Added calcium and phosphate in fluoride varnishes no silver bullet for fighting kids’ tooth decay, study finds

In a recent study published in the journal Dr Scientific reportResearchers tested the effects of sodium fluoride varnish containing phosphate and calcium Streptococcus mutans And Lactobacillus fermentum Calculated in noncarried children with and without cavitated lesions and compared the effect of conventional sodium fluoride varnish.

Study: Effect of fluoride varnish on oral bacteria in preschool children with cavitated and non-cavitated carious lesions: a randomized clinical trial.. Image credit: Created with assistance from DALL·E 3

Background

Early childhood caries is highly prevalent in children worldwide, and bacterial growth in dental biofilms is the etiological basis of this multifactorial microbial disease. Additionally, despite considerable emphasis on dental health, millions of children suffer from caries in their primary teeth. Total enamel continuity breaks are graded for severity based on the presence or absence of cavitated lesions. Various studies have examined the role of demineralization in cavitated wound formation, but there is a paucity of longitudinal studies examining how cavitated wounds become cavitated.

Demineralization of tooth enamel occurs when biofilm microorganisms interact with sugars and reduce tooth surface pH and lead to loss of phosphate and calcium ions. Saliva exerts some protective effects because of its antimicrobial properties, mineral ion content, and ability to neutralize pH. But the presence of pathogenic organisms viz L. fermentum And S. Mutans play an important role in the occurrence and development of caries and these microbes are considered risk markers for childhood caries.

About the study

In the current study, researchers compared the effectiveness of sodium fluoride varnish with phosphate and calcium to conventional sodium fluoride varnish. L. fermentum And S. Mutans Preschool children with biofilm and saliva were counted between non-erosion and children with non-cavitated or cavitated lesions. They also used a quantitative real-time polymerase chain reaction (qRT-PCR) method with species-specific primers to accurately quantify pathogenic microbes.

Participants were recruited for the study from non-profit kindergartens in Hong Kong using a random sampling method. They included children ages three to four with no pre-existing medical conditions, long-term medication needs, or special health needs. Those who had undergone any type of antibiotic treatment in the past month or professional fluoride treatment within the previous six months, had primary tooth enamel hypoplasia, were sensitive to any component of the varnish, or were uncooperative during the study were excluded.

Caries was diagnosed by a dentist based on the International Caries Detection and Assessment System II. Children were divided into three groups – those without caries, those with caries but non-cavitated lesions and those with cavitated carious lesions. The intervention initially consisted of eight applications of the selected varnish applied every four months for 24 months, but due to the coronavirus disease 2019 (COVID-19) pandemic-related school closures and safety concerns, this had to be reduced to three to six applications. ..

Saliva and supragingival biofilm samples were collected at baseline and follow-up for deoxyribonucleic acid (DNA) extraction and qRT-PCR analysis. Species-specific oligonucleotide primer pairs were used to quantitate L. fermentum And S. Mutans From all samples, and samples that had cycle threshold (Ct) values ​​below the detection level determined by the DNA standard curve were considered negative.

result

Findings suggested that sodium fluoride varnishes containing calcium and phosphate reduced L. fermentum and did not significantly improve S. mutans numbers.

However, although previous studies have examined the effect of fluoride varnish on biofilms in children with and without caries, they have not clearly examined differences in microbial levels between non-cavitated and cavitated lesions. Three groups of children were examined separately in the present study. It used a precise qRT-PCR technique to quantify the number of bacteria, which sheds more light on the role of the microbiota in the establishment and progression of cases.

Conclusion

In summary, the study compared the effect of conventional sodium fluoride varnish with that of phosphate and calcium. L. fermentum And S. Mutans Enumeration in saliva and biofilm samples of preschool children. The results show that sodium fluoride varnishes with added phosphate and calcium are not significantly different from conventional sodium fluoride varnishes in reducing bacterial growth in biofilms, and this highlights the need for further research to find effective means of controlling early childhood infections.