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Background Salivary gland tumors are a rare and morphologically diverse group of lesions and their frequency is still unknown in several parts of the world. The knowledge of its population characteristics contributes to a better understanding of its etiopathogenesis. Objectives: This study investigated the frequency of salivary gland tumors in a region of southern Brazil and compared these data in a literature review. Material and Methods A retrospective study was conducted of salivary gland tumors diagnosed at two pathology centers from 1995 to 2016. Patient age and gender, tumor site and frequency, histopathological diagnosis, and symptomatology were evaluated. Chi-squared tests were used to assess the associations between variables. To compare our data, we also conducted a literature review of publications in the PubMed and LILACS databases of retrospective studies of salivary gland tumors. Results A total of 124 salivary gland tumor cases was identified, 81 (65.3%) of which were classified as benign and 43 (34.6%) as malignant. Most tumors occurred in the parotid gland (57.2%). Pleomorphic adenoma was the most common tumor (59.6%), followed by adenocarcinoma not otherwise specified (8.8%). The tumors occurred more often in women (54.8%) than in men (45.2%). Malignant tumors were associated with pain in 31.4% of cases (p

The aim of this study was to synthesize, characterize, and evaluate degradation and biocompatibility of poly(lactic-co-glycolic acid) + hydroxyapatite/β-tricalcium phosphate (PLGA+HA/βTCP) scaffolds incorporating simvastatin (SIM) to verify if this biomaterial might be promising for bone tissue engineering. Samples were obtained by the solvent evaporation technique. Biphasic ceramic particles (70% HA, 30% βTCP) were added to PLGA in a ratio of 1:1. Samples with SIM received 1% (m/m) of this medication. Scaffolds were synthesized in a cylindric shape and sterilized by ethylene oxide. For degradation analysis, samples were immersed in phosphate-buffered saline at 37°C under constant stirring for 7, 14, 21, and 28 days. Nondegraded samples were taken as reference. Mass variation, scanning electron microscopy, porosity analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry were performed to evaluate physico-chemical properties. Wettability and cytotoxicity tests were conducted to evaluate the biocompatibility. Microscopic images revealed the presence of macro-, meso-, and micropores in the polymer structure with HA/βTCP particles homogeneously dispersed. Chemical and thermal analyses presented similar results for both PLGA+HA/βTCP and PLGA+HA/βTCP+SIM. The incorporation of simvastatin improved the hydrophilicity of scaffolds. Additionally, PLGA+HA/βTCP and PLGA+HA/βTCP+SIM scaffolds were biocompatible for osteoblasts and mesenchymal stem cells. In summary, PLGA+HA/βTCP scaffolds incorporating simvastatin presented adequate structural, chemical, thermal, and biological properties for bone tissue engineering.

Objective: To investigate the perceptions of dental students on the learning process regarding the dentist-pediatric patient relationship. Material and Methods: A qualitative study with an exploratory approach was conducted involving semi-structured interviews with sixteen dental undergraduate students randomly selected from the thirty-two students in the last semester of the dentistry course. The transcribed interviews were submitted to content analysis. Results: The sample was composed of nine female (56.3%) and seven male (43.7%) students (median age: 23 years). The factors perceived as most influential with regard to learning the dentist-pediatric patient relationship were observations of professors, other dentists or colleagues and the regular practice of dental procedures. While half of the participants considered lectures on the subject satisfactory, the other half reported a need for more instruction on how to deal with specific clinical situations. Most of the participants would like to have learned more about the dentist-pediatric patient relationship. Conclusion: The majority of students recognized that the teaching and learning process regarding the dentist-pediatric patient relationship is not easy. They reported having little counseling on the how to develop this relationship. The students suggested that the dentist-patient relationship should be addressed more during the course through the inclusion of lectures or classes on this issue as well as the demonstration of specific clinical situations.

Objective: Failures in endodontic treatment may occur by several reasons. Endodontic retreatment is an interesting alternative to manage this clinical problem. However, it is not possible to completely remove the root canal filling by any current retreatment technique. The aim of this study was to evaluate the presence of residual root canal filling materials after endodontic re-instrumentation. Material and Methods: Sixty extracted anterior human teeth were prepared by step-back technique with Flexofiles, K-files and Gates-Glidden (GG) burs. Between the use of each file or bur, root canals were irrigated with sodium hypochlorite (NaOCl). Smear layer was removed by irrigation with ethylenediaminetetraacetic acid and NaOCl. After drying with paper points the root canals were randomly divided into 5 groups (n = 12), according to filling material: Resilon cones/Real Seal sealer or gutta-percha cones and Endofill, Sealapex, AH Plus or MTA Fillapex sealers. After one week, root canal fillings were removed using Eucaliptol and K-files. Root canals were re-instrumented with K-files and GG burs sized larger than the first ones. The removal of root canal filling material was analyzed by radiography and scanning electron microscopy (SEM). Statistical analysis was performed using Binary Logistic Regression test (P < 0.05). Results: Radiographic and SEM analysis showed that material from the MTA Fillapex group was better removed than that from Endofill, Sealapex, AH Plus and Real Seal groups. Conclusion: After re-instrumentation, MTA Fillapex group showed less remnants into the root canals than Endofill, Sealapex, AH Plus and Real Seal groups. Residual material was most often found in the apical third.Keywords Dental radiography; Endodontic retreatment; Root canal filling materials; Scanning electron microscopy.

Stem cells (SCs) enabled great advances in differenthealth fields, including Dentistry. Objective: To investigate theknowledge of last year Dentistry undergraduate students regardingSCs and its applications. Material and methods: A questionnairewith open-ended questions was applied to the students, followedby qualitative-quantitative analysis involving the clustering of theanswers. Results: The majority of students (70%) defined SCsadequately, only half of the interviewees (48.8%) were unable toclassify SCs and just 26.2% classified it correctly. On the questionabout SCs from dental tissues, 77.5% reported it was possibleand 70.9% knew which tissues could be used. The main sourceof knowledge was the media (36.4%), followed by the University(26.6%); 88.5% stated that the topic was only addressed in the firstyear of the course. Consequently, only 7.5% reported being capableof answering questions about it. Conclusion: The students are notreceiving enough information about the topic.

Over the past years, studies have described that users of antipsychotics are less likely to develop cancer than the population in general due to cytotoxic properties of this class of drugs on cancer cells. For this reason, Pimozide has been widely studied as a potential anticancer treatment, and satisfactory results in melanoma, central nervous system tumours, osteosarcoma, neuroblastoma, myeloproliferative neoplasms, breast, lung, prostate, ovarian, colorectal, pancreatic, and hepatocellular carcinoma have been showed. Moreover, advantages as clinical use approved by the Food and Drug Administration (FDA), high clinical safety, low side effects, and reasonable price have stimulated the treatment with Pimozide instead of other agents. The action mechanism remains unclear, but three vias associated to cancer stem cell (CSC) hypothesis show that Pimozide: (a) blocks CSC features, as epithelial-to-mesenchymal transition (EMT), through inhibition of Wnt-β/catenin signalling; (b) acts as an inhibitor of signal transducer and activator of transcription (STAT-3 and 5), pathway which is activated and up-regulated in CSCs; (c) inhibits ubiquitine specific protease (USP1) and WD repeat-containing protein 48 (WDR48), that are proteins responsible to inhibit the differentiation and to maintain the cell in an undifferentiated state. Based on this perspective, the aim of this manuscript is to review the antineoplastic role of Pimozide during tumorigenesis and its potential to revert the process of undifferentiation and proliferation of CSC through different vias.

Regenerative endodontic procedure (REP) has been proposed as a new approach to treat immature permanent teeth. However, materials used in REP for root canal disinfection or cervical sealing may induce tooth discoloration. Objectives To assess tooth crown’s color after intracanal treatment with triple antibiotic paste (TAP) or calcium hydroxide (CH); cervical sealing with glass ionomer cement (GIC) or mineral trioxide aggregate (MTA); and bleaching with carbamide peroxide. Material and Methods After pulp removal and color spectrophotometer measurement, 50 bovine incisors were divided into 4 experimental groups and one control (untreated). Experiments were performed in phases (Ph). Ph1: TAP (ciprofloxacin, metronidazole, minocycline), TAPM (ciprofloxacin, metronidazole, amoxicillin), DAP (ciprofloxacin, metronidazole), or CH treatment groups. After 1 and 3 days (d); 1, 2, 3 weeks (w); and 1, 2, 3 and 4 months (m), color was measured and medications were removed. Ph2: GIC or MTA cervical sealing, each using half of the specimens from each group. Color was assessed after 1d, 3d; 1w, 2w, 3w; 1m and 2m. Ph3: Two bleaching sessions, each followed by color measurement. Data were analyzed with ANOVA and post-hoc Holm-Sidak method. Results Ph1: Specimens of TAP group presented higher color alteration (ΔE) mean than those of TAPM group. No significant difference was found among TAP or TAPM and CH, DAP or Control groups. Ph2: cervical sealing materials showed no influence on color alteration. Ph3: Different ΔE means (from different groups), prior to bleaching, became equivalent after one bleaching session. Conclusions TAP induces higher color alteration than TAPM; color alteration increases over time; cervical sealing material has no influence on color alteration; and, dental bleaching was able to recover, at least partially, the tooth crown’s color.

Objective: To estimate the prevalence of unintentional injuries among children attending public preschools of Florianopolis (Santa Catarina, Brazil) and describe their epidemiological characteristics. Materials and Methods: This is a descriptive cross-sectional study conducted with 398 children in 2009 and data were collected through a questionnaire, filled by parents. Statistical analysis was performed, considering a confidence interval of 95%. Results: Among the 398 children included, 275 (69.1% - 95%: 66.8 to 71.4%) suffered unintentional injuries, making a total of 573 cases. The sample comprised 55.5% male children between 13 and 36 months (61.6% - 95% CI: 59.3 to 63.9%) that were affected. Child home was the place where 352 (61.4% - 95% CI: 59.0 to 63.8%) injuries occurred, 372 (64.9% - IC95%: from 59.1 to 73.7%), which were caused by falls, and 342 (59.7% - 95%:57.3 to 62.1%) were considered mild. In 223 (38.9% - 95%: 36.5% -41.3%) cases, the mother accompanied the child at the time of injury. Conclusion: The prevalence of unintentional injuries was high. In the context of prevention, combined actions among health professionals, government and civil society should be proposed based on local research on the topic. In the era of family health care performed by multidisciplinary teams, it is critical that these injuries receive adequate importance by health professionals and attention in public health policies.

Resumen pt: Objeti vo: Identi fi car a ocorrencia de injurias nao intencionais entre criancas de ate 3 anos de idade, que frequentam a Clinica de Bebes da Universida...

Objective: To evaluate the parent's esthetic acceptance of the use of the cariostatic agent diamine silver fluoride in children aged 0 to 3 years treated at ...

Aim The aim of this paper is to present a review and discussion of the current status of stem cell research with regard to tooth generation. Background Stem cells have been isolated from the pulp tissue of both deciduous and permanent teeth as well as from the periodontal ligament. Dental pulp stem cells demonstrate the capacity to form a dentin pulp-like complex in immunocompromised mice. A tooth-like structure was successfully formed, using a heterogeneous mixture of dental enamel epithelium, pulp mesenchymal cells, and scaffolds. Conclusion The scientific community understands the need for more investigations to completely understand the conditions that would best favor the creation of a tooth substitute. Recent gains in the understanding of the molecular regulation of tooth morphogenesis, stem cell biology, and biotechnology offers the opportunity to realize this goal. Clinical Significance These findings, combined with the recent progress in stem cell research and tissue engineering, might allow the development of alternatives for current materials and therapies used to treat tooth tissue loss (e.g., enamel, dentin, pulp), reconstruct dentoalveolar and craniofacial bone defects, and eventually replace an entire tooth. Citation Nedel F, André DA, Oliveira IO, Cordeiro MM, Casagrande L, Tarquinio SBC, Nor JE, Demarco FF. Stem Cells: Therapeutic Potential in Dentistry. J Contemp Dent Pract 2009 July; (10)4:090-096.

Field cancerization involves the lateral spread of premalignant or malignant disease and contributes to the recurrence of head and neck tumors. The overall hypothesis underlying this work is that endothelial cells actively participate in tumor cell invasion by secreting chemokines and creating a chemotactic gradient for tumor cells. Here we demonstrate that conditioned medium from head and neck tumor cells enhance Bcl-2 expression in neovascular endothelial cells. Oral squamous cell carcinoma-3 (OSCC3) and Kaposi's sarcoma (SLK) show enhanced invasiveness when cocultured with pools of human dermal microvascular endothelial cells stably expressing Bcl-2 (HDMEC-Bcl-2), compared to cocultures with empty vector controls (HDMEC-LXSN). Xenografted OSCC3 tumors vascularized with HDMEC-Bcl-2 presented higher local invasion than OSCC3 tumors vascularized with control HDMEC-LXSN. CXCL1 and CXCL8 were upregulated in primary endothelial cells exposed to vascular endothelial growth factor (VEGF), as well as in HDMEC-Bcl-2. Notably, blockade of CXCR2 signaling, but not CXCR1, inhibited OSCC3 and SLK invasion toward endothelial cells. These data demonstrate that CXC chemokines secreted by endothelial cells induce tumor cell invasion and suggest that the process of lateral spread of tumor cells observed in field cancerization is guided by chemotactic signals that originated from endothelial cells.

Literature showed that the interaction of Mineral Trioxide Aggregate (MTA) with dentin in phosphate-buffered saline (PBS) promotes a biomineralization process that leads to the formation of an interfacial layer with mineralized structures at the cement-dentin interface. Thus, we investigated the in vivo biomineralization process promoted by MTA and Ca(OH)² with dentin. Human dentin tubes filled with ProRoot MTA, Ca(OH)² or kept empty were implanted in subcutaneous tissues in the back of mice. After 12h, 1, 3, 7, 15, 30 and 60 days, the dentin tubes were processed for Scanning Electron Microscope (SEM) observations. SEM examination showed the presence of apatite-like clusters on collagen fibrils over the surface of tubes containing the biomaterials. This mineral deposition was more extensive and compact through time. At day 7, a compact layer of apatite was formed. The MTA/Ca(OH)² -dentin interface showed intratubular mineralization as early as 12h post-implantation. MTA and Ca(OH)² in an in vivo environment promoted a biomineralization process with dentin, simultaneously to the acute inflammatory response. MTA triggered an earlier and denser interfacial layer.

Multipotency is a defining characteristic of post-natal stem cells. The human dental pulp contains a small subpopulation of stem cells that exhibit multipotency, as demonstrated by their ability to differentiate into odontoblasts, neural cells, and vascular endothelial cells. These discoveries highlight the fundamental role of stem cells in the biology of the dental pulp and suggest that these cells are uniquely suited for dental pulp tissue-engineering purposes. The availability of experimental approaches specifically designed for studies of the differentiation potential of dental pulp stem cells has played an important role in these discoveries. The objective of this review is to describe the development and characterization of the Tooth Slice/Scaffold Model of Dental Pulp Tissue Engineering. In addition, we discuss the multipotency of dental pulp stem cells, focusing on the differentiation of these cells into functional odontoblasts and into vascular endothelial cells.

The aim of the present study was to evaluate the pattern of fluoride-containing dentifrice use and associated factors in Brazilian preschoolers.A structured questionnaire was answered by parents of 432 children, who were aged 2 to 6 years, from 12 public preschools in Ijuí, South Brazil. Primary outcomes were age of starting fluoride-containing dentifrice use and amount of dentifrice applied to the toothbrush. Poisson regression with robust variance was used to determine the factors associated with the main outcomes.About 75% of the participants were introduced to fluoride-containing dentifrice before the age of 2 years. The current predominant amount of dentifrice used was obtained by transversal (57.7%), followed by longitudinal deposition on the toothbrush (33.6%), corresponding to 0.3 and 0.9 g of dentifrice, respectively. Previous dental visits and maternal education greater than 4 years were associated with the introduction of fluoride-containing dentifrice before 2 years of age. The probability of using dentifrice in amounts higher than the recommendations doubled in children aged 5 and 6 years.Oral health interventions should reinforce the importance of early introduction of fluoride-containing dentifrice, especially in less-educated mothers. Furthermore, the amount of dentifrice should be reduced to maximise the caries-preventive effect while minimising dental fluorosis.

Transformation of small avascular masses of tumor cells into rapidly progressive cancers is triggered by the angiogenic switch, a process that involves vascular endothelial growth factor (VEGF) signaling. We have shown that VEGF enhances the survival and angiogenic potential of endothelial cells by activating the Bcl-2-CXCL8 signaling axis. The purpose of this study was to evaluate the effect of a small-molecule inhibitor of VEGF receptors (PTK/ZK) on the initial stages of head and neck tumor angiogenesis. In vitro, PTK/ZK blocked head and neck tumor cell (OSCC3 or UM-SCC-17B)-induced Bcl-2 and CXCL8 expression in endothelial cells. Oral administration of PTK/ZK decreased xenograft head and neck tumor microvessel density, and inhibited Bcl-2 and CXCL8 expression in tumor-associated endothelial cells. Analysis of these data demonstrates that PTK/ZK blocks downstream targets of VEGF signaling in endothelial cells, and suggests that PTK/ZK may inhibit the angiogenic switch in head and neck tumors. Abbreviations: HDMEC, human dermal microvascular endothelial cells; VEGF, vascular endothelial growth factor; CXCL8, CXC ligand-8; PTK/ZK, PTK787/ZK222584.