This study aimed to evaluate dental adhesives containing different concentrations of zinc oxide nanoparticles (ZnO-NPs) for their use in the treatment of dental fluorosis, observe the interaction of the adhesive on healthy enamel surfaces and with mild and moderate fluorosis, measure the adhesive strength and fluorosis, and determine the phosphorus (P) and calcium (Ca) content on these surfaces, as a reference for the potential use of this adhesive with ZnO-NPs for dental fluorosis treatment. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) were used to characterise the ZnO-NPs and analyse the weight percentages of P and Ca in the enamel using X-ray energy dispersive spectroscopy (EDS) and the adhesive strength using a universal mechanical testing machine. FESEM characterisation revealed that the ZnO-NPs were less than 100 nm in size, with quasi-spherical and hexagonal prism shapes. The synthesis of the ZnO-NPs was confirmed by TEM, revealing their hexagonal crystalline structure. The adhesive strength by the universal mechanical testing machine showed that the adhesive with a 3% wt. concentration of ZnO-NPs was better in the three groups of teeth, showing higher adhesive strength in teeth with mild (15.15 MPa) and moderate (12.76 MPa) fluorosis surfaces, and was even higher than that in healthy teeth (9.65 MPa). EDS analysis showed that teeth with mild and moderate fluorosis had the highest weight percentages of P and Ca, but there were no statistically significant differences compared to healthy teeth and teeth treated with adhesives. Lay description: This study focused on testing a new dental adhesive containing small particles called ZnO nanoparticles (ZnO-NPs). This study aimed to demonstrate whether this adhesive with ZnO-NPs could be useful for treating dental fluorosis by improving its adhesion to teeth. One of the first objectives was to determine whether the dental adhesive could adhere better to teeth affected by mild or moderate fluorosis than to healthy teeth by measuring whether the levels of two important elements for healthy teeth, calcium (Ca) and phosphorus (P), were affected by the adhesive. The size and shape of the small particles and teeth with mild or moderate fluorosis were observed using scanning electron microscopy. The nanoparticles were small (< 100 nm) and had specific quasi-spherical and hexagonal prismatic shapes. More damage to the enamel was observed in teeth with mild or moderate fluorosis than in healthy teeth. The adhesive strength test demonstrated that the dental adhesive with 3% ZnO-NPs had the best adhesion on all healthy conditions of teeth. It was particularly effective in teeth with mild or moderate fluorosis. Finally, the evaluation of the levels of P and Ca on the enamel showed that teeth with fluorosis had higher levels of these elements, but using the dental adhesive with ZnO-NPs did not change the levels of these elements significantly because the adhesive avoided greater detachment because of greater adhesion to these surfaces. In conclusion, adding these small particles to dental adhesives could be an option for treating teeth affected by fluorosis. It stuck well and did not affect the levels of the important elements in the teeth.

The relationship between dental fluorosis and alterations in the salivary proteome remains inadequately elucidated. This study aimed to investigate the salivary proteome and fluoride concentrations in urine and drinking water among Thai individuals afflicted with severe dental fluorosis. Thirty-seven Thai schoolchildren, aged 6-16, were stratified based on Thylstrup and Fejerskov fluorosis index scores: 10 with scores ranging from 5 to 9 (SF) and 27 with a score of 0 (NF). Urinary and water fluoride levels were determined using an ion-selective fluoride electrode. Salivary proteomic profiling was conducted via LC-MS/MS, followed by comprehensive bioinformatic analysis. Results revealed significantly elevated urinary fluoride levels in the SF group (p = 0.007), whereas water fluoride levels did not significantly differ between the two cohorts. Both groups exhibited 104 detectable salivary proteins. The NF group demonstrated notable upregulation of LENG9, whereas the SF group displayed upregulation of LDHA, UBA1, S100A9, H4C3, and LCP1, all associated with the CFTR ion channel. Moreover, the NF group uniquely expressed 36 proteins, and Gene Ontology and pathway analyses suggested a link with various aspects of immune defense. In summary, the study hypothesized that the CFTR ion channel might play a predominant role in severe fluorosis and highlighted the depletion of immune-related salivary proteins, suggesting compromised immune defense in severe fluorosis. The utility of urinary fluoride might be a reliable indicator for assessing excessive fluoride exposure.

OBJECTIVE: This study aimed to compare the impact of case-based learning (CBL) versus lecture-based learning (LBL) on dental students\' clinical decision-making regarding DF severity using Visual Analog Scale (VAS) scoring.
METHODS: Eighty first-year graduate dental students were randomly assigned to either the CBL (n = 38) or LBL (n = 42) groups. Both groups received instruction on DF diagnosis, with CBL involving small group sessions analyzing real cases and LBL involving traditional lectures. Effectiveness was assessed by presenting 32 dental fluorosis cases with Thylstrup-Fejerskov Index (TSIF) scores ranging from 0 to 7 through slide presentations to both groups for VAS assessment. Five evaluators of each group randomly selected were asked to repeat the rating 2 weeks later. Statistical analysis included two-way ANOVA for group and gender differences, intra-class correlation coefficient (ICC) for reliability, and Spearman correlation coefficients for validity.
RESULTS: Variations in VAS scores were observed between CBL and LBL groups, with no significant gender impact. Excellent inter- and intra-evaluator agreement was found for VAS scoring in both groups, indicating its reliability. Validation against established indices (such as DI and TSIF) demonstrated strong correlations, with CBL students exhibiting higher correlations.
CONCLUSIONS: CBL enhances students\' clinical decision-making and proficiency in DF diagnosis, as evidenced by more consistent and accurate VAS scoring compared to LBL. These findings highlight the importance of innovative educational strategies in dental curricula, with implications for improving training quality and clinical outcomes.
BACKGROUND: The study was registered at the Clinical Research Center, Hospital of Stomatology, Wuhan University (Registration code: HGGC-036).

Fluoride is a double-edged sword. It was widely used for early caries prevention while excessive intake caused a toxicology effect, affected enamel development, and resulted in dental fluorosis. The study aimed to evaluate the protective effect and mechanism of Epigallocatechin-3-gallate (EGCG) on the apoptosis induced by fluoride in ameloblast-like cells. We observed that NaF triggered apoptotic alterations in cell morphology, excessive NaF arrested cell cycle at the G1, and induced apoptosis by up-regulating Bax and down-regulating Bcl-2. NaF activated the insulin-like growth factor receptor (IGFR), and phosphatidylinositol-3-hydroxylase (p-PI3K), while dose-dependently down-regulating the expression of Forkhead box O1 (FoxO1). EGCG supplements reversed the changes in LS8 morphology, the cell cycle, and apoptosis induced by fluoride. These results indicated that EGCG possesses a protective effect against fluoride toxicity. Furthermore, EGCG suppressed the activation of p-PI3K and the down-regulation of FoxO1 caused by fluoride. Collectively, our findings suggested that EGCG attenuated fluoride-induced apoptosis by inhibiting the PI3K/FoxO1 signaling pathway. EGCG may serve as a new alternative method for dental fluorosis prevention, control, and treatment.

BACKGROUND: Polymorphisms in genes related to enamel formation and mineralization may increase the risk of developmental defects of enamel (DDE).
OBJECTIVE: To evaluate the existing literature on genetic polymorphisms associated with DDE.
METHODS: This systematic review was registered in the PROSPERO (CRD42018115270). The literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and in the gray literature. Observational studies assessing the association between DDE and genetic polymorphism were included. The Newcastle-Ottawa Scale was used to assess the risk of bias.
RESULTS: One thousand one hundred and forty-six articles were identified, and 28 met the inclusion criteria. Five studies presented a low risk of bias. Ninety-two genes related to enamel development, craniofacial patterning morphogenesis, immune response, and hormone transcription/reception were included. Molar-incisor hypomineralization (MIH) and/or hypomineralization of primary second molars (HPSM) were associated with 80 polymorphisms of genes responsible for enamel development, immune response, morphogenesis, and xenobiotic detoxication. A significant association was found between the different clinical manifestations of dental fluorosis (DF) with nine polymorphisms of genes responsible for enamel development, craniofacial development, hormonal transcription/reception, and oxidative stress. Hypoplasia was associated with polymorphisms located in intronic regions.
CONCLUSIONS: MIH, HPSM, DF, and hypoplasia reported as having a complex etiology are significantly associated with genetic polymorphisms of several genes.

BACKGROUND: Dental fluorosis (DF) is caused by excessive exposure to fluoride during odontogenesis and leads to various changes in the development of tooth enamel. Some regions in Mexico are considered endemic fluorosis zones due to the high fluoride content in drinking water. The objective of this study was to perform a systematic review and meta-analysis to identify the association between the concentration of fluoride in drinking water and the severity of dental fluorosis in northern and western Mexico.
METHODS: This protocol was registered in the PROSPERO database (ID: CRD42023401519). The search for information was carried out in the PubMed/Medline, Scopus, SpringerLink, and Google Scholar databases between January 2015 and October 2023. The overall relative risk was calculated using the inverse of variance approach with the random effects method. The RoB 2.0 tool was used to construct risk plots.
RESULTS: Eleven articles were analyzed qualitatively, and most of the included studies presented at least one level of DF severity; six articles were analyzed quantitatively, dividing them into two regions. In North region it was observed a higher prevalence of severe TF cases, corresponding to ≥ TF 5 category (4.78) [3.55, 6.42]. In the West region, most of the included studies presented a higher prevalence of less severe cases, corresponding to ≤ TF 4, in comparison with the North region (0.01) [0.00, 0.52], interpreted as a protective effect.
CONCLUSIONS: The concentrations of fluorides in drinking water are reportedly high in these regions and are directly related to the severity of dental fluorosis experienced by the inhabitants. In the Northern region exists a major concentration of fluoride in drinking water compared with the Western region as well as a prevalence of higher severity cases of dental fluorosis.

UNASSIGNED: Oral health conditions, such as dental caries, periodontal disease, tooth loss, dental fluorosis, dental trauma, and oral cancer, are prevalent in the WHO Eastern Mediterranean Region. However, there has been no systematic review of oral health promotion interventions in the region.
UNASSIGNED: To review existing literature on oral health promotion programmes in the Eastern Mediterranean Region and recommend improvements for the future.
UNASSIGNED: We reviewed on PubMed and Google Scholar 61 articles published in the Eastern Mediterranean Region between 2010 and 2023. Quality assessment of included studies was performed using established criteria. We used the content analysis approach to create appropriate themes from the studies and to document meaningful conclusions about oral health promotion.
UNASSIGNED: Majority of the studies were cross-sectional, a few were randomized controlled, quasi-experimental, longitudinal studies, or reviews. Oral health problems identified included poor oral health knowledge, dental caries, periodontal disease, tooth loss, dental fluorosis, and oral cancer. Although oral disorders were common in most of the countries, very few have implemented oral health promotion programmes.
UNASSIGNED: We recommend prioritization of oral health promotion programmes in the Eastern Mediterranean Region to tackle the diverse oral health challenges. To be effective, such programmes should be region- and context-specific. More studies on oral health promotion are needed in the region.
استعراض منهجي لبرامج تعزيز صحة الفم في إقليم شرق المتوسط.
نجاة عبد ربه اليافعي، بشرى ناز فاطمة جليل، حمد المضاحكة.
UNASSIGNED: تنتشر في إقليم منظمة الصحة العالمية لشرق المتوسط اعتلالات صحة الفم: مثل تسوس الأسنان، ومرض دواعم الأسنان، وفقدان الأسنان، وتسمم الأسنان بالفلور، ورضح الأسنان، وسرطان الفم. ومع ذلك، لم يُُجرَ استعراض منهجي للتدخلات الرامية إلى تعزيز صحة الفم في الإقليم.
UNASSIGNED: هدفت هذه الدراسة الى الاستعراض المنهجي للمؤلفات المتاحة التي تتناول برامج تعزيز صحة الفم في إقليم شرق المتوسط، والتوصية بتحسينات في المستقبل.
UNASSIGNED: استعرضنا على موقع PubMed وموقع 61 Google Scholar مقالة منشورة في إقليم شرق المتوسط بين عامَي 2010 و2023. وأُجريَ تقييم لجودة الدراسات المشمولة باستخدام معايير مُقرَّرة. واستخدمنا نهج تحليل المحتوى لإعداد مواضيع مناسبة مستمدة من الدراسات وتوثيق استنتاجات هادفة بشأن تعزيز صحة الفم.
UNASSIGNED: كانت غالبية الدراسات مقطعية، وكان قليل منها دراسات مضبوطة ذات عيِّنات عشوائية، أو دراسات شبه تجريبية، أو دراسات طولانية، أو مراجعات. وشملت مشكلات صحة الفم المرصودة: ضعف المعرفة بصحة الفم، وتسوس الأسنان، وأمراض اللثة، وفقدان الأسنان، وتسمم الأسنان بالفلور، وسرطان الفم. ورغم شيوع الاضطرابات الفموية في معظم البلدان، فإن عددًا قليلًًا جدًّا من تلك البلدان نفَّذ برامج لتعزيز صحة الفم.
UNASSIGNED: نوصي بإعطاء الأولوية لبرامج تعزيز صحة الفم في إقليم شرق المتوسط للتصدي للتحديات المتنوعة المتعلقة بصحة الفم. ولتكون هذه البرامج فعالة، ينبغي أن تكون محدَّدة المناطق والسياق. وتدعو الحاجة إلى مزيد من الدراسات عن تعزيز صحة الفم في الإقليم.
Revue des programmes de promotion de la santé bucco-dentaire dans la Région de la Méditerranée orientale.
UNASSIGNED: Les affections bucco-dentaires, telles que les caries dentaires, les parodontopathies, la perte de dents, la fluorose dentaire, les traumatismes dentaires et le cancer de la bouche, sont prévalentes dans la Région OMS de la Méditerranée orientale. Cependant, aucune revue systématique des interventions de promotion de la santé bucco-dentaire n\'a été effectuée dans la Région.
UNASSIGNED: Examiner la littérature existante sur les programmes de promotion de la santé bucco-dentaire dans la Région de la Méditerranée orientale et recommander des améliorations pour l\'avenir.
UNASSIGNED: Nous avons passé en revue 61 articles publiés sur PubMed et Google Scholar dans la Région de la Méditerranée orientale entre 2010 et 2023. L\'évaluation de la qualité des études incluses a été effectuée à l\'aide des critères établis. Nous avons utilisé l\'approche d\'analyse de contenu pour créer des thèmes appropriés à partir des études et pour documenter des conclusions significatives sur la promotion de la santé bucco-dentaire.
UNASSIGNED: La majorité des études étaient transversales, quelques-unes étaient des études contrôlées randomisées, quasi-expérimentales, longitudinales ou des analyses. Parmi les problèmes de santé bucco-dentaire recensés figuraient les connaissances insuffisantes dans ce domaine, les caries dentaires, les parodontopathies, la perte de dents, la fluorose dentaire et le cancer de la cavité buccale. Bien que les troubles bucco-dentaires soient courants dans la plupart des pays, très peu de pays ont mis en œuvre des programmes de promotion de la santé bucco-dentaire.
UNASSIGNED: Nous recommandons de prioriser les programmes de promotion de la santé bucco-dentaire dans la Région de la Méditerranée orientale afin de s\'attaquer aux différents défis dans ce domaine. Pour être efficaces, ces programmes doivent être spécifiques à la Région et au contexte. D\'autres études sur la promotion de la santé bucco-dentaire sont nécessaires dans la Région.

OBJECTIVE: Correct identification and management of Developmental Defects of Enamel (DDEs) are essential to provide the best possible treatment. The present survey aims to investigate Italian dentists\' knowledge of DDEs, their ability to recognise the different clinical pictures, and to choose the most appropriate clinical approach.
METHODS: A cross-sectional survey was planned based on a questionnaire including 27 closed-ended questions, and that proposed 4 clinical pictures, molar incisor hypomineralisation (MIH), amelogenesis imperfecta (AI), dental fluorosis (DF), and an initial caries lesion (ICL). It was distributed by e-mail to all Italian dentists (N = 63,883) through the Italian Federation of Doctors and Dentists. Discrete variables were expressed as absolute and relative frequencies (%). A multivariate analysis assessed whether socio-demographic variables correlated with the answers\' truthfulness.
RESULTS: About 5017 questionnaires were included and analysed. Although 90.19% of the sample stated that they had received information on DDEs, a significant percentage did not recognise MIH (36.36%), AI (48.34%), DF (71.50%), and ICL (46.62%). Only 57.07% correctly classified enamel hypomineralisation as a qualitative defect, and even fewer, 54.45%, classified enamel hypoplasia as a quantitative defect. According to the logistic regressions, female dentists, dentists who treat mainly children and received information about DDEs, were more likely to recognise the 4 clinical pictures (P < .01).
CONCLUSIONS: Italian dentists showed many knowledge gaps on DDEs that need to be filled; those who received formal training were more capable of correctly identifying the defects and were more likely to prescribe an appropriate management approach for the defects.
CONCLUSIONS: Increasing university courses and continuing education on diagnosing and managing DDEs seems reasonable to fill the knowledge gap on DDEs.

BACKGROUND: Dental fluorosis is a discoloration of the teeth caused by the excessive consumption of fluoride. It represents a distinct manifestation of chronic fluorosis in dental tissues, exerting adverse effects on the human body, particularly on teeth. The transmembrane protein 16a (TMEM16A) is expressed at the junction of the endoplasmic reticulum and the plasma membrane. Alterations in its channel activity can disrupt endoplasmic reticulum calcium homeostasis and intracellular calcium ion concentration, thereby inducing endoplasmic reticulum stress (ERS). This study aims to investigate the influence of calcium supplements and TMEM16A on ERS in dental fluorosis.
METHODS: C57BL/6 mice exhibiting dental fluorosis were subjected to an eight-week treatment with varying calcium concentrations: low (0.071%), medium (0.79%), and high (6.61%). Various assays, including Hematoxylin and Eosin (HE) staining, immunohistochemistry, real-time fluorescence quantitative polymerase chain reaction (qPCR), and Western blot, were employed to assess the impact of calcium supplements on fluoride content, ameloblast morphology, TMEM16A expression, and endoplasmic reticulum stress-related proteins (calreticulin (CRT), glucose-regulated protein 78 (GRP78), inositol requiring kinase 1α (IRE1α), PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6)) in the incisors of mice affected by dental fluorosis. Furthermore, mice with dental fluorosis were treated with the TMEM16A inhibitor T16Ainh-A01 along with a medium-dose calcium to investigate the influence of TMEM16A on fluoride content, ameloblast morphology, and endoplasmic reticulum stress-related proteins in the context of mouse incisor fluorosis.
RESULTS: In comparison to the model mice, the fluoride content in incisors significantly decreased following calcium supplements (p < 0.01). Moreover, the expression of TMEM16A, CRT, GRP78, IRE1α, PERK, and ATF6 were also exhibited a substantial reduction (p < 0.01), with the most pronounced effect observed in the medium-dose calcium group. Additionally, the fluoride content (p < 0.05) and the expression of CRT, GRP78, IRE1α, PERK, and ATF6 (p < 0.01) were further diminished following concurrent treatment with the TMEM16A inhibitor T16Ainh-A01 and a medium dose of calcium.
CONCLUSIONS: The supplementation of calcium or the inhibition of TMEM16A expression appears to mitigate the detrimental effects of fluorosis by suppressing endoplasmic reticulum stress. These findings hold implications for identifying potential therapeutic targets in addressing dental fluorosis.

As a safe, effective, economical, and convenient technique, tooth whitening is one of the most popular treatments for improving tooth discoloration. This review summarizes the theoretical and recent research developments in the classification and mechanisms of tooth discoloration, as well as the principles, agents, effects, and side effects of tooth whitening techniques. The aim is to provide a basis for the clinical treatment of tooth whitening techniques and to suggest possible new ideas for further research. The accepted mechanism of whitening is the redox reaction of oxides in the whitening reagent, and the whitening effect is remarkable. However, side effects such as tooth sensitivity and irritation of gum and other oral soft tissues can still occur. It is recommended that more monitoring be carried out in the clinic to monitor these side effects, and care should be taken to protect the soft tissues in the mouth during office whitening procedures. Furthermore, there is a need to develop new additives or natural whitening products to reduce the occurrence of side effects.