Oligodontia in Danish schoolchildren

Oligodontia is a rare condition, and only limited data are available on its prevalence. The present paper is based on data from Danish schoolchildren. When these data are combined with comparable data on Danish schoolchildren published previously by the senior author, it is shown that oligodontia occurs in 0.16% of the children (95% confidence interval, 0.07% to 0.30%). Two of every three congenitally missing teeth were upper or lower second premolars or upper lateral incisors. When data from Danish schoolchildren were combined with population data from similar groups of schoolchildren from the Nordic countries, the condition was found to be more frequent in girls than in boys (P = 0.05).     

Prosthodontic Rehabilitation with a Telescopic Prosthesis of a Nonsyndromic Oligodontia Patient

Oligodontia is the congenital absence of six or more permanent teeth, excluding the third molars. Oligodontia of permanent dentition is a rare occurrence. Preservation of the remaining deciduous dentition in such situations is important for both functional and esthetic rehabilitation of the patient. This clinical report describes the rehabilitation of a 16‐year‐old male with oligodontia of permanent teeth treated by an interdisciplinary team of prosthodontist, pedodontist, and orthodontist. The remaining deciduous dentition was endodontically treated. Occlusal vertical dimension (OVD) of the deciduous dentition was assessed. A full‐mouth single piece porcelain‐fused‐to‐metal telescopic prosthesis for the maxillary and mandibular arches was planned with a minimal increase in OVD. The telescopic prosthesis provided excellent retention, stability, esthetics, and stress equalization on the remaining deciduous dentition. Maintenance of oral hygiene procedures was simplified for the adolescent with the telescopic prosthesis. Preservation of remaining deciduous dentition and fabrication of a telescopic prosthesis in this patient provided an effective esthetic and functional rehabilitation.     

少牙畸形患者牙弓长度和宽度的临床研究

目的研究少牙畸形患者牙弓的长度和宽度,为临床诊治提供参考。方法选取少牙畸形与正常的牙模型各50副,用游标卡尺测量并计算牙弓长度和宽度的各项参数,采用ANOVA法进行统计分析。结果少牙畸形患者较正常的上、下牙弓长度分别少4.40mm和2.80mm,上、下颌尖牙宽度分别少2.82mm和2.70mm,上、下颌磨牙宽度分别少3.40mm和1.80mm。两组测量项目的差异均有统计学意义(P<0.01)。结论正畸治疗时,应当考虑到少牙畸形患者的牙弓长度和宽度均较正常小。     

Investigation of Craniofacial Morphology in Patients with Hypo- and Oligodontia

Abstract Aim: This cephalometric study was performed with the intention to qualify and quantify differences between the craniofacial morphology in persons with congenitally missing teeth (hypo- and oligodontia) in comparison with the craniofacial morphology in persons without missing teeth. Patients and Methods: Lateral cephalograms of 42 (21 female, 21 male) patients were traced. Patient mean age at the time the radiographs were taken was 13.39 ± 7.30 years. The sample was divided into two groups: There were 22 patients in the oligodontia group (11 f, 11 m). The group of those with hypodontia contained 20 persons (10 f, 10 m). The growth study by Riolo et al. [15] served as the control. Results: Patients with congenitally missing teeth compared to those with complete dentition showed reduced maxillary and mandibular length (p < 0.001). The mandible was prognathic, the chin positioned more anteriorly (∠SNB p < 0.05, ∠SNPog p < 0.01). The overall anterior face height was noticeably lower as a result of the shortening of both upper anterior and lower anterior face heights (p < 0.001). Comparison between patients with oligodontia and those with hypodontia revealed statistically significant differences in only two dentoalveolar measurements. Conclusion: There were significant morphologic differences between patients with congenitally missing teeth and patients with complete dentition. Additional differentiation between oligodontia and hypodontia revealed only few differences. Parts of the results were presented at the 77th Congress of the German Orthodontic Society (DGKFO) in Freiburg 2004.     

Hypodontia of permanent teeth in Danish schoolchildren

Hypodontia, congenitally missing teeth, is one of the conditions recorded during systematic orthodontic screening of groups of children attending a community child dental health service. The present investigation reports the prevalence of hypodontia in 3325 9–10-year-old children in the 3rd schoolgrade examined with an orthopantornographic radiograph. The prevalence of children with hypodontia was found to be 7.8%. Fifty percent of these children were missing only one tooth while 85% were missing either one or two teeth. More teeth were missing in the mandible than in the maxilla. The teeth most frequently missing were the second premolars, representing 67% of the congenitally missing teeth. Symmetrical hypodontia of second premolars occurred approximately twice as often in girls as in boys. Though more teeth were congenitally missing in girls than in boys, no difference could be seen in the prevalence of hypodontia in boys (7.7%) and girls (7.8%).     

Estimates of orthodontic treatment need in Danish schoolchildren

ABSTRACT Orthodontic treatment need has been assessed on the basis of complete orthodontic records in a random sample of 293 Danish children aged 13–17 years by a group of postgraduate orthodontic students and by three orthodontists. The estimates of treatment need ranged from 45 % to 61 %. Interexaminer agreement in pairs was observed in 77 %– 92 % (mean 83 %) of the cases. Uniformity in four individual assessments was reached in 69 % of the cases: 38 % were considered in need of treatment and 31 % were considered not to present such need; conversely, 31 % gave rise to disagreement. It is argued that, at present, the orthodontist's subjective estimate of treatment need probably constitutes a more realistic approach to the problem of assigning treatment priority than the various indices of malocclusion.     

上海市静安区800名老年人口腔健康状况调查

目的 了解静安区老年人口腔健康状况,探索社区老年人口腔保健新措施。方法 上门检查800例60－74岁老年人的口腔健康状况。指数和标准参照全国第二次口腔流行病学调查的标准。结果 龋病患病率为80．15％,牙龈炎患病率为66．42％,牙周病患病率为32．38％,牙列缺损患病率为88．13％,牙列缺失患病率为16．25％,楔状缺损患病率为54．63％。结论 老年人口腔健康状况较差,缺乏自我保健意识。提示：在社区卫生保健服务中,应有计划、有目的的对老人进行卫生宣教,并实施预防、康复治疗。     

Relationship between dental and skeletal maturation in Danish schoolchildren

Abstract – Spearman correlation coefficients between the number of emerged permanent teeth and RUS (TW2 method) skeletal maturity scores were calculated among 1412 boys and 1332 girls, aged 7–14 yr, divided into 3-month age groups. "Moving averages" are presented of the correlation coefficients for every four 3-month age groups at a time. The pattern of the correlations differed between the sexes. However, in general, weak associations were found (mean r = 0.15-0.16), but correlations were significant at the 1%, level in 8.5-9.5-yr-old girls and around 12 yr in both sexes. It is argued that skeletal, rather than dental, maturity should be assessed in adopted non-European children of unknown chronologic age.     

Relationship between dental and skeletal maturation in Danish schoolchildren

Spearman correlation coefficients between the number of emerged permanent teeth and RUS (TW2 method) skeletal maturity scores were calculated among 1412 boys and 1332 girls, aged 7-14 yr, divided into 3-month age groups. "Moving averages" are presented of the correlation coefficients for every four 3-month age groups at a time. The pattern of the correlations differed between the sexes. However, in general, weak associations were found (mean r = 0.15-0.16), but correlations were significant at the 1% level in 8.5-9.5-yr-old girls and around 12 yr in both sexes. It is argued that skeletal, rather than dental, maturity should be assessed in adopted non-European children of unknown chronologic age.     

Prevalence and genetic basis of tooth agenesis

Tooth agenesis or hypodontia is one of the most common anomalies of the human dentition, characterized by the developmental absence of one or more teeth. Many studies have reported that the prevalence of congenital absence of permanent teeth varies from 3% to 11% among European and Asian populations. Recent advances in the fields of molecular biology and human genetics have improved our understanding of the cause of tooth agenesis. In this review, we assess the previous literature on prevalence of tooth agenesis comparing the Japanese with other racial populations, and describe the recent genetic studies associated with hypodontia in human and mouse models.     

Caries among Danish schoolchildren in birth-cohorts 1950–78

Data on caries prevalence are reported from 8- and 16-yr-old children living in a Danish community which established the Public Child Dental Health Service in 1957. Every fourth birth-cohort from 1950 through 1970 was followed longitudinally. In the 8-yr-olds, caries prevalence decreased in the primary dentition from 17 to 3 dmfs and in the permanent dentition from 3.4 to 0.3 DMFS over a 28-yr period. Among the 16-yr-olds, a reduction was observed from 16.4 to 5.1 DMFS over 20 yr. Time trends in the decreasing caries prevalence are related to various organizational events and preventive measures. Moreover, the possible influence of general changes in living conditions and health behavior is pointed out.     

A comparative radiographic investigation of caries prevalence in Danish schoolchildren

In order to assess the prevalence of untreated caries in two groups of Danish 7th grade (13- to 14-year-old) school children in a blind study, a radiographic investigation was carried out. Only half of the children (394) had received regular school dental care during their years of attendance of primary school; the other children (368) had not. A bitewing radiograph of the right side of the mouth of each child was taken, employing a standardized technique. The radiographs were read without the examiner knowing the group identity of the radiographs. The criteria for discarding poor radiographs, teeth, and tooth surfaces are described. Some of the radiographic results are compared with the clinical caries score of the same group. Most of the radiographs without untreated caries were found among those of the children who received school dental service. Uncertainty of method in connection with radiographic investigation is discussed.     

苏州市区中学生恒牙龋病牙周病流行病学调查

目的 调查苏州市区初一和高二学生恒牙龋病和牙周病流行病学情况。方法 按“全国学生龋齿牙周疾病调查表”的要求进行。结果 对２０５８１名初一、高二学生进行恒牙龋病牙周病的流行病学调查。初一组学生恒牙的平均患龋率、龋均和龋面均分别为２３．６４％、０．４０％和０．５４;第二组学生的平均患龋率、龋均和龋面均分别为２９．７６％、０。６４％和０．８９。初一学生的牙龈炎和牙石发生率分别为７５．３３％;高二组学生的     

Dental caries in schoolchildren of an Estonian and a Danish municipality

Objectives . The objectives of the study were to describe the prevalence rate and the severity of dental caries in Estonian schoolchildren aged 7 and 12 and to compare the findings with those of Danish children.
Design . Cross-sectional surveys in Estonia and Denmark, clinical oral examinations of children in 1997.
Samples and methods . In Estonia, 195 children aged 7 and 215 children of age 12 were selected in the municipality of Tartu in schools identified for oral health promotion projects. In Denmark, the study included 637 7-year-olds and 642 12-year-olds living in the municipality of Horsens and served by the Public Dental Health Service for children. All children in the two countries were examined by calibrated dentists for dental caries according to the Recording System for the Danish Public Dental Health Service.
Results . At age 7, 83·8% of Estonian children had dental caries (7·7 dmfs) against 62·1% of Danish children (5·3 dmfs). At age 12, the mean caries experience was 2·1 DMFS in Estonia against 1·3 DMFS of the Danish children. Most of the caries indices were due to the high d/D components and approximal caries was prominent. In the study area in Estonia, the content of fluoride in drinking water was optimal (0·8–1·5 p.p.m.) whereas the level of fluoride was low in the Danish municipality (0·2 p.p.m.).
Conclusion . In the Baltic states, the oral health systems are in transition. For the continuous improvement of oral health in childrens' reorientation of services should consider implementation of community-based oral health promotion and the schools provide an excellent setting for preventive oral care.     

Oligodontia in pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE) is an inherited disorder that has both autosomal recessive and autosomal dominant pathways and is characterized by severe malformation of elastic and collagen fibers. Clinically, 3 main groups of systemic findings involving skin, eye, and vessels emerge in the symptoms. In this report, we present the case of a patient with PXE who has agenesis of most of the permanent teeth. No previous reports in the English literature have mentioned oligodontia in PXE. Our treatment plan consisted of extraction of the upper left deciduous canine followed by fixed orthodontic treatment. Further prosthodontic rehabilitation was planned to restore the edentulous area.     

Periodontal status of 14–16-year-old Danish schoolchildren

Abstract – The purpose of this study was to determine the prevalence of periodontal disease in teenagers. The survey was conducted on 325 children aged 14,15 and 16 years, living in Aarhus, Denmark. Pocket depth and loss of attachment were measured in mm at the maxillary and mandibular first molars and incisors. Plaque, calculus and gingival bleeding on probing were recorded. A total of 221 children (68%) had 4–5 mm deep pockets and 19 children (5.8%) had pockets deeper than 5 mm on at least one tooth Approximately 11% of the subjects showed loss of attachment on at least on tooth. The frequency of surfaces with plaque and gingivitis was high in all three age groups. Plaque, gingivitis, deepened pockets and loss of attachment were most frequently observed on interproximal surfaces. No significant differences were observed between the sexes with regard to periodontal disease.     

Dental caries in a group of schoolchildren in Kandy,Sri Lanka

This investigation was carried out in order to collect information regarding oral health in a group of schoolchildren in Kandy, Sri Lanka. 614 children of 6, 9, 12 and 15 years were selected by stratified random sampling and examined under field conditions.

The primary dentition showed a high rate of caries on all types of surfaces. Caries in the permanent dentition was mainly located to pits and fissures below the age of 12 years, after which smooth surface caries developed. The D-component was by far the largest component of the DMF-index in both the primary and the permanent dentition.

The results are discussed in the light of the existing dental care delivery system in Sri Lanka.     

Dental caries experience in Mexican schoolchildren from rural and urban communities

OBJECTIVE: To compare dental caries experience in Mexican rural and urban settings. DESIGN: Cross-sectional samples of schoolchildren. SETTING: A school in Mexico City and a rural school in a remote area of the Oaxaca State in Southern Mexico. SAMPLE AND METHODS: A total of 347, 9- to 10-year-old schoolchildren (rural area, 131 children; urban, 216) was examined by two standardised dentists using the WHO 1987 criteria. OUTCOME MEASURES: Data were analysed in terms of central tendency measures and 95 per cent confidence intervals. RESULTS: Caries prevalence was 91.6 per cent in the urban area, and 54.4 per cent in the rural area (P < 0.05). DMFT in 10-year olds was 1.93 (sd 1.72) and 0.40 (sd 0.76) in urban and rural areas respectively (95 per cent CI 1.16-1.89). The entire DMFT/dmft indices in the rural group were made up of the decayed component. CONCLUSIONS: There is a large difference in the prevalence and distribution of dental caries between rural and urban Mexican children. Dental treatment background also differs markedly. Findings highlight the need to establish distinct preventative and rehabilitative treatment strategies tailored to meet the specific needs of different population groups.     

Association between developmental defects of enamel and dental caries in schoolchildren

Despite improvement, dental caries is still the main public oral health problem worldwide and the major cause of pain, tooth loss and chewing difficulties in children and adolescents; and it impacts negatively on oral health-related quality of life. A cross-sectional study of a multistage representative sample of 8–12-year-old Brazilian school children was carried out in order to investigate the association between enamel defects and dental caries. Children's mothers completed a questionnaire about socio-demographic and behavioural characteristics at home. Firth's bias reduced logistic regression models were undertaken to assess the association between the main exposure (enamel defects) and caries experience. The prevalence of any enamel defect was 64.0%; the prevalence of diffuse opacities, demarcated opacities and enamel hypoplasia was 35.0%, 29.5% and 3.7%, respectively. The prevalence of dental caries was 32.4%, with mean DMFT of 0.6 (SD, 1.2). Dental caries experience was more common among children who had enamel hypoplasia in their posterior teeth (OR = 2.79; 95% CI: 1.05, 6.51) than among those with none. In anterior teeth, there was no association. Enamel hypoplasia appears to be an important risk factor for dental caries.