Angle Ⅱ^1类错[牙合]畸形牙弓及基骨形态的测量分析

目的 通过比较上海地区Angle Ⅱ1类及个别正常[牙合]青少年牙、牙弓及基骨形态,为正畸临床诊断和治疗提供理论依据.方法 以上海地区个别正常[牙合]青少年50例（男女各25例）为对照组 以Angle Ⅱ^1类50例（男女各25例）为实验组.分别测量牙量,牙弓宽度及长度,基骨宽度及长度.用SPSS.13.0统计软件对测量结果进行统计分析.结果 （1）牙弓形态：实验组上颌中段和后段牙弓宽度显著减小,上颌前段,下颌各段牙弓宽度与对照组无显著差异.上下颌各段牙弓长度显著增加.（2）基骨形态：实验组上颌基骨宽度显著减小,基骨长度显著增加 下颌基骨形态与对照组无显著差异.（3）牙量：实验组上下颌牙量均显著增加.结论 （1）Angle Ⅱ^1类患者未发现尖牙区和下颌牙弓狭窄,提示临床上尽量不要轻易扩展上颌尖牙区和下颌牙弓宽度.（2）Angle Ⅱ^1类患者上颌牙弓和基骨均显狭长.     

Angle Ⅱ~1类错畸形牙弓及基骨形态的测量分析

目的通过比较上海地区AngleⅡ1类及个别正常青少年牙、牙弓及基骨形态,为正畸临床诊断和治疗提供理论依据。方法以上海地区个别正常青少年50例(男女各25例)为对照组;以AngleⅡ~1类50例(男女各25例)为实验组。分别测量牙量,牙弓宽度及长度,基骨宽度及长度。用SPSS.13.0统计软件对测量结果进行统计分析。结果(1)牙弓形态:实验组上颌中段和后段牙弓宽度显著减小,上颌前段,下颌各段牙弓宽度与对照组无显著差异。上下颌各段牙弓长度显著增加。(2)基骨形态:实验组上颌基骨宽度显著减小,基骨长度显著增加;下颌基骨形态与对照组无显著差异。(3)牙量:实验组上下颌牙量均显著增加。结论(1)AngleⅡ~1类患者未发现尖牙区和下颌牙弓狭窄,提示临床上尽量不要轻易扩展上颌尖牙区和下颌牙弓宽度。(2)AngleⅡ~1类患者上颌牙弓和基骨均显狭长。     

第二恒磨牙正锁[牙合]畸形相关因素的研究

目的探讨引发下颌第二磨牙正锁(牙合)的相关因素,为口腔正畸临床诊断和治疗提供参考。方法随机抽取800例符合条件的病例作为研究对象。男349例,女451例,平均年龄21.7±3.31岁,其中45例发生第二磨牙正锁(牙合)。测量上颌后段牙弓间隙,下颌后段牙弓间隙,ANB角,上颌第一磨牙区和上颌第二磨牙区的牙槽弓宽度和下颌第一磨牙区和下颌第二磨牙区的牙槽弓宽度,对测量值进行统计分析。结果第二磨牙正锁(牙合)的发生率为5.6%,其性别构成差异无显著性(P>0.05)。回归方程:第二磨牙正锁(牙合)=22.9748 2.0257×上颌后段牙弓拥挤度 1.5372×下颌后段牙弓拥挤度 1.0071×ANB角度 0.3785×上颌第二磨牙处牙槽弓宽度-0.4897×下颌第二磨牙处牙槽弓宽度。结论第二磨牙正(牙合)与上颌后段牙弓拥挤有显著的相关关系,与下颌后段牙弓拥挤度、ANB角度和上颌第二磨牙处牙槽弓宽度呈正相关关系,与下颌第二磨牙处的牙槽弓宽度呈负相关关系。     

无尾蹄蝠在云南再次发现

１９９８年４月８日笔者在云南省凤庆县小湾镇小湾村公所江边村（即漫湾电站水库的北端）采得５号蝙蝠标本,经鉴定为无尾蹄蝠（ＣｏｅｌｏｐｓｆｒｉｔｈｉＢｌｙｔｈ,１８４８）。此系云南省首宗发现;亦为自１９２８年以来中国大陆第二次报道。５号标本中,１♀４♂;平均体重３－２８ｇ,体长３７－２０ｍｍ,尾长１－２０ｍｍ,后足长７－１０ｍｍ,耳长１２－８０ｍｍ;前臂长３５－０２ｍｍ,胫长１４－２８ｍｍ。Ｅｌｌｅｒｍａｎｅｔａｌ．（１９５１）将分布于我国的无尾蹄蝠分为４个亚种,即：指名亚种Ｃ－ｆ．ｆｒｉｔｈｉ,福…     

生长发育期上颌牙列严重拥挤患者30例未拔牙治疗机制探讨

目的:探讨生长发育期牙弓宽度宽变化的可塑性的限度及规律,尽可能减少正畸治疗中拥挤患者的拔牙比率.方法:通过回顾性分析选出我科十年来治疗完成的、采用未拔牙手段治疗成功的病例100例.从中选出30例严重拥挤病例,其中男18例,女12例,平均年龄11.2岁,对其治疗前后牙弓宽度长度及拥挤部位进行比较分析.结果:尖牙唇侧错位造成间隙不足的患者,通过牙弓前段和中段宽度的增加来解除拥挤排齐牙列,治疗前后比较,有显著性差异;牙齿腭侧错位造成拥挤的患者,通过拥挤对应区段长度的增加来解除拥挤,治疗前后比较,差异有显著性.结论:生长发育期严重拥挤惠者可通过牙弓长度或宽度的生长适应性改建而非绝对拔牙手段采解除拥挤.     

颈静脉和后腔静脉导管安置方法

在动物体内不同部位安置颈静脉导管是进行生殖内分泌研究的重要基本方法之。本文介绍了奶山羊颈静和后腔静脉导管的安置和使用方法。导管为长约１米、内径１、５ｍｍ、外径２．２ｍｍ的硅胶管。导管插入血管的深度约为８－１０ｃｍ，另一端在皮下潜行约２０－２５ｃｍ后穿出体外，并安装带盖针头。每次采样后在导管内注满稀释为４０单／ｍｌ的肝素以防止血液凝结在导管内，防止经导管注入气泡或引起感染，一般可维持两以上连续采样。     

延吉市朝鲜族汉族儿童体格发育及遗传因素的研究

调查了１５０６名朝鲜族,汉族４－７岁儿童体格发育情况。朝鲜族儿童平均身高和坐高皆低于汉族儿童相同年龄组,而平均体重却高于汉族同龄组;在头围、胸围指标中汉族男、女儿童４－５岁之间大于朝鲜族同龄组,但自５岁以后朝鲜族超过治疗组,可以看出,朝鲜族儿童体格为相对矮壮,而汉族儿童相对瘦高。又对朝、汉族儿童身同父母平均身高进行单变量相关分析显示出显著意义相关。延吉市朝、汉族儿童各项指标低于９１８５年全国九市效     

T4K矫治器治疗替牙早期Ⅱ类错合患儿的临床疗效以及预后研究

目的:研究T4K矫治器治疗替牙早期Ⅱ类错合患儿的临床疗效以及预后。方法:选取从2015年2月到2017年3月在我院接受治疗的48例替牙早期Ⅱ类错合患儿进行研究。采用T4K矫治器治疗患儿6个月,对比患儿治疗前及治疗6个月后的模型测量值、X线头影测量数据以及上面高、下面高、下面高比例,随访3年,分析X线头颅侧位片的检测数据。结果:患儿治疗6个月后的前牙覆合值、前牙覆盖值、上牙弓拥挤度、下牙弓拥挤度均较治疗前明显更低,上牙弓宽度和下牙弓宽度较治疗前明显更高,差异均有统计学意义(均P0.05)。治疗6个月后患儿的SNA角、ANB角以及U1-SN角和覆盖均较治疗前明显降低,SNB角、L1-MP角以及U1-L1角和下颌平面角均较治疗前明显升高,差异均有统计学意义(均P0.05)。治疗6个月后患儿的上面高、下面高以及下面高比例均较治疗前明显增加,差异均有统计学意义(均P0.05)。随访3年显示,ANB角和L1-MP角较治疗6个月后明显降低(P0.05),而SNB角、U1-L1角、下颌平面角、上面高、下面高、下面高比例、覆盖均较治疗6个月后明显增高(P0.05)。结论:应用T4K矫治器对替牙早期Ⅱ类错合患儿进行治疗的疗效较好,有利于其康复和预后,值得在临床上给予相应的推广。     

体能训练对宜昌市西陵区儿童体质发育的影响

目的:评价体能训练对儿童体质发育的影响,探索能促进儿童体质发育的训练模式。方法:整群随机抽取宜昌市西陵区4所幼儿园,将儿童随机分成试验组和对照组,最终纳入试验组312人,对照组301人。试验组儿童进行为期1年的各项体质训练干预,对照组儿童给予常规教学。比较训练前后儿童各项体质指标、出勤率及近视率。结果:经过1年干预训练后,两组各年龄组儿童在身高、体重形态指标上无显著性差异(P0.05);素质指标中,与对照组相比,试验组各年龄组儿童在10 m折返跑、立定跳远、网球掷远、双脚连续跳、坐位前体屈5个项目上组间差异均有统计学意义(均P0.05);而在走平衡木项目上,只有7岁年龄段组间差异有统计学意义(P0.05);试验组出勤优秀率显著高于对照组(P0.05);两组近视率在干预前后差异均无统计学意义(P0.05)。结论:开展儿童体质训练能够促进儿童体质发育,应在各幼儿园广泛推广。     

2850例儿童血铅检测结果分析

目的 了解儿童体内血铅的含量,为儿童铅中毒的防治提供科学依据.方法 采用原子吸收光谱法,对沈阳市妇婴医院2011年8月至2012年10月儿科门诊2 850例0 ～14岁儿童进行铅测定.结果 2 850例儿童中不同年龄组血铅中毒比例分别为2.67％、2.74％、3.12％和3.15％,血铅中毒比例随年龄增长略有增加.但各年龄组间比较差异无统计学意义(x2=-0.15,P＞0.05).其中血铅＜100 μg/L为2 769例,血铅轻度中毒81例,铅中毒率为2.85％,差异有统计学意义(x2=10.15,P＜0.05).结论 血铅含量随着年龄增长在增多,男童铅中毒比例高于女童.建议早发现,早诊断,早治疗,以确保儿童健康成长.     

Coronal breadth of human primary anterior teeth

Original data for mesiodistal diameter of deciduous anterior teeth on 180 White children show: (1) mean size is smallest for the lower central incisor and largest for the upper canine, (2) means from combining widths on the left anterior teeth of each arch are larger in the maxilla than the mandible by 4.0 mm, (3) individual differences for widths of the upper central and lateral incisors extend from one child with these teeth of similar size to another child with the central incisor larger than the lateral by 2.3 mm, and (4) anterior tooth correlations are positive, varying from r = 0.4 for upper canine width with width of lower central incisor, to r = 0.8 for combined widths of left anterior teeth in the maxilla with combined widths of their antagonists. Comparative findings are drawn from investigations on Australian aborigines, South African Bushmen, Liberian Negroes, Tristan da Cunha islanders, Japanese, Japanese-Negro admixtures, Japanese-White admixtures, White groups living in several parts of Europe, and North American Whites. Among these ethnic groups, Australian aborigines have the largest deciduous anterior teeth. Composite means on each sex for North American Whites show boys to have slightly larger anterior deciduous teeth than girls.     

Activity pattern, smoking habits, and somatometric variables of the Czechoslovakian population

A total of 3762 subjects of both sexes, natives of Czechoslovakia, ranging in age from 12--55 years, were examined. Both anamnestic data and selected anthropometric variables were evaluated. The proportion of non-smokers for adult males was 47--56%, and for adult females was 54--74% of the population. The proportion of subjects not engaged in any type of physical activity decreases in boys between 12 and 18 years from 28 to 16%, in girls between 12 and 15 years from 25 to 22%; from then on the trend reverses and the percentages rises up to 42% in men and 65% in women. The number of subjects participating in competitive sporting activity reaches its peak at 18 years, when 46% of boys annd 43% of girls compete, but then decreases quickly. 12 year old girls are taller and heavier than boys but at 15 years the relationship is reversed. The LBM at the age of 12 is equal in boys and girls, but from then till 18 years the increase is larger in boys. The LBM weight in adults remains steady, women attaining 77% of the value found in men. The skinfold increases with age similarly in both sexes, except for an interval between 12 and 18 years, when girls show a steeper increase. Adult women attain 121--160% of the values characteristic for men. The grip strength of the right hand equals about 50 kp in adult men and 30 kp in adult women. Within the age range followed, it remains unaffected by age.     

Are the Recent Secular Increases in Waist Circumference among Children and Adolescents Independent of Changes in BMI?

Background

Several studies have shown that the waist circumference of children and adolescents has increased over the last 25 years. However, given the strong correlation between waist circumference and BMI, it is uncertain if the secular trends in waist circumference are independent of those in BMI.

Methods

We analyzed data from 6- to 19-year-olds who participated in the 1988–1994 through 2011–2012 cycles of the National Health and Nutrition Examination Survey to assess whether the trends in waist circumference were independent of changes in BMI, race-ethnicity and age.

Results

Mean, unadjusted levels of waist circumference increased by 3.7 cm (boys) and 6.0 cm (girls) from 1988–94 through 2011–12, while mean BMI levels increased by 1.1 kg/m² (boys) and 1.6 kg/m² (girls). Overall, the proportional changes in mean levels of both waist circumference and BMI were fairly similar among boys (5.3%, waist vs. 5.6%, BMI) and girls (8.7%, waist vs. 7.7%, BMI). As assessed by the area under the curve, adjustment for BMI reduced the secular increases in waist circumference by about 75% (boys) and 50% (girls) beyond that attributable to age and race-ethnicity. There was also a race-ethnicity interaction (p < 0.001). Adjustment for BMI reduced the secular trend in waist circumference among non-Hispanic (NH) black children (boys and girls) to a greater extent (about 90%) than among other children.

Conclusions

Our results indicate that among children in the U.S., about 75% (boys) and 50% (girls) of the secular increases in waist circumference since 1988–94 can be accounted for by changes in BMI. The reasons for the larger independent effects among girls and among NH blacks are uncertain.     

Health condition of first permanent molars in year 1977 and 2007 in children in Istria (Croatia)

The aim of this study was to examine differences between health condition of the first permanent molar (M1) in children in 1977 and 2007. The materials for the study consisted of data on the health condition of M1 determined in a study in 1977 (Group I) for children from the district of Buje in Istria. The health condition of M1 was examined again in the same area in 2007 (Group II). The first permanent molar is most frequently affected by caries and represent a good indicator for general caries incidence of children. Study included 709 subjects in Group I (363 boys, 346 girls) and 460 subjects in Group II (242 boys, 218 girls), aged from 6 years and 0 months to 12 years and 5 months. The difference in the frequency of intact, decayed, filled and missingd M1 was examined in both groups. Chi2 test was used to determine the differences between the number of I (intact), D (decayed), F (filled) and M (missing) teeth for each age group in Group I and Group II. In Group I there were 29.3% intact, 48.9% decayed, 17.4% filled and 4.3% missing M1, and in Group II there were 53.0% intact, 22.6% decayed, 22.1% filled and 2.1% missing M1. During the period of 30 years, a significant increase of number of dental surgeries, and thus better preventive and health education, resulted in the significant increase in the number of intact (24.0%) and filled (4.7%) M1, and decrease in the number of decayed (26.3%) and missing (2.2%) M1. From 1977 to 2007, the number of intact M1 in group II increased considerably according to group I, while the number of decayed M1 in group II significant decreased according to group I. These changes were the result of a considerably increased number of dental surgeries.     

Longitudinal analysis of adolescent growth of ladino and Mayan school children in Guatemala: effects of environment and sex.

The rate of growth in height and the timing of adolescent growth events are analyzed for two samples of Guatemalan children. One sample includes Mayan school children, 33 boys and 12 girls between the ages of 5.00 to 17.99 years, living under poor conditions for growth and development. The second sample includes ladino children, 78 boys and 85 girls of the same age range, living under favorable conditions for growth. The Preece-Baines model I function is used to estimate mean values for rates and timing of childhood and adolescent growth events for the two groups. Significant statistical contrasts (t-tests) of these means show Mayan boys reach the age of "take-off" (TO; the onset of the adolescent growth spurt) 1.45 years later, achieve peak height velocity (PHV) 1.68 years later, and continue growing for about 2.0 years longer than do the ladino boys. Despite the Mayan boys' increased duration for growth they grow significantly more slowly than the ladinos. Mayan boys are 6.60 cm shorter than ladinos at the age of TO and are estimated to be 7.71 cm shorter than the ladinos at adulthood. Mayan girls reach the age of TO 0.93 years later than do the ladina girls, but the two groups do not differ in the age at PHV or the age at adulthood. The mean height of Mayan girls is significantly less than that of ladinas at the age of TO (6.5 cm), and this difference increases to an estimated 11.14 cm at adulthood. Possible causes of these ethnic and sex-related differences in amounts and rates of growth are discussed in relation to hypotheses about the genetic and environmental determinants of human development.     

Age-related,interindividual, and right/left differences in anterior-posterior foot pressure ratio in preschool children

Background

This study aimed to examine age-related, interindividual, and right/left differences in anterior-posterior foot pressure ratio in 764 preschool children (364 boys and 400 girls) aged 3.5-6.5 years.

Methods

Subjects maintained an upright standing posture for 10 seconds on the Footview Clinic, an instrument designed to calculate the anterior-posterior foot pressure ratio. The ratio of anterior foot pressure in each subject’s right and left feet was selected as a variable, and the mean of a 10 s measurement was used for analysis.

Results

The ratio of anterior foot pressure was significantly larger in the right foot than in the left foot. With regard to age, the ratio of anterior foot pressure was significantly larger in children aged over 4.5 years than in children aged 3.5 years. It was also larger in children aged 6 and 6.5 years than in children aged 4 years. Interindividual differences in variables were large, and coefficients of variance were highest in children aged 3.5 years and lowest in children aged 6.5 years.

Conclusions

In conclusion, anterior foot pressure increases with age in preschool children. Interindividual differences in anterior foot pressure are large and tend to decrease with age. Furthermore, the anterior foot pressure is slightly higher in the right foot than in the left foot. These results will be useful for various studies, such as examining relationships between the anterior-posterior foot pressure ratio and factors, such as untouched toes, physical fitness, and level of exercise.     

38年来济南、青岛儿童少年生长的长期变化

本文分析了济南、青岛1962—2000年7—18岁儿童少年生长发育的长期变化趋势。38年间,济南市7—18岁男女生身高平均增长15 48cm(男)、12 09cm(女),体重平均增长15 76kg(男)、10 01kg(女),胸围平均增长7 88cm(男)、4 10cm(女);青岛市7—18岁男女生身高平均增长17 12cm(男)、13 19cm(女),体重平均增长16 98kg(男)、10 46kg(女),胸围平均增长6 72cm(男)、3 05cm(女)。青岛市男女生身高的增长幅度显著大于济南。     

Changes in the human fat mass from the ages of 6 to 18

In 2,300 persons of both sex, 6, 8, 10, and 18 years of age, using the caliper of "Holtein"-type for measuring thickness of skin-fat folds, age dynamics in distribution of subcutaneous fat, as well as general, subcutaneous and internal fat have been estimated. Both in boys and girls at the age of 6-12 years the place of the greatest accumulation of the subcutaneous fat is the anterior surface of the femur; its least layer up to 10 years of age is localized on the brachium, and at the age of 12 and 18 years--on the forearm. The subcutaneous fat mass from 6 up to 12 years of age increases more than 3 times, while the body mass at the same time increases only by 91-98%. The most significant increment of the general fat mass is noted at 10-12 years of age. In 6-year-old children the part of the subcutaneous fat in the body mass is less than that of the internal fat. By 12 years of age the relative mass of the subcutaneous fat increases, and that of the internal fat remains practically the same. This, evidently, demonstrates that equilibrium between volumetric characteristics of tissues in the internal medium of the organism is preserved in the process of its age development. Up to 12 years of age sexual differences in the dynamics of all the parameters are insignificant. Comparing with the adolescents, in 18-year-old boys fat mass--body mass ratio decreases, and in the girls it continues to increase.(ABSTRACT TRUNCATED AT 250 WORDS)     

Three-dimensional assessment of transverse dentoskeletal mandibular dimensions after utilizing two designs of fixed mandibular expansion appliance: A prospective clinical investigation

The aim of this clinical study was to evaluate and compare the dentoskeletal transverse mandibular arch dimensions following the use of two designs of fixed mandibular expanders using cone beam computed tomography (CBCT). Twenty orthodontic patients, 12 females and 8 males, with mean age of 13.4 ± 0.5 years were selected and randomly divided into two equivalent groups; group A consisted of 10 patients (4 boys, 6 girls) who were treated with modified Williams expander and group B consisted of 10 patients (4 boys, 6 girls) who were treated with a two-arm fixed expander. Consistent expansion instructions were given to all patients according to a standardized slow protocol of one quarter turn twice/week for both expanders. Routine orthodontic records as well as mandibular CBCTs were obtained before (T1) and immediately after expansion (T2) to estimate changes in dentoskeletal mandibular transverse dimensions. The data was statistically analyzed and the significance level was set at p ≤ 0.05. Mandibular intercanine, inter-premolar, intermolar widths; and arch perimeter were significantly increased (p ≤ 0.05) following expansion with both fixed expanders. However, the changes in inter-premolar width, intercanine width, and arch perimeter were significantly augmented in two-arm fixed expander group than modified Williams’s group. In contrast, their effects on the skeletal mandibular body width were non-significant (p > 0.05). Both expanders yielded significant and equivalent dentoalveolar effects that were more evident with two-arm fixed expander than the William one. Both fixed designs enhanced mandibular transverse dental dimensions; however, they were unsuccessful to create any considerable skeletal effects.     

Racial Differences in the Tracking of Childhood BMI to Adulthood

Objective: The possibility that there are racial differences in the patterns of BMI (kilograms per meter squared) change throughout life has not been examined. For example, the high prevalence of obesity among black women could result from a higher prevalence of obesity among black girls or because normal‐weight black girls experience larger BMI increases in adolescence or adulthood than do their white counterparts. Therefore, we examined the tracking of childhood BMI into adulthood in a biracial (36% black) sample. Research Methods and Procedures: Five‐ to 14‐year‐old children (2392) were followed for (mean) 17 years. Childhood overweight was defined as BMI ≥ 95th percentile, and adult obesity was defined as BMI ≥ 30 kg/m². Results: The tracking of childhood BMI differed between whites and blacks. Among overweight children, 65% of white girls vs. 84% of black girls became obese adults, and predictive values among boys were 71% (whites) vs. 82% (blacks). These racial differences reflected contrasting patterns in the rate of BMI change. Although the initial BMI of black children was not higher than that of white children, BMI increases with age were larger among black girls and overweight black boys than among their white counterparts. In contrast, relatively thin (BMI < 50th percentile) white boys were more likely to become overweight adults than were their black counterparts. Discussion: These findings emphasize the black/white differences in BMI changes with age. Because of the adult health consequences of childhood‐onset obesity, early prevention should be given additional emphasis.