Reduced salivary flow and colonization by mutans streptococci in children with Down syndrome

Abstract

OBJECTIVES:Although individuals with Down syndrome have considerable oral disease, the prevalence of dental caries in this group is low. The present study aimed to compare known risk factors for dental caries development in children with Down syndrome and a matched population (siblings). In both populations, the number of acidogenic microorganisms, such as mutans streptococci, lactobacilli and Candida species, and the paraffin-stimulated pH, flow rate and IgA concentration in whole saliva were evaluated and compared.METHOD:Saliva was collected, and the caries index was evaluated in 45 sibling pairs aged between 6 and 18 years old. The salivary IgA concentration was determined by immunoturbidimetry. Salivary mutans streptococci, lactobacilli and Candida species were quantified on mitis salivarius agar containing bacitracin and 20% sucrose, rogosa agar supplemented with glacial acetic acid and sabouraud agar supplemented with chloramphenicol, respectively.RESULTS:Down syndrome children had a higher caries-free rate (p<0.05) and lower salivary mutans streptococci counts (p<0.03) compared to their siblings. Similar numbers of lactobacilli and Candida species were found in both groups. Salivary flow rates were 36% lower in Down syndrome children compared to their siblings (p<0.05). The salivary pH did not differ between Down syndrome children and controls. The Down syndrome children had an IgA secretion rate 29% lower than that of their siblings, but this difference was not statistically significant.CONCLUSIONS:In conclusion, the lower number of mutans streptococci in the saliva may be one of the factors contributing to the lower caries rate observed in Down syndrome children, despite evidence of hyposalivation.

Down Sendromlu Çocuklarda Uyku Apne Sendromu Ve Ağiz Di̇ş Sağliği

“…Ağız kuruluğu ve ağız diş sağlığı problemleri arasındaki ilişki yapılan birçok klinik ve laboratuvar çalışmalarında gösterilmiştir. 24,25 Ağız diş sağlığı problemlerden bir diğeri periodontal hastalıklardır. Periodontal hastalık; periodonsiyumu oluşturan dokuların, büyük oranda da gram negatif bakteri ve spiroketlerin etken olduğu kronik bir hastalıktır.…”

Oral Health in Down Syndrome

“…[7,13,14, 31] The differences herein described may be related to the control group used in each study: nonrelated healthy individuals, healthy siblings or other cognitive impaired individuals. The most commonly used indicator of caries experience is an index comprising disease and treatment markers, the DMFT (Decayed, Missing and Filled Teeth).…”

“…[11,12,14] This index should be analysed together with factors such as a diet, frequency of snacking, social status, oral health in close relatives, dental awareness and past dental history. In studies of Areias et al [11,13,14], the controls were sibling-matched, closest in age, in order to reduce the bias of factors like diet, social status and familiar oral health. In relation to DS, a more accurate assessment of caries experience risk is likely to be obtained by also examining the specific morphology.…”

“…[32][33][34] The literature attributes the low prevalence of caries in individuals with DS to factors such as: eruptive pattern (teeth erupt later and so they are exposed to caries' etiological factors for less time); high prevalence of bruxism (flatter occlusal surfaces facilitate self-cleaning and oral hygiene, eliminating food debris that could be adhered to the sulcus and serve as a substrate for oral bacteria) [35]; dental morphology (microdontic teeth and diastema allow an early detection of caries with a simple clinical examination and without a radiological examination); salivary composition and differences in the composition of the microbiota (saliva buffer capacity of the individuals with DS appears to be higher when compared to general population); visit the dentist early in life (these children have several health problems and their parents seem to be easily warned of the oral risk factors). [11,13,14,36,37] Saliva plays a crucial role in the defense against periopathogenic and cariogenic bacteria in the oral cavity and the equilibrium between demineralisation and remineralisation of enamel and dentin. [3,12,38] Consequently, the protective effects of salivary constituents, salivary flow rates and the salivary buffering capacity are essential.…”

“…[8][9][10] On the other hand, a lower prevalence of dental caries appears to be a characteristic of DS populations, although there are some controversial results. [11][12][13][14][15] The Figure 1. In DS, the respiratory dysfunction is among the pathologies that cause most worries and imply serious dysfunction in the individual development, learning ability and sleep capacity, as well as having large family repercussion.…”