Microbial Population Shift and Metabolic Characterization of Silver Diamine Fluoride Treatment Failure on Dental Caries

Abstract

Objectives: The objective of this pilot study was to describe the microbial profiles present in the plaque and saliva of children who continued to develop new carious lesions following treatment with silver diamine fluoride (nonresponders) compared to caries active, caries- free and children with arrested caries following SDF treatment in order to identify potential microbial differences that may relate to a re-incidence of caries. Methods: Saliva and plaque samples from infected and contralateral sites were obtained from twenty children who were either caries free, had active carious lesions, were caries active and received SDF treatment immediately before sampling, or had previously received SDF treatment and developed new caries. In total, 8,057,899 Illumina-generated sequence reads from 60 samples were obtained. Reads were processed using the Quantitative Insights Into Microbial Ecology pipeline. Group differences were assessed using Analysis of Variance Models and Tukey Honest Significant Differences. To identify significant taxa between treatment groups, Linear discriminant analysis Effect Size (LefSe) and Analysis of Differential Abundance Taking Sample Variation Into Account were used. Results: Differential abundant analysis indicated that members of the Lachnospiraceae family were significantly enriched in non-responders and the genus Tannerella and species Granulicatella adiances were also highly abundant in this group. LefSe analysis between non- responders and SDF-treated groups revealed that genera Leptotrichia and Granulicatella were enriched in non-responders. We observed the highest abundance of phosphotransferase system and lowest abundance of lipopolysaccharide synthesis in non-responders. Discussion: The microbiome in dental biofilms is responsible for the progression of dental caries. SDF has been shown to be effective in arresting the progression carious lesions, thought to be related to its antimicrobial properties. Findings suggest that a differential abundance of select microbiota and specific pathway functioning may contribute to a potential failure of silver diamine fluoride to arrest dental caries.

Silver Diamine Fluoride Applications in Dentistry: Review Article

“…and Veillonella parvula are well-known species that are connected directly to DC, when their prevalence increases they cause demineralization of enamel crystals owing to a high concentration of organic acids which drops the PH and causes a disproportion in the balance between the tooth mineral content and oral plaque (2) , with time persistent loss of tooth surface minerals leads to cavity formation in tooth enamel and dentin which if not treated will advance rapidly to pulpal tissues causing infection, pain, and ultimately tooth loss (3,4) . The traditional treatment of DC demands great skill of the clinician, good patient cooperation besides the cost of expensive materials, different restorative equipment, and instrumentation (5) .…”