inclination and craniocervical posture were studied by roentgen cephalometrics in a sample of 24 long-term complete denture wearers over a 15-year period. The measurements were made on lateral occlusion films obtained with the subjects in the sitting position and with the head oriented according to its natural balance. The changes in mandibular inclination ranged from -5.5 degrees to 8.6 degrees, with a mean of zero. The cervical column became significantly more forward inclined (mean, 5 degrees), and the craniocervical angulation became on an average 5 degrees larger. Correlation analyses indicated that the hyoid position was influenced by two postural systems: the changes in mandibular inclination and the changes in cervical and craniocervical posture. The vertical changes in hyoid position in relation to the upper face largely followed the patterns of increase or decrease in mandibular inclination, whereas the horizontal changes mainly followed the changes in cervical inclination and craniocervical angulation.     

生长发育期反(牙合)伴上颌严重拥挤不拔牙矫治16例报告

目的:探讨生长发育期反(牙合)伴上颌严重拥挤病例不拔牙矫治的临床疗效.方法:16例反(牙合)伴严重拥挤病例男6例,女10例,平均10.5岁.均采用直丝弓矫治器矫治,应用螺旋推簧扩展间隙及上颌前方牵引.平均疗程25个月.选择18项头影测量值,比较矫治前后软硬组织改变情况.结果:矫治后SNA、ANB、颌凸角均有显著增大,U1-SN减小,U1-L1显著增大,AB平面角显著减小,ANS-Me显著增大,FMA、GoGn-SN、Y轴角轻度增大,颏唇角显著减小,上唇突度显著增大,患者软组织侧貌得到明显改善.结论:对于生长发育期的反(牙合)伴上颌严重拥挤病例,矫治设计时应考虑患者的生长潜力,试行不拔牙矫治,使牙齿发育对颌骨发育的刺激作用得以充分表达,可以得到明显的临床效果.     

Impaired mandibular growth and micrognathic development in children with juvenile rheumatoid arthritis. A longitudinal study of lateral cephalographs.

The present report is a longitudinal study of the craniofacial growth, based on lateral cephalographs of a group of 26 patients with juvenile rheumatoid arthritis (JRA), and a matched English control group. In the 26 matched pairs, the mean age at baseline was 8.4 years and at 6-year follow-up 14.7 years, female/male ratio was 3.3/1, and all patients had temporomandibular joint (TMJ) abnormalities. The study revealed obvious growth disturbances in the facial skeleton in the children with JRA. Compared with the controls, the patients showed a smaller mandible with an altered morphology and position. The mandible became more retruded by rotating posteriorly, around a centre in the molar region, and was characterized by appositional growth in the gonion area, vertical growth in the anterior part and proclination of the lower incisors. During the observation period the growth disturbances became more pronounced, reflecting the progressive nature of the abnormal development. Based on these findings, a future aspect of research in this field could be TMJ surgery and orthognathic surgery in an early stage, trying to avoid this unfavourable facial development.     

Changes in the pharyngeal airway in relation to extension of the head

In a sample of 20 adults the associations between cervical lordosis, craniocervical inclination, position of the hyoid bone and cross-sectional dimensions of the pharyngeal airway were studied. Lateral skull radiographs were obtained in natural head posture and also at 20 degrees extension with the subjects' teeth in the intercuspal position. Cervical lordosis was measured from the second to the sixth vertebra and the position of the hyoid bone was calculated in horizontal and vertical directions. The dimensions of the free airway were measured between the dorsal tongue surface and the posterior pharyngeal wall and at the level of the second and fourth vertebra. A change from natural head posture to 20 degrees extension resulted in an increase in cervical lordosis and craniocervical inclination, changed position of the hyoid bone and increased cross-sectional dimensions of the pharyngeal airway. The changes in lordosis produced by changing natural head posture to 20 degrees extension showed significant correlations with the size of changed craniocervical inclination and free airway.     

Characterizing mandibular growth using three-dimensional imaging techniques and anatomic landmarks

ObjectiveTo provide quantitative data on the multi-planar growth of the mandible, this study derived accurate linear and angular mandible measurements using landmarks on three dimensional (3D) mandible models. This novel method was used to quantify 3D mandibular growth and characterize the emergence of sexual dimorphism.DesignCross-sectional and longitudinal imaging data were obtained from a retrospective computed tomography (CT) database for 51 typically developing individuals between the ages of one and nineteen years. The software Analyze was used to generate 104 3DCT mandible models. Eleven landmarks placed on the models defined six linear measurements (lateral condyle, gonion, and endomolare width, ramus and mental depth, and mandible length) and three angular measurements (gonion, gnathion, and lingual). A fourth degree polynomial fit quantified growth trends, its derivative quantified growth rates, and a composite growth model determined growth types (neural/cranial and somatic/skeletal). Sex differences were assessed in four age cohorts, each spanning five years, to determine the ontogenetic pattern producing sexual dimorphism of the adult mandible.ResultsMandibular growth trends and growth rates were non-uniform. In general, structures in the horizontal plane displayed predominantly neural/cranial growth types, whereas structures in the vertical plane had somatic/skeletal growth types. Significant prepubertal sex differences in the inferior aspect of the mandible dissipated when growth in males began to outpace that of females at eight to ten years of age, but sexual dimorphism re-emerged during and after puberty.ConclusionsThis 3D analysis of mandibular growth provides preliminary normative developmental data for clinical assessment and craniofacial growth studies.     

Correlation of the periodontal status 6 years after puberty with clinical and microbiological conditions during puberty

Abstract The purpose of this study was to assess the oral clinical and microbiological status of young adults 6 years after puberty and to compare these findings with the conditions observed during puberty. Clinical and microbiological parameters were monitored in 42 individuals 10 × between the ages of 11 and 14 years. 33 individuals were re-examined 10 years after the start of this monitoring. Microbiology included 2 subgingival samples per subject taken from the mesiobuccal aspects of the upper 1st molars. The samples were subject to continuous anaerobic culturing. Individuals with a marked and sustained increase in mean papillary bleeding scores during puberty (group A, n=16) differed 6 years later from individuals without pronounced puberty gingivitis (group C, n=8) in several aspects. Individuals in group A had a significantly higher gingival bleeding tendency and an increased number of sites with more than 3 mm attachment loss. The subjects in group C showed the lowest anaerobic total cultivable counts. Spirochetes were detected only in group A subjects (4 samples in 3 individuals). In all positive sites, spirochetes had been identified at least 8 out of 10 times during puberty. A. actinomycetemcomitans was present in only one individual of group A. P. gingivalis had not been detected during puberty; none of the samples were P. gingivalis positive 6 years later. P. intermedia was found in 27% of all samples, isolates belonging to the P. melaninogenica group of black pigmenting anaerobes had a frequency of 6%, 6 years after puberty. These organisms were not significantly associated with a history of puberty gingivitis. This prospective study shows a relationship between the presence of puberty gingivitis and periodontal and microbiological conditions 6 years after puberty.