Maxim D. Lagerweij

Introduction The Dutch guideline "Oral care for children: prevention and treatment of caries" describes how to prevent, stabilise, or treat caries lesions using minimally invasive methods in children. The objectives of the present study were to 1) evaluate to what extent oral healthcare professionals (OHCPs) in the Netherlands apply preventive and minimally invasive caries management according to the guideline, 2) evaluate their attitudes towards these treatments, and 3) assess differences between OHCPs in general oral health practice and paediatric dentistry. Methods In this cross-sectional survey study, OHCPs completed questions on guideline knowledge, and practice regarding primary (5 items), secondary and tertiary (9 items) caries prevention was asked using a 5-point Likert scale (1 = never, 5 = always). Attitude towards minimally invasive caries treatments was evaluated as sum score over six statements (range 6 [negative] to 30 [positive]). Results Amongst 187 participants (36.7% paediatric dentists; 79.1% female), 134 (71.7%) OHCPs reported being familiar with the guideline content. OHCPs working in paediatric dentistry applied statistically significantly more primary and (partially) secondary and tertiary prevention than OHCPs in general oral health practice. Median score of attitude towards minimally invasive caries treatments was neutral at 17.2 (SD = 2.6). Conclusion The majority of OHCPs in the present study reported being familiar with the guideline. However there is room for improvement in its implementation in practice. OHCPs working in paediatric dentistry reported greater familiarity with the guideline. Generally, OHCPs had a neutral attitude towards preventive caries management.

It has been questioned whether Streptococcus mutans can still be considered the major etiological agent for caries. The main argument is that most evidence has been based on single-species identification. The composition of the oral microbiome was not analyzed. This systemic review aims to assess the prevalence and abundance of S. mutans in caries-active (CA) and caries-free (CF) subjects based on clinical studies in which the microbiome was investigated. Three databases (PubMed, Cochrane, Embase) were searched until May 22, 2023, for eligible publications that included CA and CF subjects and reported the detection of both S. mutans and the oral microbial community, using DNA-based methods. The clinical and microbial outcomes were summarized and further analyzed using a random-effects model. Of 22 eligible studies, 3 were excluded due to the high risk of bias. In the remaining 19 studies, 16 reported the prevalence of S. mutans , 11 reported its relative abundance, and 8 reported both parameters. The prevalence of S. mutans in CA was either similar to ( n = 4) or higher than ( n = 12) the CF group. The reported relative abundance in CA was higher than CF in all 11 studies, although the values varied from 0.001% to 5%. Meta-analysis confirmed the significance of these findings. The summary of microbial community data did not reveal other caries-associated bacterial genera/species than S. mutans . In conclusion, the collected evidence based on microbiome studies suggests a strong association between the prevalence and abundance of S. mutans and caries experience. While the cariogenic role of S. mutans in the oral ecosystem should be recognized, its actual function warrants further exploration.

This study compared the effect of topically applied fluoride products on dentine lesions in an in vitro experiment. Demineralized bovine dentine specimens were treated once with either SDF solution (35,400 ppm F), NaF varnish (22,600 ppm F), TiF4 solution (9,200 ppm F), SnF2 gel (1,000 ppm F), no treatment (control), or preserved as baseline lesions. After the application and subsequent removal of the fluoride products, the specimens were subjected to pH-cycling. Calcium loss and uptake in the de- and remineralization buffers were assessed daily. Fluoride release into the buffers was analyzed on days 1, 2, 3, 5, 8, and 13. After the pH-cycling period, mineral distribution throughout the lesion depth was analyzed using transversal microradiography (TMR). X-ray energy-dispersive spectroscopy (EDS) examined the deposition of silver, titanium, and tin after application of SDF, TiF4, and SnF2, respectively. Overall, calcium loss and uptake analysis in the de- and remineralization buffers revealed that the SDF product was the most effective in inhibiting lesion progression, followed by the TiF4, NaF, and SnF2 products. Fluoride analysis disclosed a steep reduction of the amount of fluoride released into de- and remineralization buffers with time. The fluoride effects on de- and remineralization continued beyond the days that fluoride was released into the buffers. TMR analysis showed significant remineralization in the outer zone of the dentine lesions for all fluoride products, with SDF giving hypermineralization in this zone. In the inner zone, lesions developed in all fluoride groups, with the smallest in the SDF group. EDS showed silver and titanium deposition in depth up to 85 μm and 8 μm, respectively, while no tin deposition was observed. The silver in the dentine lesions did not contribute significantly to the density of the TMR profiles in the SDF group. In conclusion, all topical fluoride products protected the dentine lesions against lesion progression, but at different degrees. SDF showed a superior effect in protection against further demineralization and enhancement of remineralization. This was probably attributed to its fluoride concentration that was the highest among the fluoride products.

The actual contribution of silver in silver diamine fluoride (SDF) towards the anti‐demineralizing effect is unclear. This study compared the effects of single applications of three concentrations of fluoride (4.1%, 1.025%, 0.26% F⁻) in the form of SDF and potassium fluoride (KF) on demineralized dentin in a 15‐day non‐microbial pH‐cycling model. Calcium loss and uptake in de‐ and remineralization buffers were analyzed daily. Fluoride release in both buffers was analyzed on days 1, 2, 3, and 8. The net calcium results of de‐ and remineralization cycles revealed dose‐response protection without significant differences between equal fluoride concentrations of SDF and KF. In the demineralization cycles, all fluoride treatments, except KF 0.26% F⁻, significantly inhibited demineralization, with KF 4.1% F⁻ being the most effective. In the remineralization cycles, remineralization was enhanced in all fluoride concentration groups in a dose‐response manner with no difference between similar fluoride concentrations of SDF and KF. Daily fluoride effects were constant throughout the experiment. Fluoride analysis revealed statistically significant differences in fluoride release between the treatments on day 1 that diminished on days 2 and 3. The non‐microbial model showed no differences between SDF and KF in inhibiting demineralization and enhancing remineralization of dentin lesions.

Introduction: The learning environment (LE) influences students’ behaviour, and predicts academic achievement, satisfaction and success. Measuring students’ perception of the LE provides relevant information for curricular quality assurance. In this study, a LE assessment was used to observe variations in students’ LE perception throughout the curriculum, to illustrate the possible influence that preclinical training (Pt) and clinical training (Ct) have on students’ learning experience.Materials and Methods: All students in the six‐year undergraduate dental programme (n = 849) at the Academic Centre for Dentistry Amsterdam (ACTA) were approached and divided into Pt and Ct groups according to their training phase in the curriculum. The LE was assessed using the Dundee Ready Educational Environment Measure (DREEM), and the results were evaluated using the Statistical Package for the Social Sciences (SPSS) software for distribution (Kolmogorov‐Smirnov normality test), internal reliability (Cronbach's alpha) and comparative analysis (one‐way ANOVA).Results: The questionnaire was completed by 216 (response rate=65%) Pt students and by 379 (response rate=75%) Ct students. With a general DREEM score of 124.3, significantly higher scores were found during Pt (DREEM=133.4) in comparison with the Ct phase of the curriculum (DREEM=119.2). DREEM scores steadily decreased throughout the 6‐year curriculum, with the highest drops in LE perception observed in the second and third years of the programme. Significant differences in all DREEM domains were observed, with lower scores for Ct.Conclusion: Students’ LE perception deteriorates throughout the curriculum, especially within the Pt‐Ct transition, during the second and third years of the programme. An inferior LE perception was observed in every domain of the LE questionnaire within this transition showing a learning experience, which requires an educational intervention. Further research is required to better understand the educational needs of the Pt‐Ct transition at this school.

Sugar is added to food for a multitude of functions: fermentation, preservation, physical and chemical, and also to satisfy the consumer’s preference for sweetness. Unfortunately, sugar consumption is also a main aetiological factor for dental caries. The relationship between sugar and caries was established in the latter half of the 19th century. Many factors influence this relationship: the availability of sugar for bacterial digestion, the presence of acidogenic bacteria in the plaque on teeth, and the ability of fluoride and saliva to counteract bacteria and acids. The importance of the frequency of administering sugars over the amount has been demonstrated in various studies in humans. Through guidelines, world and national health organizations advocate the reduction of sugar consumption to below 10E% (daily dietary energy percentage consumption per capita), but voluntary implementation on an individual basis is difficult for many, and maybe more compulsory strategies that aim to reduce both the amount and frequency of sugar intake are needed.

Introduction: This study investigated the effect of force feedback (FFB) on student performance in a virtual learning environment (VLE) using the Simodont dental trainer (Moog, Nieuw-Vennep, the Netherlands) and evaluated the students' satisfaction with and without FFB. Methods: The Simodont dental trainer, which was used as a VLE, was randomly assigned to 101 first-year dental students with no previous experience in cutting a tooth or working in a VLE with FFB. This study was designed as a crossover study. One half of the students practiced without FFB, whereas one half practiced with FFB. Both groups practiced four sessions lasting 45 minutes on a cross preparation. In the fifth session, test 1 was scheduled. After test 1, the same practicing and testing protocol was followed, although the environment was switched. After test 2, participants filled out a questionnaire. For the statistical analysis, only the questionnaires of the students who participated in both tests were processed. Results: The results of test 1 and test 2 revealed that only students who used FFB were able to pass the tests. The questionnaire outcomes supported the results of both tests; 100% of the students preferred working with FFB. Conclusions: The results suggest that FFB is important for performance in a VLE and essential for satisfaction.

A dysbiotic state is believed to be a key factor in the onset of oral disease. Although oral diseases have been studied for decades, our understanding of oral health, the boundaries of a healthy oral ecosystem and ecological shift toward dysbiosis is still limited. Here, we present the ecobiological heterogeneity of the salivary ecosystem and relations between the salivary microbiome, salivary metabolome and host-related biochemical salivary parameters in 268 healthy adults after overnight fasting. Gender-specific differences in the microbiome and metabolome were observed and were associated with salivary pH and dietary protein intake. Our analysis grouped the individuals into five microbiome and four metabolome-based clusters that significantly related to biochemical parameters of saliva. Low salivary pH and high lysozyme activity were associated with high proportions of streptococcal phylotypes and increased membrane-lipid degradation products. Samples with high salivary pH displayed increased chitinase activity, higher abundance of Veillonella and Prevotella species and higher levels of amino acid fermentation products, suggesting proteolytic adaptation. An over-specialization toward either a proteolytic or a saccharolytic ecotype may indicate a shift toward a dysbiotic state. Their prognostic value and the degree to which these ecotypes are related to increased disease risk remains to be determined.

In the past, epidemiological studies focused on cavitated stages of caries. The arrival of the International Caries Detection and Assessment System (ICDAS) in 2004 allowed for clinical measurements of the initial stages of enamel caries. However, since the introduction, most studies applying the ICDAS still have studied the diseased population. The objective of this cross-sectional observational study was to describe early enamel caries in a large healthy young adult population and determine the relationship with diet and oral hygiene measures. The study population consisted of 268 healthy participants without frank cavitation. The examinations were done visually and radiographically using ICDAS on all tooth surfaces. In total, 8.6% of the surfaces (occlusal > approximal > smooth) had caries, of which 92.0% were confined to enamel (28.5% ICDAS score 1, 54.0% score 2, 8.6% score 3). Thirteen percent of the occlusal and 63% of the approximal caries were found with radiography. Thus, radiography is quintessential for the diagnosis of approximal enamel lesions. We found a positive correlation between enamel caries (ICDAS 1 to 3) and the consumption of mono- and disaccharides and carbohydrates (r = 0.226 and r = 0.188, respectively, both P < 0.01), as well as a negative correlation with alcohol consumption (r = −0.202, P < 0.01). There was also a positive correlation between enamel caries and the energy intake from mono- and disaccharides (sugar kJ, r = 0.206, P < 0.01), which was independent of body mass index. Only 11 participants consumed less than 10% of total energy as sugar kJ, which is the recommended percentage of kJ from free sugar by the World Health Organization. No clear correlation was found with oral hygiene. In conclusion, in this healthy young adult population, caries was found in 97.8% of the subjects, mostly initial enamel caries (ICDAS 1 to 2) in the occlusal surface of molars, and was related with dietary factors.

A selection of commercially available products containing stannous fluoride (SnF2 )/sodium fluoride (NaF), SnF2 /amorphous calcium phosphate (ACP), SnF2 /NaF/ACP, tin (Sn)/fluorine (F)/chitosan were compared with phytosphingosine (PHS) with respect to their anti-erosive properties in vitro. One-hundred and twenty bovine enamel specimens were immersed in the respective product slurries for 2 min, twice daily. The formulations were diluted with either remineralization solution or artificial saliva. After each treatment, an erosive challenge was performed for 10 min, twice daily, using citric acid, pH 3.4. The specimens were stored in remineralization solution or artificial saliva until the next treatment-erosion challenge. After 10 d, tissue loss was determined using profilometry. Enamel softening was determined through surface microhardness measurements. Tissue-loss values (measured in μm and expressed as mean ± SD) for PHS, SnF2 /NaF, SnF2 /ACP, SnF2 /ACP/NaF, and Sn/F/chitosan treatment groups and for the negative-control group, were, respectively, 35.6 ± 2.8, 15.8 ± 1.8, 22.1 ± 2.0, 22.9 ± 1.8, 16.2 ± 1.2, and 51.2 ± 4.4 in the presence of remineralization solution and 31.7 ± 3.3, 15.6 ± 2.9, 16.5 ± 2.7, 16.8 ± 2.1, 13.1 ± 3.0, and 50.7 ± 2.8 in the presence of artificial saliva. There were no significant differences in surface microhardness measurements between the treatment groups. In conclusion, PHS resulted in a significant reduction of tissue loss compared with the negative control, but in comparison, the toothpastes containing Sn(2+) and F(-) ions were significantly more effective compared with PHS.