A Systematic Review and Meta-Analysis of the Relationship Between the Severity of Dental Fluorosis and Fluoride Biomarkers in Endemic Areas.

The intake of high concentrations of fluoride, mainly through drinking water, diet and fluoridated dentifrices, produces fluorosis, which in its early stages is manifested as dental fluorosis (DF). To recognize exposure to fluoride in endemic areas and to evaluate the risk of developing health impairment, the WHO has established several biomarkers that are used to determine systemic fluorine (F-) exposure. Thus, the aim of this study was to conduct a systematic review and meta-analysis of the relationship between the severity of DF and fluoride biomarkers in endemic areas. The protocol of this study was previously registered as CRD42021244974. A digital search was carried out in PubMed/Medline, SpringerLink, Scopus, Cochrane and Google Scholar by employing the keywords "urine", "nails", "hair", "plasma", "saliva" and "dental fluorosis" for the original studies with content associated with F- for the biomarkers and DF. The mean difference was established as the effect measure for the meta-analysis. Seven studies fulfilled the eligibility criteria, among which five assessed urine and two employed nails as fluoride biomarkers. A positive significant difference was found between the biomarkers and the severity of DF (0.27, p < 0.001) and individually for each biomarker (urine: 0.14, p = 0.001; nails: 0.88, p < 0.05). The F- concentration in urine and nails is correlated with the severity of DF, with the most evident differences between healthy individuals and those with mild severity. Both biomarkers are adequate to assess this relationship in endemic areas of fluoride and DF.

Association of Age and Temperamental Traits with Children's Behaviour during Dental Treatment.

During paediatric dental treatment, cooperation by children is essential, and temperament can determine their behaviour style. This study aimed to associate temperamental traits and age with behaviour during paediatric dental treatment. This was an observational and cross-sectional study of patients aged 3-10 years. To determine the temperamental traits, an Emotionality Activity and Sociability Temperament Survey (EAS) was performed with the children's parents. The type of behaviour was determined with Frankl's criteria. The total scores for temperamental traits, means, and standard deviations were obtained. The chi-squared test, one-way ANOVA and Student's t-test were applied. A total of 140 patients, who were 5 ± 2.1 years old, participated in the study. Age was determinant for negative behaviour, with a greater frequency in children ≤5 years old (p < 0.05), and a significant negative correlation between age and behaviour (rho = -0.245, p = 0.001). Patients with higher emotionality and activity presented negative and definitely negative behaviours more frequently (p < 0.01). The values for sociability and shyness were similar for positive or negative behaviours. In conclusion, the temperamental traits of emotionality and activity were more frequent in children with disruptive behaviours; therefore, conducting a survey on temperamental traits can be useful for planning behavioural approaches in paediatric dentistry.

Epithelial-Mesenchymal Transition Associated with Head and Neck Squamous Cell Carcinomas: A Review.

Head and neck squamous cell carcinomas (HNSCCs) are aggressive, recurrent, and metastatic neoplasms with a high occurrence around the world and can lead to death when not treated appropriately. Several molecules and signaling pathways are involved in the malignant conversion process. Epithelial-mesenchymal transition (EMT) has been described in HNSCCs, a major type of aggressive carcinoma. EMT describes the development of epithelial cells into mesenchymal cells, which depends on several molecular interactions and signaling pathways that facilitate mesenchymal conversion. This is related to interactions with the microenvironment of the tumor, hypoxia, growth factors, matrix metalloproteinases, and the presence of viral infections. In this review, we focus on the main molecules related to EMT, their interactions with the tumor microenvironment, plasticity phenomena, epigenetic regulation, hypoxia, inflammation, their relationship with immune cells, and the inhibition of EMT in the context of HNSCCs.

Recent Biomarkers for Monitoring the Systemic Fluoride Levels in Exposed Populations: A Systematic Review.

Fluorides are compounds that can be found in the minerals of soil with volcanic rocks. Different populations are exposed to high levels of fluorides through drinking water that, due to their chronic intake, cause several types of damage to health. Nails and hair, denominated as recent biomarkers, have been employed for monitoring systemic fluoride from long-term exposure to fluorides. The aim of this study was to perform a systematic review of the use of recent biomarkers for monitoring systemic fluoride levels in exposed populations and verify their validity in the measurement of the fluorine (F-) concentration within the body. A digital search was performed in the databases PubMed/Medline, Springer Link, Cochrane, and Scopus of original articles that employed recent biomarkers for monitoring systemic F-. Seventeen articles were included in this analysis; the recorded variables were the F- amount in each assessed biomarker, source of exposure, and total daily fluoride intake (TDFI). TDFI was associated with F- in nails and hair, as well as the exposure through drinking water. In conclusion, recent biomarkers are adequate for monitoring the systemic fluoride levels by evaluating the chronic/subchronic exposure through different sources, mainly drinking water, considering nails better than hair for this purpose.

Current concepts in ameloblastoma-targeted therapies in B-raf proto-oncogene serine/threonine kinase V600E mutation: Systematic review.

BACKGROUND: Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies. Different signaling pathways that participate in the progression of these tumors have been identified. B-raf proto-oncogene serine/threonine kinase (BRAF) is a protein involved in the behavior of ameloblastomas, and it is related to many cell mechanisms. BRAF gene mutations have been identified in ameloblastomas, of which the BRAF V600E (valine substituted by glutamic acid at amino acid 600) mutation has been the most common and can be present concomitantly with other mutations that may be involved in its behavior. Targeted therapies have been used as an alternative in the case of resistance or contraindications to conventional treatments. AIM: To document the presence of BRAF V600E and additional mutations, their behavior, and targeted therapies in these tumors. METHODS: An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE, Cochrane, EMBASE, and SpringerLink using the terms "ameloblastomas", "BRAF V600E", "additional mutations", and "targeted therapies". Ameloblastomas were classified according to WHO guidelines. Inclusion criteria were articles in English, published not more than 10 years ago, and studies with laboratory works related to BRAF V600E. Articles were evaluated by two independent reviewers and retrieved for full-text evaluation. The EBLIP Critical Appraisal Checklist was used to evaluate the quality of the eligible studies. Descriptive statistical analysis was performed. RESULTS: Two independent reviewers, with a substantial concordance indicated by a kappa coefficient of k = 0.76, evaluated a total of 19 articles that were included in this study. The analysis registered 521 conventional ameloblastomas (AM), 81 unicystic ameloblastomas (UA), 13 ameloblastic carcinomas (AC), three metastatic ameloblastomas (MA), and six peripheral ameloblastomas (PA), of which the histopathological type, anatomic location, laboratory tests, expression of BRAF mutation, and additional mutations were registered. The BRAF V600E mutation was found in 297 AM (57%), 63 UA (77.7%), 3 AC (23%), 1 MA (50%), and 5 PA (83.3%). Follicular type predominated with a total of 116 cases (40%), followed by plexiform type with 63 cases (22.1%). Furthermore, both types presented additional mutations, in which alterations in JAK3 P132T, SMARCB1, PIK3CA, CTNNB1, SMO, and BRAF G606E genes were found. Four case reports were found with targeted therapy to BRAF V600E. CONCLUSION: The identification of BRAF V600E and additional mutations as an aid in targeted therapies has been a breakthrough in alternative treatments of ameloblastomas where surgical treatments are contraindicated.

Transición epitelial mesenquimal en carcinomas de células escamosas de cavidad oral relacionado al comportamiento

En la actualidad, a nivel mundial, el carcinoma oral de células escamosas (COCE) es el tumor maligno de aparición más común de la región, el cual representa la sexta entidad principal de cáncer por incidencia, con la aparición de más de 300 000 casos anuales y alrededor de 150 000 muertes.El COCE se caracteriza por su agresividad, alta recurrencia y metástasis linfática y hematógena, además de resistencia al tratamiento y un bajo índice de supervivencia a los 5 años. Un factor que ejerce amplia influencia en la progresión de las células tumorales y el mal pronóstico es el fenómeno de transición epitelial mesenquimal (TEM), el cual se define como la adquisición de características estromales de una célula epitelial, perdiendo su capacidad adhesiva, lo que le permite adoptar un comportamiento agresivo e invasivo.

En la actualidad, a nivel mundial, el carcinoma oral de células escamosas (COCE) es el tumor maligno de aparición más común de la región, el cual representa la sexta entidad principal de cáncer por incidencia, con la aparición de más de 300 000 casos anuales y alrededor de 150 000 muertes.El COCE se caracteriza por su agresividad, alta recurrencia y metástasis linfática y hematógena, además de resistencia al tratamiento y un bajo índice de supervivencia a los 5 años. Un factor que ejerce amplia influencia en la progresión de las células tumorales y el mal pronóstico es el fenómeno de transición epitelial mesenquimal (TEM), el cual se define como la adquisición de características estromales de una célula epitelial, perdiendo su capacidad adhesiva, lo que le permite adoptar un comportamiento agresivo e invasivo.

Molecular Markers of Anticancer Drug Resistance in Head and Neck Squamous Cell Carcinoma: A Literature Review.

This manuscript provides an update to the literature on molecules with roles in tumor resistance therapy in head and neck squamous cell carcinoma (HNSCC). Although significant improvements have been made in the treatment for head and neck squamous cell carcinoma, physicians face yet another challenge-that of preserving oral functions, which involves the use of multidisciplinary therapies, such as multiple chemotherapies (CT) and radiotherapy (RT). Designing personalized therapeutic options requires the study of genes involved in drug resistance. This review provides an overview of the molecules that have been linked to resistance to chemotherapy in HNSCC, including the family of ATP-binding cassette transporters (ABCs), nucleotide excision repair/base excision repair (NER/BER) enzymatic complexes (which act on nonspecific DNA lesions generated by gamma and ultraviolet radiation by cross-linking and forming intra/interchain chemical adducts), cisplatin (a chemotherapeutic agent that causes DNA damage and induces apoptosis, which is a paradox because its effectiveness is based on the integrity of the genes involved in apoptotic signaling pathways), and cetuximab, including a discussion of the genes involved in the cell cycle and the proliferation of possible markers that confer resistance to cetuximab.