Advances in Dental Research最新文献

A system for Caries Management by Risk Assessment (CAMBRA^®) has been developed in California. The purpose of this article is to summarize the science behind the methodology, the history of the development of CAMBRA, and the outcomes of clinical application. The CAMBRA caries risk assessment (CRA) tool for ages 6 y through adult has been used at the University of California, San Francisco (UCSF), for 14 y, and outcome studies involving thousands of patients have been conducted. Three outcomes assessments, each on different patient cohorts, demonstrated a clear relationship between CAMBRA-CRA risk levels of low, moderate, high, and extreme with cavitation or lesions into dentin (by radiograph) at follow-up. This validated risk prediction tool has been updated with time and is now routinely used at UCSF and in other settings worldwide as part of normal clinical practice. The CAMBRA-CRA tool for 0- to 5-y-olds has demonstrated similar predictive validity and is in routine use. The addition of chemical therapy (antibacterial plus fluoride) to the traditional restorative treatment plan, based on caries risk status, has been shown to reduce the caries increment by about 20% to 38% in high-caries-risk adult patients. The chemical therapy used for high-risk patients is a combination of daily antibacterial therapy (0.12% w/v chlorhexidine gluconate mouth rinse) and twice-daily high-concentration fluoride toothpaste (5,000 ppm F), both for home use. These outcomes assessments provide the evidence to use these CRA tools with confidence. Caries can be managed by adding chemical therapy, based on the assessed caries risk level, coupled with necessary restorative procedures. For high- and extreme-risk patients, a combination of antibacterial and fluoride therapy is necessary. The fluoride therapy must be supplemented by antibacterial therapy to reduce the bacterial challenge, modify the biofilm, and provide prevention rather than continued caries progression.

Randomized control trial (RCT) methodology has compared interventions for the prevention and management of dental caries since the late 1960s. Despite almost 50 years and evidence of significant wastage within the wider biomedical research field, there has been little investigation into what works well and where weaknesses lie. This paper aims to draw attention to areas for improvement within cariology clinical trial methodology by summarizing systematic reviews on interventions and outcomes, and using examples to illustrate some challenges with intervention delivery fidelity, outcome analyses, and intervention co-production. Trial design stage choices are critical to ensure that optimum information is obtained when testing interventions. Intervention choice, outcome choice, and analyses are particularly important, and cariology trials have specific issues associated with them. A systematic search and review of cariology RCTs found 650 RCT reports. Social Network Analysis of interventions revealed a high degree of separation between prevention and management trials, gaps in clinically important comparisons, and a tendency for there to be comparisons within groups; e.g., comparison of interventions within the same, rather than different, levels of invasiveness. Outcomes measured for the same trial reports show: a focus on restoration performance and individual/population caries burden; the growing use of carious lesion activity and economic-related outcomes; and sparse, although an increase in the use of, patient-reported/patient-centered outcomes. Fidelity of adherence to complex interventions can be challenging to measure but is important in interpreting trial findings. Involving target populations in intervention design, delivery, and relating it to the planned rollout, are opportunities to ensure intervention relevance and improved uptake. Outcomes analyses should consider the minimum clinically important differences and outcome relevance measures for the target population. Factors underlying trialists' comparator and outcome choices need to be identified, and there is a need to ensure that a minimum dataset of outcomes allow for combination and comparisons of trial data for systematic review.

A novel silver nanoparticle (AgNP) formulation was developed as a targeted application for the disinfection of carious dentine. Silver nitrate (AgNO₃) was chemically reduced using sodium borohydrate (NaBH₄) in the presence of sodium dodecyl sulfate (SDS) to form micelle aggregate structures containing monodisperse 6.7- to 9.2-nm stabilized AgNPs. AgNPs were characterized by measurement of electrical conductivity and dynamic light scattering, scanning electron microscopy, transmission electron microscopy, and inductively coupled plasma mass spectrometry. Antimicrobial activity of AgNPs was tested against planktonic cultures of representative gram-positive and gram-negative oral bacteria using well diffusion assays on tryptic soy broth media and monoculture biofilms grown with brain heart infusion ± sucrose anaerobically at 37°C on microtiter plates. Biofilm mass was measured by crystal violet assay. Effects were compared to silver diamine fluoride and chlorhexidine (negative controls) and 70% isopropanol (positive control) exposed cultures. In the presence of AgNPs, triplicate testing against Streptococcus gordonii DL1, C219, G102, and ATCC10558 strains; Streptococcus mutans UA159; Streptococcus mitis I18; and Enterococcus faecalis JH22 for planktonic bacteria, the minimum inhibitory concentrations were as low as 7.6 µg mL^-1 and the minimum bacteriocidal concentrations as low as 19.2 µg mL^-1 silver concentration. Microplate readings detecting crystal violet light absorption at 590 nm showed statistically significant differences between AgNP-exposed biofilms and where no antimicrobial agents were used. The presence of sucrose did not influence the sensitivity of any of the bacteria. By preventing in vitro biofilm formation for several Streptococcus spp. and E. faecalis, this AgNP formulation demonstrates potential for clinical application inhibiting biofilms.

Dental caries remains a world-wide disease despite the global distribution of fluoride. It has become apparent that the introduction of significant levels of sugar (fermentable carbohydrate) into the diet has resulted in a change in the biofilm, encouraging acid formation. Further, there has been a shift in the microbiota in the biofilm to a flora that produces acid, and thrives and reproduces in an acidic environment. The management of caries activity under these conditions has focused on brushing to remove the biofilm with fluoride pastes, and high-dose fluoride treatments. Kleinberg, in the 1970s, identified an arginine-containing compound in saliva that several oral biofilm bacterial species metabolize to produce base. Multiple in situ and in vivo studies have been conducted, and have discussed the ability of multiple bacteria to increase the resting pH of the biofilm and even reduce the decrease in pH when the biofilm is challenged with glucose. This shift in resting pH can shift the level of caries formation by the biofilm. Here, we present 8 clinical studies, with different clinical designs, measuring different clinical outcomes, for a diverse, world-wide population. Each of these studies demonstrates reductions in caries formation beyond that seen with fluoride alone and several demonstrate the reversal of early caries lesions. Significant clinical research has been shown that 1.5% arginine combined with fluoride toothpaste has superior anti-caries efficacy to toothpaste containing fluoride alone.

Erythritol belongs chemically to the family of polyols (or sugar alcohols), yet it is metabolized by animals and humans very differently compared to all other polyols. While polyols have been used traditionally (for about 80 y) to replace sugar in sweet foods to reduce demineralization of tooth enamel and to reduce postprandial blood glucose levels, benefits achieved merely through the absence of sugar, emerging evidence shows that erythritol can play a number of functional roles to actively support maintenance of oral and systemic health. Oral health studies revealed that erythritol can reduce dental plaque weight, reduce dental plaque acids, reduce counts of mutans streptococci in saliva and dental plaque, and reduce the risk for dental caries better than sorbitol and xylitol, resulting in fewer tooth restorations by dentist intervention. Systemic health studies have shown that erythritol, unlike other polyols, is readily absorbed from the small intestine, not systemically metabolized, and excreted unchanged within the urine. This metabolic profile renders erythritol to be noncaloric, to have a high gastrointestinal tolerance, and not to increase blood glucose or insulin levels. Published evidence also shows that erythritol can act as an antioxidant and that it may improve endothelial function in people with type 2 diabetes. This article reviews the key research demonstrating erythritol's oral and systemic health functionalities and underlying mechanisms.

Understanding the microbiology of dental caries is not a mere academic exercise; it provides the basis for preventive, diagnostic, and treatment strategies and gives the dentist a theoretical framework to become a better professional. The last years have seen the development of new research methodologies, ranging from high-throughput sequencing or "omics" techniques to new fluorescence microscopy applications and microfluidics, which have allowed the study of the oral microbiome to an unprecedented level of detail. Those studies have provided new insights about oral biofilm formation, biomarkers of caries risk, microbial etiology, appropriate sampling, identification of health-associated bacteria, and new anticaries strategies, among others. Several pitfalls are associated with the new technologies, including a small number of samples per study group, elevated cost, and genus- or species-based analyses that do not take into consideration intraspecies variability. However, the new data strongly suggest that saliva may not be an appropriate sample for etiological studies or for bacterial caries-risk tests, that microbial composition alone may be insufficient to predict caries risk, and that antimicrobial or immunization strategies targeting single species are unlikely to be effective. Strategies directed toward modulation of the oral biofilm, such as pre- and probiotics, emerge as promising new approaches to prevent tooth decay.

The oral microbiome plays a critical role in maintaining oral health. Frequent dietary carbohydrate intake can lead to dysbiosis of the microbial community from overproduction of acid with selection for increases in acidogenic, acid-tolerant bacteria. Knowledge of the caries-associated microbiome is key in planning approaches to reverse the dysbiosis to achieve health. For risk assessment and treatment studies, it would be valuable to establish whether microbial monitoring requires assay of multiple species or whether selected key species would suffice. Early investigations of the oral microbiota relied on culture-based methods to determine the major bacteria in health and disease. Microbial monitoring using gene probes facilitated study of larger populations. DNA probe methods confirmed and expanded the importance of transmission of bacteria from mother to infant and association of preselected species, including mutans streptococci and lactobacilli with caries in larger populations. 16S ribosomal RNA (rRNA) probes confirmed the wide diversity of species in oral and caries microbiomes. Open-ended techniques provide tools for discovery of new species, particularly when strain/clone identification includes gene sequence data. Anaerobic culture highlighted the caries association of Actinomyces and related species. Scardovia wiggsiae, in the Actinomyces/Bifidobacterium family, and several Actinomyces species have the cariogenic traits of acid production and acid tolerance. Next-generation sequencing combined with polymerase chain reaction methods revealed a strong association with mutans streptococci in a high caries population with poor oral hygiene and limited access to care. A population with a lower caries experience generally had lower or no Streptococcus mutans detection but harbored other acidogenic taxa in the microbiome. Study of the microbiome suggests a role for the assay of selected putative cariogenic species in more aggressive diseases. For many populations with caries progression, however, assay of multiple species will likely be warranted to determine the caries profile of the population and/or individuals under study.

Over 1 in 5 dental patients report moderate to severe dental fear. Although the efficacy of cognitive-behavioral treatment (CBT) for dental fear has been examined in over 20 randomized controlled trials-with 2 meta-analyses finding strong average effect sizes ( d > 1)-CBT has received almost no dissemination beyond the specialty clinics that tested it. The challenge, then, is not how to treat dental fear but how to disseminate and implement such an evidence-based treatment in a way that recognizes the rewards and barriers in the US health care system. This mixed-method study investigated the potential of disseminating CBT through care from a mental health provider from within the dental home, a practice known as evidence-based collaborative care (EBCC). Two preadoption studies were conducted with practicing dentists drawn from a self-organized Practice-Based Research Network in the New York City metropolitan area. The first comprised 3 focus groups ( N = 17), and the second involved the administration of a survey ( N = 46). Focus group participants agreed that CBT for dental fear is worthy of consideration but identified several concerns regarding its appeal, feasibility, and application in community dental practices. Survey participants indicated endorsement of factors promoting the use of EBCC as a mechanism for CBT dissemination, with no factors receiving less than 50% support. Taken together, these findings indicate that EBCC may be a useful framework through which an evidence-based treatment for dental fear treatment can be delivered.

The oral microbiome is natural and has a symbiotic relationship with the host by delivering important benefits. In oral health, a dynamic balance is reached between the host, the environment, and the microbiome. However, the frequent intake of sugar and/or reductions in saliva flow results in extended periods of low pH in the biofilm, which disrupts this symbiotic relationship. Such conditions inhibit the growth of beneficial species and drive the selection of bacteria with an acid-producing/acid-tolerating phenotype, thereby increasing the risk of caries (dysbiosis). A more detailed understanding of the interdependencies and interactions that exist among the resident microbiota in dental biofilms, and an increased awareness of the relationship between the host and the oral microbiome, is providing new insights and fresh opportunities to promote symbiosis and prevent dysbiosis. These include modifying the oral microbiome (e.g., with prebiotics and probiotics), manipulating the oral environment to selectively favor the growth of beneficial species, and moderating the growth and metabolism of the biofilm to reduce the likelihood of dysbiosis. Evidence is provided to suggest that the regular provision of interventions that deliver small but relevant benefits, consistently over a prolonged period, can support the maintenance of a symbiotic oral microbiome.