成都市城郊地区乳牙列错(牙合)及其分布的横断面调查

目的了解成都市城郊地区乳牙列错情况,为乳牙列期错的预防性及阻断性矫治提供依据。方法对成都市双流县华阳镇幼儿园的乳牙全萌且达到接触的1279名乳牙列儿童进行调查,计算其错率。结果1279名乳牙列儿童中,错491名,错率38.38%,排列在错前5位的依次是:深覆、前牙反、切、乳牙早失、融合牙。结论成都市城郊地区乳牙列错率较高,需进一步作好乳牙列错的预防性及阻断性矫治工作。     

上海市4500名小学生替牙期错牙合畸形调查分析

目的调查上海市替牙期小学生错牙合畸形患病率及类型,为早期矫治提供科学依据。方法对7~11岁小学生随机抽样调查,按Angle错牙合分类法进行统计。结果受检小学生中错牙合畸形患病率为48.67%,男女有统计学差异。错牙合类型以AngleⅡ类最多,占50.23%。在各种错牙合畸形类型中,较为明显的是深覆盖、深覆牙合、轻度拥挤和反牙合,发生率分别是63.93%、58.90%、38.36%和18.69%。结论上海市替牙期小学生错牙合畸形患病率较高,错牙合类型构成比及主要类型发生变化,应加大力度普及错牙合畸形早期防治知识,有针对性地进行早期矫治。     

1875例错牙合患者的临床流行病学调查

作者对１９８８￣１９９３年间１８７５名正畸门诊患者进行连续调查，就本地区错牙合流行病学资料进行了分析研究。结果表明，不同牙龄组各类错牙合的分布比例及主要错牙合症状具有较大的区别，本地区Ⅱ类错牙合的发病比例较高，症状突出者显著高于全国其它地区。对错牙合的病因分析显示遗传、乳牙早失、乳尖牙磨耗不足、不良习惯、乳牙滞留是构成错牙合的前５个重要因素。临床患者女性居多，女性Ⅰ类与Ⅲ类占明显优势，男性Ⅱ类占优     

渭南地区替牙期儿童错(牙合)畸形患病情况调查分析

目的通过流行病学调查了解渭南地区替牙期儿童错(牙合)畸形患病情况。方法按照分层随机抽样的原则抽取渭南地区3所小学707名6～12岁儿童,对其咬合情况进行检查,调查与错(牙合)畸形相关的危险因素并对数据进行统计分析。结果受检儿童中有一种或多种错(牙合)畸形的患病率为34.7%,在各种错(牙合)畸形类型中深覆(牙合)患病率最高,为9.9%,有口腔不良习惯的儿童其错(牙合)畸形发生的危险性为正常儿童的2.2～6.6倍(P<0.001)。结论渭南地区替牙期儿童错(牙合)畸形患病率较高,应采取有针对的干预措施以降低其患病情况。     

上海市浦东新区青少年错牙合畸形调查分析

目的了解上海市浦东新区生长发育期青少年错牙合畸形的患病情况,重点了解牙列拥挤、前牙深覆合覆盖和前牙反牙合的患病率。方法按Ａｎｇｌｅ分类法进行分类,以个别正常牙合和错牙合分类为标准。结果错牙合畸形的患病率替牙期为４４．０２％,恒牙期为４８．７８％。牙列拥挤、前牙深覆合覆盖和前牙反牙合的患病率替牙期分别为２２．７４％、１７．１８％和４．４４％;恒牙期分别为３２．３６％、１１．０６％和４．０７％。结论上海市浦东新区生长发育期青少年错牙合畸形的患病率替牙期与恒牙期无明显差异。提示前牙深覆合覆盖和前牙反牙合的患者并伴有上下颌骨异常需尽早矫治,以改善牙合颌关系。     

泰州市海陵地区中学生错(牙合)畸形及矫治状况调查

目的:调查泰州市海陵地区中学生错(牙合)畸形患病率及治疗情况.方法:设计统一调查表,以个别正常(牙合)和Angle错(牙合)分类法为标准,对泰州市海陵地区9018名中学生进行错(牙合)畸形患病率及治疗情况调查.采用SPSS19.0软件包对调查数据进行x2检验.结果:泰州市海陵地区中学生错(牙合)畸形患病率为69.38％,错(牙合)畸形构成以安氏Ⅰ类最多,安氏Ⅱ类居中,安氏Ⅲ最少,但错(牙合)畸形矫治率较低.结论:泰州市海陵地区应加强正畸知识宣传,进一步提高正畸治疗普及率.     

819名舟山市中学生错牙合畸形及矫治状况调查分析

目的对舟山市中学生错牙合畸形发生率、矫治状况及未矫治原因作一调查研究。方法以819名舟山市中学生为研究对象,以个别正常牙合为标准,对错牙合畸形发生率、未矫治率及未进行矫治的原因进行统计分析。结果舟山市中学生错牙合患病率为78.8%,错牙合矫治率为14.3%,未进行矫治的主要原因是对错牙合的危害性认识薄弱。结论舟山市中学生呈现较高错牙合发生率及较低矫治率的特点。     

3006名乌鲁木齐市中小学生错[牙合]畸形状况调查

目的评价乌鲁木齐市3006名中小学生错畸形的流行状况。方法采用分层整群随机抽样方法,调查乌鲁木齐市7~15岁的多民族中小学生3006名,以安氏分类及个别正常作为诊断标准,检查错畸形患病情况。结果 3006名调查对象中,有错畸形患者共计1447名,患病率为48.14%。其中,安氏Ⅰ类错为1079名(占74.57%),安氏Ⅱ类错为175名(占12.09%),安氏Ⅲ类错为193名(占13.34%)。男性患病率为54.63%,女性患病率为42.19%,其差异有统计学意义(P0.05)。汉族、维吾尔族、哈萨克族和回族4个民族的患病率分别为43.28%、51.37%、40.38%和52.81%;7~9、10~12和13~15岁不同年龄段的患病率分别为41.64%、47.81%和50.62%。根据临床表现进行分类,牙列拥挤的患病率最高,其他依次为深覆、前牙间隙、深覆盖、前牙反(包括对刃)等。结论乌鲁木齐市的中小学生错畸形的患病率偏高,且在不同民族、不同性别和不同年龄之间存在差异。     

武汉市硚口区5000名高中学生错牙合畸形状况调查

目的：了解武汉市斫1：3区高中学生错殆畸形患病情况,为本地防治提供依据。方法：对武汉市研1：3区5000名17～19岁高中毕业生进行黯关系和牙颌畸形调查,按Angle错殆分类法分类。结果：本组学生错黯畸形患病率为29．26％,男生为33．81％,女生为24．91％,两者差异有显著性（P〈0．05）。错殆畸形构成比以AngleI类为最多,常见的牙殆畸形为牙列拥挤、个别牙错位、深覆殆。结论：武汉市研口区高中学生错胎畸形患病率较低,错殆畸形以AngleI类最多。     

昆明市乳牙列错畸形发病率的调查研究

目的 了解云南省昆明市市区乳牙列错情况,为乳牙期错畸形的预防性和阻断性矫治提供依据.方法 对昆明市市区3所幼儿园的乳牙全萌出且达到接触的2 116名乳牙列儿童进行调查,计算其错畸形发病率.结果 在2116名乳牙列儿童中,错1 516名,错率72％.排列在错前6位的依次是:深覆、牙列拥挤、前牙反、切、乳牙早失、开.结论 昆明市市区乳牙列错率的数据报告显示其发病率较高,需加强乳牙列错畸形的防治.     

Bite force determination in children with primary dentition

The aim of this study was to determine the bite force with primary dentition in 30 children with normal occlusion (group I), cross bite (group II) and open bite (group III). The magnitude of the bite force was determined through a pressurized transmitter tube (pressure sensor MPX 5700 Motorola), which was connected to a converse analog/digital electronic circuit. The children bit the tube with maximum force three times successively for 5 s, with a 10 s interval among each bite, and the sign was sent directly to the computer. The highest value of the three, for each patient, was considered. Analysis of variance evaluated difference among the three groups. The means of maximum bite force were 213 17, 249 63 and 241 19 N for the groups, respectively, and there were no significant statistical differences among them (P > 0.05). The analysis of correlation showed that the weight, height and bite force presented weak positive correlation (r=0.24 and 0.23). It was concluded that in the studied groups the type of occlusion did not affect the maximum values of the bite force and body variables had a small influence in this magnitude.     

Dental caries in the primary dentition: assessing prevalence of cavitated and noncavitated lesions

BACKGROUND: Dental caries in the primary dentition has received renewed attention in recent years because caries in the primary dentition is predictive of later caries experience, and because of efforts to address early childhood caries. More detailed caries diagnostic criteria have been developed and used for the permanent teeth; however, such criteria have not been widely adopted for caries diagnosis in the primary dentition. METHODS: As part of the Iowa Fluoride Study, caries diagnostic criteria were developed specifically for the primary teeth. The criteria included noncavitated (d1) lesions and cavitated (d2-3) lesions. Examinations were conducted on 698 children in the primary dentition by two trained examiners who did duplicate examinations on 11 percent (n = 67) of these children. RESULTS: Interexaminer agreement for any d1 and any d2-3 lesions at the person level was 100 percent. At the tooth level for d1d2-3f, there was 98.5 percent agreement and kappa was .91. For d1 at the tooth level, agreement was 97.0 percent agreement and kappa = .24. For d2-3 it was 99.4 percent agreement and kappa = .81. Prevalence of untreated d2-3 was 16.5 percent, while that of d1 was 24.1 percent. Nearly 73 percent had no d2-3 or filled surfaces, while over 63 percent had no d1, d2-3, or filled surfaces. Decay experience was most common on the primary second molars. About 56 percent of untreated d2-3 decay was located in the pits and fissures, while 58 percent of d1 decay was located on smooth surfaces. CONCLUSION: Despite some concern with reliability of diagnosing d1 lesions, it appears that the d1d2-3 criteria are informative and useful in assessing the primary dentition.     

成都地区混合牙列期及恒牙列初期儿童错牙合畸形患病率的调查研究

目的    调查研究成都地区混合牙列期及恒牙列初期儿童错牙合畸形的患病率,分析影响错牙合畸形发生的相关危险因素。方法    通过问卷调查及临床检查的方法,抽样调查5 ~ 13岁处于混合牙列期及恒牙列初期成都地区2056名儿童的错牙合畸形患病情况,统计错牙合畸形患病率并分析其可能的危险因素。结果    调查儿童患龋率为59.78%,龋均为2.33。混合牙列期儿童错牙合畸形患病率为64.64%,恒牙列初期错牙合畸形患病率为71.01%。错牙合畸形发生的危险因素包括龋病（OR = 3.805,95%CI：3.029 ~ 4.778,P < 0.001）、错牙合畸形遗传史（OR = 2.251,95%CI：1.219 ~ 4.156,P = 0.010）、口腔不良习惯（OR = 18.794,95%CI：9.643 ~ 36.629,P < 0.001）及食物精细（过于精细食物OR = 7.016,95%CI：4.557 ~ 10.802,P < 0.001;一般精细食物OR = 3.714,95%CI：2.587 ~ 5.333,P < 0.001）。结论    成都地区混合牙列期及恒牙列初期儿童患龋率及错牙合畸形患病率均处于较高水平;错牙合畸形发生的危险因素包括龋病、错牙合畸形遗传史、口腔不良习惯及食物过于精细。     

Assessing risk indicators for dental caries in the primary dentition

The aim of the present study was to assess indicators shown to be associated with the prevalence of caries in the primary dentition of 7-year-old Flemish schoolchildren. Cross-sectional first year data of the longitudinal Signal-Tandmobiel survey were analysed (n=4468). Gender, age, oral hygiene habits, use of fluorides, dietary habits, geographical factors and parental modelling were the considered predictors. From the multiple logistic regression analysis, including schools as a random effect, and after adjusting for the confounding variables-educational system and province (stratification variables), gender and age-it became clear that the following risk indicators remained significant (at 5% level) for the presence of caries: frequency of toothbrushing (P=0.05) with an OR 1.24 for brushing less than once a day, age at start of brushing (P<0.001) with an OR=1.22 for a delay of 1 year, regular use of fluoride supplements (P<0.001) with an OR=1.54 for no use, daily use of sugar-containing drinks between meals (P<0.001) with an OR=1.38, and number of between-meals snacks (P=0.012) with an OR=1.22 for using more than 2 between-meal snacks. There was a significant difference (P<0.05) in caries experience determined by the geographical spread, with an explicit trend of caries declining from the east to the west. In a model with an ordinal response outcome, the daily use of sugar-containing drinks between meals had a more pronounced effect when caries levels were high. From this study it became obvious that, in Flemish children, an early start of brushing and a brushing frequency of at least once a day need to be encouraged, while the use of sugar-containing drinks and snacks between meals needs to be restricted to a maximum of 2 per day. Geographical differences need to be investigated in more detail.     

Traumatic injuries in the primary dentition

Abstract  – As a support for the guidelines published in 2001, a review of the literature was carried out using the evidence-based approach in order to update the state of the art regarding epidemiology and treatment of traumatic dental injuries in the primary dentition. An online search in Medline, and a review of expert literature, lead to the conclusion that most luxation injuries heal spontaneously, and unless more conclusive evidence is available, conservative treatment of acute dental trauma for preschool children is suggested. Pain control, the dentist's ability to cope with the child's anxiety, and follow-up instructions in oral hygiene techniques will allow many primary teeth that are currently lost at the time of injury to be saved.     

Transverse dimensions of dental arches in subjects with Class II malocclusion in the early mixed dentition

Objective

The purpose of this study was to analyze the transverse dentoalveolar features of subjects with Class II Division 1 malocclusion in mixed dentition when compared to subjects with normal occlusion.

Materials and methods

The study was performed on 192 randomly selected subjects in the early mixed dentition. According to sagittal skeletal and occlusal features the sample was divided into two groups: 88 subjects (53 females and 35 males) with Class II skeletal disharmony and Class II, division 1 malocclusion (Class II Group, mean age 8 years and 10 months ± 11 months) and 104 subjects (66 females e 38 males) with dentoskeletal Class I relationships (Class I Group, mean age 9 ± 1 years). The Class II group was further divided into two subgroups (maxillary protrusion group and mandibular retrusion group) on the basis of the skeletal characteristics. Intermolar and intercanine distances were measured on dental casts in both arches and posterior and anterior transversal discrepancy (PTID and ATID) were calculated.

Results

Subjects with Class II malocclusion showed a significantly greater negative PTID (−2.1 mm) which was associated with a significantly reduced maxillary width with respect to the Class I group (−2.2 mm). The Class II group showed also a significantly greater negative ATID (−1.4 mm) when compared to the Class I group. Subjects with mandibular retrusion showed a significantly greater reduction both in the maxillary intercanine width (−1.7 mm). and in the maxillary intermolar width (−2.7 mm) with respect to the Class I group. Subjects with maxillary protrusion presented with a significantly greater constriction at the maxillary intermolar width (−1.7 mm) when compared to the Class I group.

Conclusions

Class II malocclusion with mandibular retrusion is associated with a significant constriction of the maxillary arch with reduced intercanine and intermolar widths. When Class II malocclusion is due to a maxillary protrusion the constriction at the maxillary arch is limited to the intermolar width.     

The prevalence of premature loss of primary teeth and its impact on malocclusion in the Eastern Province of Saudi Arabia

Abstract

Objectives. The present study was designed to determine the prevalence of premature loss of primary teeth and its effect on malocclusion in Eastern Province, Saudi Arabia. Materials and methods. This is an observational, cross-sectional study that included 307 male children aged 9–11 years old. Clinical examinations were performed using a disposable sharp explorer, a UNC periodontal probe and a dental mirror. The samples were examined clinically to detect the following traits: Angle’s classification of malocclusion, overjet, overbite, anterior open-bite, lateral open-bite, midline shift and cross-bite. Additionally, a dental caries examination was performed using WHO methods. Questionnaires in Arabic were coded and sent to the students’ parents. Results. The mean DMFT was 5.61 (SD = 3.01). The d-component was the highest, with a mean of 4 (SD = 2.83). Of the 307 children, it was found that 204 (66.4%) had a high DMFT score, which is defined as a score above 4. It was found that 156/307 (51%) children had premature loss of deciduous teeth. Conclusion. A high prevalence of premature loss of teeth was found in this study. This finding emphasizes the importance of increasing awareness levels about this issue and focuses attention on the need for more preventive efforts to maintain healthy and normal dentitions that would improve the masticatory function and aesthetics of individuals and the whole population. In addition, the findings emphasize the importance of the early detection of premature loss of primary teeth to prevent future malocclusion.     

乳牙期骨性Ⅱ类与Ⅲ类（牙合）颅底形态差异的研究

目的：研究乳牙期骨性Ⅱ类与Ⅲ类错（牙合）畸形患者颅底形态的差异。方法：选取乳牙期骨性Ⅱ类及Ⅲ类错（牙合）畸形患儿各20例,通过头影测量分析,比较两种骨面型患者颅底形态的差异。应用SPSSl3．0统计软件,对测量数据进行独立样本t检验及相关分析。结果：骨性Ⅱ、Ⅲ类错（牙合）患者全颅底长及后颅底倾角减小且有显著差异,后颅底长、前颅底长及颅底角减小,但变化无统计学差异。SNA角与前颅底长（S-N）、后颅底长（S-Ba）及全颅底长（N-Ba）呈显著正相关：SNB与侧颅底长（S-Ar,N-Ar）、全颅底长（N-Ba）及颅底角（NSAr,NSBa）呈显著负相关,与后颅底倾角（SBa-FH）显著正相关。结论：乳牙期不同类型错（牙合）畸形与颅底形态有关,后颅底对颅面形态影响较大。