Poly(methyl methacrylate) (PMMA) is a widely used polymer for dental applications, and it is mainly used in the fabrication of dental prostheses. In an increasing number of these applications, the risk of suffering bacterial or fungal infection is higher than 60% among oral-prosthesis users. Some authors have reported the failure of other implants in the human body due to biofilm formation on the surface (mainly for total hip implants). In the dental field, the formation of bacterial and fungal biofilms on prosthesis’s surface is the etiologic factor for stomatitis, mainly caused by Candida albicans and bacteria such as Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis, as well as many others. The antibacterial and antifungal properties of silver nanoparticles (AgNPs) have been widely reported, and their use in dental materials can prevent oral infections, such as candidiasis and stomatitis, and promote better oral health in dental-prosthesis users. They can even be used in other biomedical applications that require controlling biofilm formation on surfaces. In this review, the reported studies that use composites of PMMA and AgNPs (PMMA-AgNPs) for dental applications are listed and checked, with the aim of gaining a wider perspective of the use and application of this approach in the dental field.

The aim of this study was to evaluate the biocompatibility of the regeneration of the dentin–pulp complex in a murine model with different treatments with MTA Angelus, NeoMTA, and TheraCal PT. An in vivo controlled experimental study of 15 male Wistar rats forming three study groups, the upper and lower central incisors were selected where pulpotomies were conducted, leaving a central incisor as control at 15, 30, and 45 days. For data analysis, these were expressed as mean ± standard deviation and were examined by Kruskal–Wallis test. Three factors were analyzed as follows: “inflammatory infiltrate; disorganization of pulp tissue, and the formation of reparative dentin”. No statistical significance was found between the different groups (p > 0.05). Treatment with these three biomaterials (MTA, TheraCal PT, and Neo MTA) presented an inflammatory infiltrate and slight disorganization of the odontoblast layer in the pulp tissue of a murine model, with normal coronary pulp tissue and the formation of reparative dentin in the three experimental groups. Thus, we are able to conclude that all three are biocompatible materials.

Rhabdomyosarcoma (RMS) is a soft tissue malignant tumor of mesenchymal cell origin, which usually shows variable differentiation of muscle cells. It is the most common solid sarcoma in children. The most usual site of occurrence are the head and neck regions. RMS presents a variety of histologic features, and so differential diagnosis with other small round cell tumors is needed. Hence, it has been very useful to the field to undertake additional immunohistochemical studies to determine the diagnosis and, on occasions, to assign subtype tumors. A systematic review of three databases (Medline, Biological Science Collection and Health & Medical Collection) was carried out with the purpose of analyzing rhabdomyosarcoma cases reported in the literature, specifically with localization in the head and neck regions in children. This strategy allowed us to identify the main anatomical site of appearance, the subtype of RMS, average age, histologic characteristics and immunohistochemistry markers used in a usual and any additional way. According to the selection criteria in this systematic review, twelve articles, and fourteen cases were identified that highlight that the histological diagnosis usually presents cellular heterogeneity. Therefore, immunohistochemistry is needed to confirm the diagnosis. Histologic characterization is not always sufficient for a conclusive diagnosis of RMS. Therefore, immunohistochemistry is helpful to determine the subtype and consequently, sometimes the behavior, treatment and prognosis. Additional markers may vary according to the institution and the need of particular cases. Key words:Pediatric, rhabdomyosarcoma, head and neck, histologic, immunohistochemistry.

Cell proliferation and invasion are characteristic of many tumors, including ameloblastoma, and are important features to target in possible future therapeutic applications. Objective: The objective of this study was the identification of key genes and inhibitory drugs related to the cell proliferation and invasion of ameloblastoma using bioinformatic analysis. Methods: The H10KA_07_38 gene profile database was analyzed by Rstudio and ShinyGO Gene Ontology enrichment. String, Cytoscape-MCODE, and Kaplan–Meier plots were generated, which were subsequently validated by RT-qPCR relative expression and immunoexpression analyses. To propose specific inhibitory drugs, a bioinformatic search using Drug Gene Budger and DrugBank was performed. Results: A total of 204 significantly upregulated genes were identified. Gene ontology enrichment analysis identified four pathways related to cell proliferation and cell invasion. A total of 37 genes were involved in these pathways, and 11 genes showed an MCODE score of ≥0.4; however, only SLC6A3, SOX10, and LRP5 were negatively associated with overall survival (HR = 1.49 (p = 0.0072), HR = 1.55 (p = 0.0018), and HR = 1.38 (p = 0.025), respectively). The RT-qPCR results confirmed the significant differences in expression, with overexpression of >2 for SLC6A3 and SOX10. The immunoexpression analysis indicated positive LRP5 and SLC6A3 expression. The inhibitory drugs bioinformatically obtained for the above three genes were parthenolide and vorinostat. Conclusions: We identify LRP5, SLC6A3, and SOX10 as potentially important genes related to cell proliferation and invasion in the pathogenesis of ameloblastomas, along with both parthenolide and vorinostat as inhibitory drugs that could be further investigated for the development of novel therapeutic approaches against ameloblastoma.

Background: Oral lichen planus is a chronic inflammatory skin disease of autoimmune nature, with infiltration of T lymphocytes that destroy the basal stratum, which causes white striae, erosions, ulcers and breaks in epithelial continuity.Case report: 54-year-old woman with multiple reticular and erosive lesions in the region of the buccal mucosa and lateral borders of the tongue, as well as desquamative gingivitis. Treatment with mometasone was started thrice daily for 20 days and intermittently with miconazole gel to prevent iatrogenic mycosis by the corticosteroid. The patient was examined at 20 days, after which 80 % improvement of the lesions that had central ulcerations was observed, which allowed the ingestion of food and fluids without pain and improved the quality of life.Conclusions: In autoimmune diseases, clinical-histopathological correlation is important for a definitive diagnosis to be established. Clinical follow-up of these patients should be carried out in the long term, in order to achieve remission of the lesions, control of the disease and avoid future complications.