Research issues in early childhood caries

Research 3 needed to establish what nomenclature and case definition for early childhood caries (ECC) are most relevant to health care professionals and to the public. Profiles or indexes for predicting the prevalence of ECC in communities should be developed on the basis of the socioeconomic factors, immigrant status and ethnic/racial backgrounds of populations. Future research should target risk factors of ECC, particularly prenatal and perinatal histories, nutritional status and microbiologic factors. Determining the relation of malnutrition of infants and young children, low birthweight, complicated pregnancies and traumatic births with the development of enamel linear hypoplasia deserves research attention. Factors that affect how and when infants and young children are colonized by mutans streptococci also need further study. The evaluation of chemotherapeutic preventive agents will likely yield more fruitful interventions for prevention than trying to change behaviors. Research in young children to prevent ECC, however, has particular ethical considerations. Withholding treatments or administering placebos to vulnerable subjects is not acceptable. Consequently, future clinical research likely will determine the relative rather than the absolute effectiveness of preventive regimens; the former requires large sample sizes and may necessitate multi-center studies. Human studies may be hampered by problems of recruitment, compliance and transiency of subjects. Because federal support for research on dental caries has declined in recent years, a special initiative that focuses specifically on ECC may be necessary to obtain adequate funding for research on the disease.     

Biological mechanisms of early childhood caries

The present paper reviews biological issues in early childhood caries (ECC) in light of the current understanding of the field. Despite the general global decline in dental caries in the past decades, ECC has become a significant problem in many developing countries and some minority communities in western industrialized nations. Like other types of caries, ECC is caused by mutans streptococci that ferment dietary carbohydrates to produce acid attacks on susceptible teeth over a period of time. However, while the general etiology of ECC appears similar to that of other types of caries, the predisposing factors are still unclear. The biology of ECC may be modified by several factors unique to young children, related to the implantation of cariogenic bacteria, immaturity of the host defense systems, as well as behavioral patterns associated with feeding and oral hygiene in early childhood.     

中药五倍子防龋的动物实验研究

目的研究五倍子在动物口腔内对变链菌生长及龋病发生、发展的影响。方法给大鼠感染致龋菌,并饲以致龋饲料2000#,分别用五倍子浸剂、氟化钠水溶液、蒸馏水给3组大鼠施药,用唾液取样细菌培养及Keyes龋齿评分法观察五倍子对变链菌在大鼠口内生长繁殖以及对龋齿发生发展的影响。结果变链菌计数五倍子组少于蒸馏水组（P<0.01）,与氟化钠组间无显著差异（P>0.05）。Keyes记分结果,五倍子组E级龋损和Ds级龋损均低于蒸馏水组（P<0.01）,与氟化钠组无差异(P>0.05)。Dm级龋损仅见于蒸馏水组。结论五倍子可以抑制大鼠口腔变链菌的生长和龋病发生、发展,其效果与氟化钠相当,有可能成为一种新型的防龋药物。     

早期婴幼儿龋

提要：早期婴幼儿龋是发生在婴幼儿期的与饮食密切相关的多因素作用下的慢性感染性传播性疾病。变形链球菌是在龋齿的始动和进展中的重要致病微生物。早期婴幼儿龋是一个严重的公众健康问题,它不仅累及牙齿,而且会导致多方面的健康影响。早期婴幼儿龋的防治不但需要来自口腔医疗机构和儿童口腔专科医生的关注,而且需要公众健康机构和决策者的重视。本文将对早期婴幼儿龋的病因、患病率、临床表现和危害、综合防治等问题进行讨论。     

致龋菌、唾液缓冲能力与婴幼儿龋的相关性研究

目的探讨唾液中变形链球菌、乳酸杆菌和唾液pH值、缓冲能力与婴幼儿龋的关系。方法将178名42～54个月的儿童分为患龋组（患龋牙数≥5）87例和无龋组91人。吐唾法采集非刺激性唾液和嚼蜡法采集刺激性唾液各2ml，用选择性培养的方法检测刺激性唾液中变形链球菌、乳酸杆菌的检出率和计数水平；测定非刺激性及刺激性唾液的pH值和缓冲能力。结果患龋组唾液变形链球菌和乳酸杆菌的检出率分别为96．6％和79．3％，显著高于无龋组的63．7％和27．5％（P〈0．05）；患龋组两种细菌的计数水平比无龋组高近10倍。患龋组和无龋组刺激性唾液的初始pH值和对酸的缓冲能力均显著高于非刺激性唾液（P〈0．001）；患龋组刺激性和非刺激性唾液的初始pH值和缓冲能力均显著低于无龋组（P〈0．05）；无龋组中变形链球菌、乳酸杆菌和唾液pH值、缓冲能力之间无明显的相关性；患龋组刺激性唾液的缓冲能力与变形链球菌的计数水平显著相关（r=0．249，P〈0．05）。结论变形链球菌和乳酸杆菌是婴幼儿龋的重要致病菌；唾液的初始pH值和缓冲能力偏低可能是影响婴幼儿龋的重要因素。     

Prediction of caries increment in Scottish adolescents

Salivary, clinical, and microbiological factors were compared with subsequent 2-yr caries increment in a group of 372 Scottish adolescents. The caries increment was significantly correlated with previous caries experience, salivary buffering capacity and counts of lactobacilli, mutans streptococci and candida. Veillonella levels and salivary flow rate were not correlated with caries increment. Significant improvements in the predictions were obtained when the results of more than one test were included using stepwise regression analysis. On an individual basis, using stepwise discriminant analysis, the caries increment group (low, medium, or high) was identified correctly in 49% of all subjects, but this was reduced to 45% if previous caries experience was excluded from the analysis.     

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早期婴幼儿龋是发生在婴幼儿期的与饮食密切相关的多因素作用下的慢性感染性传播性疾病。变形链球菌是在龋齿的始动和进展中的重要致病微生物。早期婴幼儿龋是一个严重的公众健康问题,它不仅累及牙齿,而且会导致多方面的健康影响。早期婴幼儿龋的防治不但需要来自口腔医疗机构和儿童口腔专科医生的关注,而且需要公众健康机构和决策者的重视。本文将对早期婴幼儿龋的病因、患病率、临床表现和危害、综合防治等问题进行讨论。     

Risk indicators for early childhood caries in Taiwan

OBJECTIVES: The purpose of this study was to investigate the prevalence, patterns, and etiological factors for caries in children. METHODS: A total of 981 children less than 6 years of age were examined using a dental mirror and explorer. A parent or a caregiver was asked to complete a questionnaire regarding information about the child, the household, and oral hygiene. The prevalence and patterns of dental caries including pit and fissure caries, facial/lingual caries, molar proximal caries, and facial/lingual molar proximal lesions, were analyzed. Each child was classified as caries free or as having one of these four caries patterns. RESULTS: Weighted mean deft was 0.14 at age 2, 2.58 at age 3, 4.41 at age 4, 6.94 at age 5, and 7.31 at age 6. Weighted mean defs was 4.71, 8.44, 16.45 and 18.64 at ages 3, 4, 5, and 6, respectively. By age 2, 5.09% of children had caries. By age 6, 89.38% of children had caries. By age 3, 30.02% of children fitted the facial and lingual pattern of caries and by age 6, 52.90% of children fit the 'facial-lingual and molar-proximal' pattern, indicating extensive smooth surface decay. The total prevalence of early childhood caries was 56%. Multivariate-adjusted odds ratios identified factors associated with the high caries experience of the young children and found caries was strongly associated with the lack of proper tooth brushing and high consumption of sweets. Higher caries scores were also associated with areas of low urbanization. CONCLUSIONS: The findings of this survey indicated a high level of untreated caries among children in Taiwan.     

Evaluation of the relationship between severe early childhood caries and vitamin D

ObjectiveTo evaluate the relationship between the factors affecting the formation of severe early childhood caries (S-ECC) in preschool children, dental caries and serum 25-hydroxyvitamin D (25(OH)D) and to contribute to the literature on this subject.MethodsASA I-II children aged <72 months and their volunteer parents who had no apparent learning disability were included in the study. 25(OH)D, calcium and albumin levels were measured from the serum samples taken from the children. Dft, dfs and plaque scores were calculated after the oral examination of the children. Parents were asked to fill out a questionnaire assessing the child's dietary habits and family demographics.ResultsTotal of 175 children (56% male) participating in the study (n = 98; ECC, n = 77; caries-free). S-ECC was present in 42.8% of children with adequate 25(OH)D levels and 63.4% of children with deficient or insufficient levels. Children with S-ECC had significantly lower mean 25(OH)D levels than those caries-free. A very weak negative correlation was detected between 25(OH)D level and dft score.ConclusionsIt was difficult to confirm the relationship between 25(OH)D levels and S-ECC. Again, there was a weak correlation between the dft score and 25(OH)D levels.     

Pattern and severity of early childhood caries

OBJECTIVES: The aim of this study was to investigate the association between selected social and behavioural variables and the pattern and severity of early childhood caries (ECC) within a community child population. METHODS: A cross-sectional sample of 2515 children aged 4-5 years were examined in a preschool setting using decayed, missing, filled teeth/surface (dmft/dmfs) indices and a self-administered questionnaire was used to obtain information regarding social, demographic, birth, infant feeding, oral and general health attitudes. Children with caries (847) were divided into anterior or posterior caries pattern groups and severe (dmfs score > or =6) or non-severe (dmfs score <6) caries groups. The data were analysed using a chi-square test and modelled using a logistic regression procedure. RESULTS: Significant variables associated with anterior ECC pattern were ethnicity other than Caucasian (OR = 2.1, 95% CI = 1.4-3.1), sipping from the bottle during the day (OR = 1.9, 95% CI = 1.3-2.7), male gender (OR = 1.6, 95% CI = 1.2-2.2) and sleeping with a bottle at night (OR = 1.5, 95% CI = 1.1-2.2). Significant variables associated with severe ECC form were sipping from the bottle during the day (OR = 2, 95% CI = 1.4-2.8), maternal age at birth < or =24 years (OR = 1.8, 95% CI = 1.3-2.7), ethnicity other than Caucasian (OR = 1.6, 95% CI = 1.1-2.5) and sleeping with a bottle at night (OR = 1.5, 95% CI = 1.1-2.2). CONCLUSIONS: Infant bottle-feeding habits (either allowing a child to sip from a bottle during the day or put to sleep at night) and ethnicity other than Caucasian were significant determinants for both anterior caries pattern and severity of ECC in 4-5-year-old Australian children.     

Prevention of early childhood caries

This paper reviews the methods used for the prevention of early childhood caries (ECC). The education of mothers or caregivers to promote healthy dietary habits in infants has been the main strategy used for the prevention of ECC. This review found that education has a modest impact on the development of ECC. While education should be promoted especially in high risk communities and population groups (low-income families and native populations), it should not be the only preventive strategy of ECC. Early screening for signs of caries development, starting from the first year of life, could identify infants and toddlers who are at risk of developing ECC and assist in providing information to parents about how to promote oral health and prevent the development of tooth decay. High risk children include those with early signs of ECC, poor oral hygiene, limited exposure to fluorides, and frequent exposure to sugary snacks and drinks. These children should be targeted with a professional preventive program that includes fluoride varnish application, fluoridated dentifrices, fluoride supplements, sealants, diet counseling, and chlorhexidine. Prevention of ECC also requires addressing the social and economic factors that face many families where ECC is endemic.     

与重症低龄儿童龋病相关的唾液微生物群落研究

目的通过高通量测序技术研究重症低龄儿童龋病和健康者唾液的菌群结构及其差异。方法 在青岛市崂山区儿童中,经口腔检查选取健康（H组）和重症低龄龋病（C组）儿童各24名,采取唾液样本,提取其DNA进行聚合酶链式反应扩增,利用454测序平台对16S rRNA V1—V3区进行双端测序,对细菌群落结构及多样性进行差异分析。结果 C组唾液菌群物种丰度高于H组（P<0.05）,两组唾液菌群结构的差异有统计学意义（P<0.01）,且C组的群落结构更为相似和保守（P<0.001）;鉴别出C组高表达的可疑致龋微生物（P<0.1）及H组高表达的健康相关微生物（P<0.1）;基于唾液菌属图谱建立的龋病风险评估模型区分健康和龋病者的准确率可高达70%以上。结论 唾液菌群和特定细菌种类,如比例升高的Prevotella菌属有助于评估和筛选低龄儿童龋病风险。     

Using chlorhexidine varnish to prevent early childhood caries in American Indian children

Objectives: To test the efficacy of 10% chlorhexidine (CHX) dental varnish applied to the mothers' dentition in preventing caries in American Indian children. Methods: This was a placebo‐controlled, double‐blind, randomized clinical trial. Mother–child pairs were enrolled when the child was 4.5‐6.0 months. Mothers received 4 weekly applications of the study treatment (CHX or placebo) followed by single applications when her child was age 12 and 18 months. Children received caries examinations at enrollment, 12, 18 and 24 months. Analyses were limited to the intent‐to‐treat (ITT) group: children whose mothers received the first study treatment and who received at least one post‐baseline exam. The outcome variable was the number of new carious surfaces (NNCS) at the child's last visit. Wilcoxon nonparametric and Fisher's exact tests were used to test differences between the active and placebo groups. Results: We randomized 414 mother–child pairs, with 367 (88.6%) included in the ITT group (active = 188, placebo = 179). The proportion of children caries‐free at their final exam was 51.1% and 50.8% for the active and placebo groups (P > 0.99). The mean NNCS for the active and placebo groups was 3.82 (standard deviation [SD] = 8.18) and 3.80 (SD = 6.08), respectively (P = 0.54). The proportion with NNCS > 6 was 18.1% for active children versus 27.9% for placebo (relative risk [RR] = 0.65, P = 0.03). The number needed to treat to shift one child from NNCS > 6 to a lower severity was 10.2. Conclusions: In this population CHX varnish did not reduce the mean NNCS or proportion of children with caries, but did reduce the proportion with severe caries.     

Dental caries is a preventable infectious disease

Dental caries is the most common infectious disease affecting humans. The principal causative agents are a group of streptococcal species collectively referred to as the mutans streptococci of which Streptococcus mutans and Streptococcus sobrinus are the most important agents of human caries. This review outlines what is currently known about these ubiquitous pathogens and discusses novel methods for elimination of these bacteria from dental plaque.     

Caries prevalence and microbiological and salivary caries activity tests in Scottish adolescents

Salivary and microbiological caries activity tests were investigated on three occasions in a group of 372 Scottish adolescents. Counts of lactobacilli, mutans streptococci, and candida were consistently and significantly associated with caries prevalence, as either DS or DMFS score, and buffering capacity was consistently inversely related to DMFS score. However, veillonella counts and salivary flow rate were not correlated with caries prevalence. Significant improvements in the associations were obtained when the results of more than one test were included using stepwise regression analysis. On an individual basis, at most, stepwise discriminant analysis identified the DMFS group correctly in 49% of all subjects, and the DS group in 47%.     

Response to Seow: Biological mechanisms of early childhood caries

For more than three decades, it has been recognized that dental caries is an infectious and transmissible disease in which diet plays a key role. Nevertheless, in treating patients with early childhood caries, scant attention is placed on exploring the source of infection and the prevalence of caries in other family members. Results from studies conducted in animals clearly show that the virulence of mutans streptococci can be enhanced by a highly cariogenic environment. For example, offspring from a highly caries-active dam develop significantly more caries than pups from a low caries-active dam. Considerable attention has been placed on the role of the nursing bottle in early childhood caries. Milk and some infant formulas do not promote caries and the role of the remainder of the diet has been largely ignored. The nursing bottle can effectively block salivary access to tooth surfaces, thereby increasing the cariogenicity of any food remaining in the mouth. Recent evidence shows that salivary gland function is impaired by iron deficiency and by prenatal exposure to lead. Clearly, early childhood caries is a complex disease that requires careful and extensive investigation.     

Maternal risk indicators for childhood caries in an inner city population

OBJECTIVES: This study evaluated whether characteristics of mothers, such as high mutans streptococci (MS) level, caries experience, reported sugar consumption and demographic variables, could be important risk indicators of caries for their children. METHODS: Mothers selected on the basis of the caries status of their 3-5-year-old-children were tested for MS, caries, reported sugar consumption and demographic variables. RESULTS: We found strong associations between children's caries and their mothers' MS levels (high/low adj. OR = 11.3), maternal active caries (yes/no adj. OR = 4.0) and maternal sugar consumption (high/low adj. OR = 4.2). In this small study, mothers' demographic variables were not associated with the status of caries in their children. CONCLUSIONS: Our findings suggest that maternal high MS levels, maternal active decay and maternal sugar consumption are strong risk indicators for children's caries. Although further study is needed, these three maternal risk indicators, taken together, may prove useful in predicting children's caries risk.     

变形链球菌和放线菌与根面龋关系的研究

目的 :分析变形链球菌和放线菌与根面龋的关系。方法 :用选择性培养基MS和BYS对 30例根面龋中的变形链球菌、放线菌定量研究。结果 :放线菌的检出率 10 0 % ,变形链球菌的检出率 93.33% ,放线菌在数量上 (CFU)占绝对优势 ,与变形链球菌数量相比有高度显著性差异 ,P <0 .0 1。结论 :支持放线菌是根面龋优势菌的观点     

低龄儿童龋治疗时机的选择

目的：评价严重龋损乳磨牙治疗时机选择对儿童牙科畏惧程度和就诊行为的影响。方法：实验组为临床症状明显、主动初诊3～6岁患儿144例。对照组为口腔检查中发现无自觉症状乳磨牙龋病3～6岁患儿144例。用中文改良儿童牙科焦虑面部表情量表（MCDASf）评估患儿初次治疗前、治疗后及1周复诊时的主观畏惧状况;Venham 临床焦虑与合作行为评定量表评估初次就诊时与复诊时患儿临床就诊行为。对数据进行统计学分析。结果：实验组治疗后、复诊时 MCDASf 评分较治疗前均下降（P ＜0．05）。对照组治疗后、复诊时 MCDASf 评分较治疗前无明显变化（P ＞0．05）。实验组患儿治疗前后 MCDASf评分差值大于对照组（P ＜0．05）。复诊时2组患儿 Venham 评分级别一致（P ＞0．05）。实验组患儿就诊行为改善比对照组明显（P ＜0．05）。结论：对低龄儿童严重龋损非急性期患牙即时诊治可缓解牙科畏惧症。