Relationship between the salivary concentration of matrix metalloproteinases 8 and 20 and severe early childhood caries.

BACKGROUND: Dental caries is initiated through mineral dissolution by bacterial acids and collagen degradation by endogenous proteolytic enzymes, mainly collagenolytic matrix metalloproteinases (MMPs). OBJECTIVES: The present research aimed to evaluate the relationship between severe early childhood caries (S-ECC) and salivary MMP-8 and MMP-20 concentrations. MATERIAL AND METHODS: Fifty children aged 36-60 months were assigned to either the caries-free (control) group or the S-ECC group. Standard clinical examinations were performed, and approx. 1 mL of expectorated unstimulated whole saliva was collected from all participants. In the S-ECC group, the sampling was repeated 3 months after restorative treatment. All samples were analyzed for the salivary concentrations of MMP-8 and MMP-20, using the enzyme-linked immunosorbent assay (ELISA). Statistical analysis employed the t test, the Mann-Whitney U test, the χ2 test, Fisher's exact test, and the paired samples t test. The level of significance was set at 0.05. RESULTS: At baseline, the subjects in the S-ECC group presented with significantly elevated levels of MMP-8 as compared to the control group. However, the salivary concentration of MMP-20 did not exhibit a significant difference between the 2 groups. A significant reduction occurred in the levels of MMP-8 and MMP-20 3 months after restorative treatment in the S-ECC group. CONCLUSIONS: The salivary levels of MMP-8 and MMP-20 were significantly affected by dental restorative treatment in children. Furthermore, MMP-8 was observed to be a better indicator of the dental caries status than MMP-20.

How to use mixed methods in oral health research.

Wicked problems exist in the realm of oral health research. Due to their inherent complexity, using qualitative or quantitative methods alone may not be adequate for resolving them. Mixed methods approaches combine qualitative and quantitative methods, and thus, can provide a powerful tool for understanding and solving complex problems in dental public health. However, using mixed methods does not come without its challenges. This commentary outlines four main tips for researchers to consider when applying mixed methods to their research projects.

Evaluation of the flexural strength of orthodontic acrylic resin incorporated with propolis nanoparticles: an in vitro study.

AIM: Nanopropolis has become the subject of interest in medicine and dentistry as a natural product due to its outstanding properties, particularly antimicrobial activity. This study aimed at investigating the effect of nanopropolis on flexural strength of polymethyl methacrylate (PMMA).

Advancing a programme theory for community-level oral health promotion programmes for humanitarian migrants: a realist review protocol.

INTRODUCTION: Humanitarian migrants often suffer from poor health, including oral health. Reasons for their oral health conditions include difficult migration trajectories, poor nutrition and limited financial resources. Oral health promotion is crucial for improving oral health-related quality of life of humanitarian migrants. While community-level oral health promotion programmes for humanitarian migrants have been implemented (eg, in host countries and refugee camps), there is scant literature evaluating their transferability or effectiveness. Given that these programmes yield unique context-specific outcomes, the purpose of this study is to understand how community-level oral health promotion programmes for humanitarian migrants work, in which contexts and why. METHODS AND ANALYSIS: Realist review, a theory-driven literature review methodology, incorporates a causal heuristic called context-mechanism-outcome configurations to explain how programmes work, for whom, and under which conditions. Using Pawson's five steps of realist review (clarifying scope and drafting an initial programme theory; identifying relevant studies; quality appraisal and data extraction; data synthesis; and dissemination of findings), we begin by developing an initial programme theory using the references of a scoping review on the oral health of refugees and asylum seekers and through hand searching in Google Scholar. Following stakeholder validation of our initial programme theory, we will locate additional evidence by searching in four databases (Ovid Medline, Ovid Embase, Cochrane Library and Cumulative Index to Nursing and Allied Health Literature (CINAHL)) to test and refine our initial programme theory into a middle-range realist programme theory. The resultant theory will explain how community-level oral health promotion programmes for humanitarian migrants work, for whom, in which contexts and why. ETHICS AND DISSEMINATION: Since this study is a review and no primary data collection will be involved, institutional ethics approval is not required. The findings of this study will be disseminated in peer-reviewed journals, local and international conferences, and via social media. TRIAL REGISTRATION NUMBER: CRD42021226085.

In Vitro Effects of Three Fluoride-Free Pastes on Remineralization of Initial Enamel Carious Lesions.

Purpose: The purpose of this study was to compare the efficacy of nanohydroxyapatite (NHA), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and calcium sodium phosphosilicate (NovaMin®) in remineralization of early enamel lesions and compare enamel surface changes using a scanning electron microscope (SEM). Methods: Thirty human premolars were sectioned into halves and randomly assigned to five groups (control, demineralization, NHA, CPP-ACP, NovaMin®; n equals 12). Ten samples in each of the three test groups were demineralized and treated with their designated paste for two minutes in 24-hour intervals for 30 days. They were subjected to the Vickers microhardness test on days 15 and 30, and their microhardness values were compared to the control and demineralization groups. The remaining two samples of each group were observed through SEM. Analysis of variance, Tukey's test, and paired t-tests were applied at P<0.05. Results: On day 15, a significant increase in surface microhardness compared to the control was only observed in the CPP-ACP group (P<0.05). Microhardness scores of all paste groups significantly increased between days 15 and 30 (P<0.001), while no significant differences were observed between them on day 30. In SEM images of all test groups, surface integrity increased, although NHA-treated samples had the most homogenous surface. Conclusion: Since all three pastes significantly remineralized incipient enamel lesions, they are potentially qualified for caries prevention.

Adenoid cystic carcinoma of buccal mucosa: A report of two rare cases and review of literature.

In the oral cavity, adenoid cystic carcinomas of the buccal mucosa are extremely rare. Minor salivary grand adenoid cystic carcinoma should receive aggressive treatment to achieve negative surgical margins to inhibit recurrence.