Clinicopathologic and immunohistochemical characterization of 14 cases of angioleiomyomas in oral cavity.

BACKGROUND: Angioleiomyoma (ALM) is a benign neoplasm that originates from vascular smooth muscle. It is extremely rare in oral cavity. The objective of this study was to evaluate the clinicopathological and immunohistochemical characteristics of all oral angioleiomyomas registered in a Center of Diagnosis of Oral Diseases from 1959 to 2017. MATERIAL AND METHODS: Slides from 14 cases of ALM stained with hematoxylin and eosin (H&E) were analyzed to confirm the diagnosis. Moreover, an immunohistochemical panel with alpha-smooth muscle actin (alpha-SMA), desmin, AE1/AE3, CD68, S-100, and CD34 antibodies was performed to evaluate semi-quantitatively the positive cells. RESULTS: ALM correspond to 0.08% of all benign oral tumors analyzed during the 57-year period. The mean age of the patients was 45 years with a predilection to males (58%). The most frequently reported site was lips (50%). Microscopic analysis on H&E sections revealed similar pattern in all cases, showing well-circumscribed and encapsulated tumors, characterized by a proliferation of smooth muscle cells and wide vascular spaces of varying sizes. The predominant immuno profiles were: alpha-smooth muscle actin (alpha-SMA) positive (strong immunoreactivity); positive variable pattern for desmin, negative immunoprofile for AE1/AE3, CD68, and S-100. The endothelial cells of vascular spaces were CD34+. CONCLUSIONS: Based on the results, the alpha-SM actin can be elected as a good marker for angioleiomyomas and can help the confirmation of the morphologic diagnosis of this lesion.

Stem cell-based pulp tissue engineering: variables enrolled in translation from the bench to the bedside, a systematic review of literature.

Stem cell-based therapy (SC-BT) is emerging as an alternative for endodontic therapies. The interaction between stem cells and scaffolds plays a crucial role in the generation of a 'friendly cell' microenvironment. The aim of this systematic review was to explore techniques applied to regenerate the pulp-dentine complex tissue using SC-BT. An electronic search into the SciVerse Scopus (SS), ISI Web Science (IWS) and Entrez PubMed (EP) using specific keywords was performed. Specific inclusion and exclusion criteria were predetermined. The search yielded papers, out of which full-text papers were included in the final analyses. Data extraction pooled the results in four main topics: (a) influence of the chemical properties of the scaffolds over cell behaviour; (b) influence of the physical characteristics of scaffolds over cell behaviour; (c) strategies applied to improve the stem cell/scaffold interface; and (d) influence of cue microenvironment on stem cell differentiation towards odontoblast-like cells and pulp-like tissue formation. The relationship between the scaffolds, the environment and the growth factors released from dentine are critical for de novo pulp tissue regeneration. The preconditioning of dentine walls with ethylenediaminetetraacetic acid (EDTA) was imperative for successful pulp-dentine complex regeneration. An analyses of the grouped results revealed that pulp regeneration was an attainable goal.

Odontoblast RNA stability in different temperature-based protocols for tooth storage.

AIM: To evaluate the effect of four tooth storage temperature-based methods on quality of RNA obtained from cells retrieved from human dental pulps and human pre-dentine. METHODOLOGY: RNA was isolated from dental pulp tissue and from cells retrieved by scraping the pre-dentine of freshly extracted human third molars (n = 15) using TRIzol(®) reagent. Teeth were randomly assigned to the following temperature conditions: immediate RNA isolation after tooth extraction, liquid nitrogen (24 h), -80 °C (24 h), 20 °C (24 h) and 4 °C (6 h). RNA integrity was checked by the density of 28S and 18S ribosomal RNA. RT-PCR was used to analyse the expression of odontoblast makers (DSPP, DMP1 and MEPE) and the housekeeping gene GAPDH. RESULTS: All experimental conditions evaluated preserved RNA integrity. The three odontoblastic markers were amplified from the pulp tissue and from the cells associated with pre-dentine. CONCLUSION: The four storage options allowed RNA isolation for RT-PCR analysis. These findings may facilitate the use of clinically derived human dental pulp and odontoblasts for endodontic research.

Comparative analysis of two colorimetric assays in dental pulp cell density.

AIM: To compare and contrast two colorimetric assays used for the measurement of proliferation using two dental pulp cell types: dental pulp stem cells (DPSC) and human dental pulp fibroblasts (HDPF). METHODOLOGY: Dental pulp stem cells or HDPF were seeded at 0.25×10(4) cells per well in 96-well plates. Cell proliferation was evaluated after 24-72h. At the end of the experimental period, the sulforhodamine B (SRB) assay or a water-soluble tetrazolium salt (WST-1) assay was performed. Optical densities were determined in a microplate reader (Genius; TECAN). Data were analysed by Student's t-test (comparison between cell types) and one-way anova followed by Tukey test (time-point intervals). Pearson' correlation tests were performed to compare the two assays for each cell line. RESULTS: Both assays showed that DPSC had higher proliferation rates than HDPF. A positive significant correlation between the two colorimetric assays tested for both cell types DPSC (Pearson's correlation coefficient=0.847; P<0.05) and HDPF (Pearson's correlation coefficient=0.775; P<0.05). CONCLUSION: Both tests demonstrated similar trends of cell proliferation, and thus are both appropriate for the evaluation of DPSC and HDPF. The choice of assay is therefore one of the practical applications. SRB stained plates can be dried and stored so may have utility in laboratories where data may require review or when access to analytical equipment is limited. WST-1 assays have the benefit of both ease and speed and may have utility in laboratories requiring either high throughput or rapid analyses.

Forty cases of acquired oral syphilis and a review of the literature.

The aim of this study was to describe 40 cases of acquired oral syphilis (AOS) and to discuss the distribution of demographic characteristics, clinical features, and differential diagnosis of the disease. A retrospective study was conducted covering a 17-year period at a single institution in southern Brazil. Moreover, a literature review was performed through a search of the PubMed database for articles on AOS published between 1955 and March 2018. Data were analyzed descriptively. The predominant group within the case series was male patients in their twenties. The vast majority of cases (92.5%) were in the secondary stage of the disease. The lips were the most commonly affected site, with greyish-white mucous patches and reddish ulcers. In the literature review, the largest number of reported cases came from North America. Male patients in the third and fourth decades of life were most affected. AOS occurred more commonly as mucous patches and ulcers on the tongue and palate. Similarities regarding the distribution by sex, age, and anatomical location were found in the present study when compared to cases reported elsewhere. Clinicians, oral pathologists, and maxillofacial surgeons should familiarize themselves with the variable spectrum of signs and symptoms of AOS in their clinical practice to improve diagnosis and management.

Association between developmental defects of enamel and dental caries: A systematic review and meta-analysis.

BACKGROUND: Dental caries is the main problem oral health and it is not well established in the literature if the enamel defects are a risk factor for its development. OBJECTIVE: Studies have reported a potential association between developmental defects enamel (DDE) and dental caries occurrence. We investigated the association between DDE and caries in permanent dentition of children and teenagers. DATA SOURCES: A systematic review was carried out using four databases (Pubmed, Web of Science, Embase, and Science Direct), which were searched from their earliest records until December 31, 2014. STUDY SELECTION: Population-based studies assessing differences in dental caries experience according to the presence of enamel defects (and their types) were included. PRISMA guidelines for reporting systematic reviews were followed. Meta-analysis was performed to assess the pooled effect, and meta-regression was carried out to identify heterogeneity sources. From the 2558 initially identified papers, nine studies fulfilled all inclusion criteria after checking the titles, abstracts, references, and complete reading. Seven of them were included in the meta-analysis with random model. RESULTS: A positive association between enamel defects and dental caries was identified; meta-analysis showed that individuals with DDE had higher pooled odds of having dental caries experience [OR 2.21 (95% CI 1.3; 3.54)]. Meta-regression analysis demonstrated that adjustment for sociodemographic factors, countries' socioeconomic status, and bias (quality of studies) explained the high heterogeneity observed. CONCLUSION: A higher chance of dental caries should be expected among individuals with enamel defects.

Diet influenced tooth erosion prevalence in children and adolescents: Results of a meta-analysis and meta-regression.

OBJECTIVE: The aim of the present study was to assess the influence of diet in tooth erosion presence in children and adolescents by meta-analysis and meta-regression. DATA: Two reviewers independently performed the selection process and the quality of studies was assessed. SOURCES: Studies published until May 2014 were identified in electronic databases: Pubmed, EBSHost, Scopus, Science direct, Web of Science and Scielo, using keywords. STUDY SELECTION: Criteria used included: observational studies, tooth erosion and diet, subject age range 8-19 years old, permanent dentition and index. Meta-analysis was performed and in case of heterogeneity a random-effects model was used. Thirteen studies that fulfilled the inclusion criteria were selected. Higher consumption of carbonated drinks (p=0.001) or acid snacks/sweets (p=0.01 and for acid fruit juices (p=0.03)) increased the odds for tooth erosion, while higher intake of milk (p=0.028) and yogurt (p=0.002) reduced the erosion occurrence. Heterogeneity was observed in soft drinks, confectionary and snacks and acidic fruit juices models. Methodological issues regarding the questionnaires administration and the inclusion of other variables, such as food groups and tooth brushing, explained partially the heterogeneity observed. CONCLUSIONS: Some dietary components (carbonated drinks, acid snacks/sweets and natural acidic fruits juice) increased erosion occurrence while milk and yogurt had a protective effect. Methods to assess diet could influence the homogeneity of the studies and should be considered during the study design. CLINICAL SIGNIFICANCE: The method to assess diet should be carefully considered and well conducted as part of the clinical assessment of tooth erosion, since diet could influence the occurrence of tooth erosion.

Oncogenic somatic events in tissue-specific stem cells: a role in cancer recurrence?

Tissue-specific stem cells (TSSCs) are a very unique cell type, with critical and well-defined roles for the homeostasis of high turnover tissues (such as the blood and the skin). Emerging evidence suggests that TSSCs are implicated in malignancies, with several theories being proposed and tested, including many attempts to identify the cells of origin and studies deigned to understand how TSSCs participate in age-related increase in cancer risk. A currently unexplored possibility in this respect is the plausible theory that an oncogenic event that arises at a TSSC would promote tissue replenishment by cells containing these mutations, with progressive propagation of such mutated TSSCs in the niche. Therefore, the effect of a somatic oncogenic event in a single TSSC may have more important implications than previously anticipated, resulting in sustained and progressively higher cancer risk. This model could have important implications for tumor recurrence, since in some cases the underlying cause might be the development of a new tumor originated from daughter cells of the TSSC that suffered the first oncogenic hit, rather than proliferation of residual cancer cells. In this review, we present and discuss approaches for testing the proposed theory of tumorigenesis and cancer risk, as well as practical implications for biomedical research and clinical practice.

The influence of haemostatic agents on healing of healthy human dental pulp tissue capped with calcium hydroxide.

AIM: To investigate the hypothesis that different haemostatic agents could impair the histological response of human pulps capped with calcium hydroxide. METHODOLOGY: Forty-five third molars scheduled for extraction were selected. Class I cavities with pulp exposures were prepared. Three agents were used to control bleeding: 0.9% saline solution (control, n = 14), 5.25% sodium hypochlorite (n = 16) and 2% chlorhexidine digluconate (n = 15). The pulps were dressed with hard-setting calcium hydroxide cement. After 7, 30 or 90 days, teeth were extracted, formalin-fixed and prepared for histochemical techniques. The biological response was categorized using the following criteria: inflammatory response, soft tissue organization, reactionary dentine and reparative dentine. Data were submitted to statistical analysis, using nonparametric Kruskal-Wallis one-way analysis of variance on ranks. Differences amongst groups were detected using Dunn's method. RESULTS: The statistical analysis disclosed that whilst inflammatory response decreased over time, reactionary dentine deposition and reparative dentine formation increased in the latter periods of evaluation (P < 0.05). The three agents had similar performances for all criteria evaluated. The conventional pulp response to calcium hydroxide was observed over time, and complete pulp healing was observed in 88% of the specimens after 90 days. CONCLUSION: The three haemostatic agents did not impair the healing process following pulp exposure and capping with calcium hydroxide at different time intervals investigated.