The aim of this review as part of the preparation for a workshop organized by the European Federation of Conservative Dentistry (EFCD) in conjunction with the European Organisation for Caries ...Research (ORCA) was to systematically analyze available evidence of non-, micro- as well as invasive interventions for root caries lesions (RCLs). For each treatment strategy, a separate systematic review was either performed (micro-invasive and choice of restorative material) or updated (non-invasive and excavation technique) each of them following PRISMA guidelines, and if possible meta-analyses were performed. Besides the general advice to improve tooth brushing with fluoride toothpaste main findings for non-invasive interventions in RCLs, the use of dentifrices containing 5,000 ppm F – as well as professionally applied chlorhexidine varnish or silver diamine fluoride seemed to be more efficacious to arrest root caries compared to conventional fluoride toothpaste or placebo respectively. However, this conclusion is based only on a few randomized clinical trials. For micro-invasive treatments, only 2 studies focusing on sealants were available without clear conclusions. A recent review on the comparison of atraumatic restorative treatment compared with conventional treatment concluded that there is insufficient data to clearly rule out if any difference with regard to restoration longevity between both techniques exists. When restoring coventionally, composites performed better than resin-modified and glass ionomer cements. However, all materials showed rather high annual failure rates in the majority of the studies and evidence is based on a low number of prospective studies with a rather high risk of bias.
Background and Aims
The scope of this working group was to review (1) ecological interactions at the dental biofilm in health and disease, (2) the role of microbial communities in the pathogenesis of ...periodontitis and caries, and (3) the innate host response in caries and periodontal diseases.
Results and Conclusions
A health‐associated biofilm includes genera such as Neisseria, Streptococcus, Actinomyces, Veillonella and Granulicatella. Microorganisms associated with both caries and periodontal diseases are metabolically highly specialized and organized as multispecies microbial biofilms. Progression of these diseases involves multiple microbial interactions driven by different stressors. In caries, the exposure of dental biofilms to dietary sugars and their fermentation to organic acids results in increasing proportions of acidogenic and aciduric species. In gingivitis, plaque accumulation at the gingival margin leads to inflammation and increasing proportions of proteolytic and often obligately anaerobic species. The natural mucosal barriers and saliva are the main innate defence mechanisms against soft tissue bacterial invasion. Similarly, enamel and dentin are important hard tissue barriers to the caries process. Given that the present state of knowledge suggests that the aetiologies of caries and periodontal diseases are mutually independent, the elements of innate immunity that appear to contribute to resistance to both are somewhat coincidental.
Introduction
Innate immunity rapidly defends the host against infectious insults. These reactions are of limited specificity and exhaust without providing long‐term protection. Functional fluids and ...effector molecules contribute to the defence against infectious agents, drive the immune response, and direct the cellular players.
Aim
To review the literature and present a summary of current knowledge about the function of tissues, cellular players and soluble mediators of innate immunity relevant to caries and periodontitis.
Methods
Historical and recent literature was critically reviewed based on publications in peer‐reviewed scientific journals.
Results
The innate immune response is vital to resistance against caries and periodontitis and rapidly attempts to protect against infectious agents in the dental hard and soft tissues. Soluble mediators include specialized proteins and lipids. They function to signal to immune and inflammatory cells, provide antimicrobial resistance, and also induce mechanisms for potential repair of damaged tissues.
Conclusions
Far less investigated than adaptive immunity, innate immune responses are an emerging scientific and therapeutic frontier. Soluble mediators of the innate response provide a network of signals to organize the near immediate molecular and cellular response to infection, including direct and immediate antimicrobial activity. Further studies in human disease and animal models are generally needed.
Summary
The majority of commensal oral streptococci are able to generate hydrogen peroxide (H2O2) during aerobic growth, which can diffuse through the cell membrane and inhibit competing species in ...close proximity. Competing H2O2 production is mainly dependent upon the pyruvate oxidase SpxB, and to a lesser extent the lactate oxidase LctO, both of which are important for energy generation in aerobic environments. Several studies point to a broad impact of H2O2 production in the oral environment, including a potential role in biofilm homeostasis, signaling, and interspecies interactions. Here, we summarize the current research regarding oral streptococcal H2O2 generation, resistance mechanisms, and the ecological impact of H2O2 production. We also discuss the potential therapeutic utility of H2O2 for the prevention/treatment of dysbiotic diseases as well as its potential role as a biomarker of oral health.
Aim: To provide recommendations for dental clinicians for the management of dental caries in older adults with special emphasis on root caries lesions. Methods: A consensus workshop followed by a ...Delphi consensus process were conducted with an expert panel nominated by ORCA, EFCD, and DGZ boards. Based on a systematic review of the literature, as well as non-systematic literature search, recommendations for clinicians were developed and consented in a two-stage Delphi process. Results: Demographic and epidemiologic changes will significantly increase the need of management of older adults and root caries in the future. Ageing is associated with a decline of intrinsic capacities and an increased risk of general diseases. As oral and systemic health are linked, bidirectional consequences of diseases and interventions need to be considered. Caries prevention and treatment in older adults must respond to the patient’s individual abilities for self-care and cooperation and often involves the support of caregivers. Systemic interventions may involve dietary counselling, oral hygiene instruction, the use of fluoridated toothpastes, and the stimulation of salivary flow. Local interventions to manage root lesions may comprise local biofilm control, application of highly fluoridated toothpastes or varnishes as well as antimicrobial agents. Restorative treatment is often compromised by the accessibility of such root caries lesions as well as the ability of the senior patient to cooperate. If optimum restorative treatment is impossible or inappropriate, long-term stabilization, e.g., by using glass-ionomer cements, and palliative treatments that aim to maintain oral function as long and as well as possible may be the treatment of choice for the individual.
During oral biofilm development, interspecies interactions drive species distribution and biofilm architecture. To understand what molecular mechanisms determine these interactions, we used ...information gained from recent biogeographical investigations demonstrating an association of corynebacteria with streptococci. We previously reported that Streptococcus sanguinis and Corynebacterium durum have a close relationship through the production of membrane vesicle and fatty acids leading to S. sanguinis chain elongation and overall increased fitness supporting their commensal state. Here we present the molecular mechanisms of this interspecies interaction. Coculture experiments for transcriptomic analysis identified several differentially expressed genes in S. sanguinis. Due to its connection to fatty acid synthesis, we focused on the glycerol-operon. We further explored the differentially expressed type IV pili genes due to their connection to motility and biofilm adhesion. Gene inactivation of the glycerol kinase glpK had a profound impact on the ability of S. sanguinis to metabolize C. durum secreted glycerol and impaired chain elongation important for their interaction. Investigations on the effect of type IV pili revealed a reduction of S. sanguinis twitching motility in the presence of C. durum, which was caused by a decrease in type IV pili abundance on the surface of S. sanguinis as determined by SEM. In conclusion, we identified that the ability to metabolize C. durum produced glycerol is crucial for the interaction of C. durum and S. sanguinis. Reduced twitching motility could lead to a closer interaction of both species, supporting niche development in the oral cavity and potentially shaping symbiotic health-associated biofilm communities.
The aim of this study was to evaluate the cariogenicity of a milk-based drink intended for older adults that was used as part of a governmental initiative in Chile to improve their nutritional ...conditions. This drink contains a high concentration of sugars, which can contribute to root caries development. To test this hypothesis, an experimental biofilm/caries model was used. Dentin slabs were used to grow biofilms of Streptococcus mutans UA159. Slabs/biofilms were exposed 3× per day to bovine milk with different fat content, the milk-based drink, and the milk-based drink supplemented with 10 g of sucrose added per serving. Slabs exposed to 10% sucrose or 0.9% NaCl were used as positive and negative controls, respectively. Biofilms were analyzed for bacterial counts and acidogenicity. Dentin demineralization was estimated by the loss of surface microhardness and integrated mineral loss. Results were compared by analysis of variance and Tukey’s test. The milk-based drink showed higher acidogenicity than milk with its entire (whole) or reduced total fat content (skim). The milk-based drink supplemented with sucrose had similar acidogenicity as the 10% sucrose positive control (p = 0.506). Whole milk exposure elicited lower bacterial counts than the positive control, the milk-based drink, and the milk-based drink supplemented with sucrose (p = 0.002; 0.006 and 0.014 respectively). Although skim milk induced higher demineralization than whole milk, both milk types produced lower demineralization than the milk-based drink. Regarding integrated mineral loss, demineralization induced by the milk-based drink and the milk-based drink supplemented with sucrose was similar to that induced by the positive control and skim milk (p > 0.05). Sugar-containing milk-based drinks used as dietary supplements for older adults may be highly cariogenic and could represent a potential risk for root caries.
This paper provides recommendations for dentists for the treatment of dental caries in children, with an emphasis on early childhood caries (ECC), primary teeth, and occlusal surfaces in permanent ...teeth. A consensus workshop followed by an e-Delphi consensus process was conducted with an expert panel nominated by the European Organization for Caries Research (ORCA) and European Federation of Conservative Dentistry (EFCD)/German Association of Conservative Dentistry (DGZ) boards. Based on 3 systematic reviews and a nonsystematic literature search, recommendations were developed. The caries decline has led to a more polarized disease distribution in children and adolescents along social gradients which should be taken into account when managing the caries process at all levels, such as the individual, the group, or a population. The control or reduction of caries activity is the basis for successful caries management. In children, caries management requires adequate daily oral hygiene and fluoride application via toothpaste, ensured by caregivers, and especially for ECC prevention an emphasis on sugar intake reduction is needed. These noninvasive interventions are also suitable to arrest or control initial or even cavitated dentine caries lesions in the absence of irreversible pulpitis. Fluoride varnish or silver diammine fluoride can be added as supplementary agents. In pits and fissures, composite resin materials can be used as preventive sealants and for defect-oriented minimally invasive restorations. In primary molars, preformed metal crowns are more successful than multisurface fillings, especially in caries-active patients. With persisting high caries activity, multiple lesions, and limited cooperation, caries control should consist of robust measures with high success rates, even including extraction in selected cases. This applies especially to treatments performed under general anesthesia.
Imbalances within the dental biofilm trigger dental caries, currently considered a dysbiosis and the most prevalent noncommunicable disease. There is still a gap in knowledge about the dynamics of ...enamel colonization by bacteria from the dental biofilm in caries. The aim, therefore, was to test whether the sequence of enamel colonization by a typically commensal and a cariogenic species modifies biofilm's cariogenicity. Dual-species biofilms of
and
on saliva-coated enamel slabs were inoculated in different sequences:
followed by
(Sm-Ss),
followed by
(Ss-Sm),
and
inoculated at the same time (Sm=Ss), and the single-species controls
followed by
(Sm-Sm) and
followed by
(Ss-Ss). Biofilms were exposed to 10% sucrose 3 times per day for 5 days, and the slabs/biofilms were retrieved to assess demineralization, viable cells, biomass, proteins, polysaccharides, and H
O
production. Compared with Sm-Sm, primary inoculation with
reduced demineralization (
< 0.05). Both Ss-Sm and Sm=Ss sequences showed reduction in biomass, protein, and polysaccharide content (
< 0.05). The highest
viable count and H
O
production level and the lowest acidogenicity were observed when
colonized enamel before
(
< 0.05). Initial enamel adherence with commensal biofilms seems to induce more intense competition against more typically cariogenic species, reducing cariogenicity.
The concept of caries as an ecological disease implies the understanding of the intricate relationships among the populating microorganisms. Under frequent sugar exposure, some bacteria from the dental biofilm develop pathogenic traits that lead to imbalances (dysbiosis). Depending on which microorganism colonizes the dental surface first, different competition strategies may be developed. Studying the interactions in the entire dental biofilm is not an easy task. In this study, therefore, we modeled the interplay among these microorganisms using a caries-inducing species (
) and a health-associated species (
). Initial enamel adherence with
seems to induce more intense competition against typically caries-inducing species. Besides continuous exposure with sugars, early colonization of the enamel by highly cariogenic species like
appears to be needed to develop caries lesions as well. Promoting early colonization by health-associated bacteria such as
could help to maintain oral health, delaying dysbiosis.
Resulting in a high economic and biological cost, the traditional therapeutic approach to carious lesion management is still largely restorative. Minimally invasive (MI) treatment offers an ...attractive alternative to managing carious lesions in a more conservative and effective manner, resulting in enhanced preservation of tooth structure. The aim of this review was to summarize the evidence behind several MI alternatives for carious lesion management, including the use of sealants, infiltration, atraumatic restorative treatment (ART), and selective carious tissue removal (e.g., indirect pulp capping, stepwise removal, or selective removal to soft dentine). Relevant literature was screened, and articles reporting randomized controlled trials or systematic reviews of strategies to manage non-cavitated or cavitated carious lesions in adults and children were included. Fifty six articles met the inclusion criteria. For non-cavitated lesions, the use of sealants is supported by strong evidence, while the evidence for infiltration of proximal lesions is moderate. For deep cavitated lesions, selective removal to soft dentin and/or stepwise excavation is supported by strong evidence. The use of the ART technique to restore cavitated lesions is also supported by strong evidence as a suitable strategy that has been used extensively in the literature concerning non-dental settings. Preservation of tooth structure through the use of MI treatment for both non-cavitated and cavitated lesions is supported by moderatestrong evidence, which supports the paradigm shift towards routine use of more conservative strategies in the treatment of carious lesions.
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