Detection of mast cells in ameloblastomas and odontogenic keratocysts

MCs (MCs) have been ascribed to mediating several diseases, including malignant neoplasms. These cells can play a role in angiogenesis, tissue remodeling and immune modulation and favor neoplasm progression. Despite the studies analyzing the contribution of MCs in odontogenic lesions, its biological behavior in ameloblastomas (AMBs) and odontogenic keratocysts (OKCs) remains unclear. This study aims to detect MCs in OKCs and AMBs and clarify the role of MCs in these lesions. A total of 40 odontogenic lesions were analyzed. This included 20 OKCs and 20 AMBs, 10 being the solid type and the other 10 being the unicystic type of AMB. All cases were histologically reviewed in hematoxylin-eosin. Clinical data, such as age, gender, location, size, radiographic presentation and, histologic patterns were collected from the clinical charts. The Mann?Whitney U test (MWU) was used verify the hypothesis, through inferential statistics. The level of significance used in the statistical test was 0.5%. MCs were observed in 60% of OKCs, and 35% of AMBs. The ratio of MCs observed in OKCs was 0.37, 0.48 in solid AMBs and 0.01 in unicystic AMBs. There was no significant difference between number of MCs in AMBs and OKCs, however, a significant difference was observed between solid and unicystic AMBs (p ? 0.01). MCs may play an important role in the biological behavior of AMBs and OKCs. However, in this study it was not possible to confirm the contribution of MCs in the biological behavior of these lesions and more studies are needed to clarify this relation

Citotoxicity evaluation of three dental adhesives on vero cells in vitro

To evaluate, in vitro, the potential cytotoxicity of three different dental adhesives systems (Adper Single Bond 2 -SB, Silorane System Adhesive Bond -SSAB and Single Bond Universal -SBU) on cultivated Vero cells after different contact times. The cells were cultured in a concentration of 2 x 105 cells/mL for 24h and grown to sub-confluent monolayers. VERO cells were exposed to 25µl of conditioned extracts obtained from 24h, 48h and 72h immersion of adhesive samples in culture medium (DMEM), immediately after polymerization. Fresh DMEM was used as negative control. Cell metabolism was evaluated by the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2, 5diphenyl-tetrazolium bromide). The data were analyzed statistically by ANOVA, considering a significance of 5%. The values of cell viability ranged from 94.2% at 72h (SBU) to 109.6% at 48h (SB). The mean percentage of viability after exposure to the extracts of SB, SSAB and SBU were 103.2%, 100.63% and 97.43%, respectively. There was no statistically significant difference (p= 0.342) between the experimental and negative control groups. At all exposure times, all adhesives tested in this study presented no cytotoxicity to Vero cells in vitro

Pre-treatment oral microbiome analysis and salivary Stephan curve kinetics in white spot lesion development in orthodontic patients wearing fixed appliances. A pilot study

Abstract Background White spot lesions (WSLs) are a formidable challenge during orthodontic treatment, affecting patients regardless of oral hygiene. Multifactorial in nature, amongst potential contributors to their development are the microbiome and salivary pH. The aim of our pilot study is to determine if pre-treatment differences in salivary Stephan curve kinetics and salivary microbiome features correlate with WSL development in orthodontic patients with fixed appliances. We hypothesize that non-oral hygiene determined differences in saliva could be predictive of WSL formation in this patient population through analysis of salivary Stephan curve kinetics, and that these differences would further manifest as changes in the oral microbiome. Methods In this prospective cohort study, twenty patients with initial simplified oral hygiene index scores of “good” that were planning to undergo orthodontic treatment with self-ligating fixed appliances for at least 12 months were enrolled. At pre-treatment stage, saliva was collected for microbiome analysis, and at 15-minute intervals after a sucrose rinse over 45 min for Stephan curve kinetics. Results 50% of patients developed a mean 5.7 (SEM: 1.2) WSLs. There were no differences in saliva microbiome species richness, Shannon alpha diversity or beta diversity between the groups. Capnocytophaga sputigena exclusively and Prevotella melaninogenica predominantly were found in WSL patients, while Streptococcus australis was negatively correlated with WSL development. Streptococcus mitis and Streptococcus anginosus were primarily present in healthy patients. There was no evidence to support the primary hypothesis. Conclusions While there were no differences in salivary pH or restitution kinetics following a sucrose challenge and no global microbial differences in WSL developers, our data showed change in salivary pH at 5 min associated with an abundance of acid-producing bacteria in saliva. The results suggest salivary pH modulation as a management strategy to inhibit the abundance of caries initiators. Our study may have uncovered the earliest predecessors to WSL/caries development