Effect of denture adhesives on masticatory performance: Multicenter randomized controlled trial.

PURPOSE: The purpose of this study is to investigate the effects of denture adhesives on masticatory performance via a 10-center, parallel, randomized, controlled trial of complete denture wearers in Japan. METHODS: The trial was conducted between September 2013 and October 2016. The inclusion criteria were complete edentulism, willingness to undergo new complete denture treatment, and willingness to return for recall treatment. The exclusion criteria were age 90 years or older, presence of severe systemic illness, inability to understand the questionnaires, wearing metal base complete dentures, denture adhesive user, wearing prosthetics for maxillofacial defects, wearing complete dentures with tissue conditioners, and severe xerostomia. Randomization of the powder-type denture adhesive (powder), cream-type denture adhesive (cream), and control (saline) groups was performed using a sealed envelope system. Masticatory performance was measured using color-changeable chewing gum. Intervention blinding was not feasible. RESULTS: Sixty-seven control, 69 powder, and 64 cream participants are analyzed using the intention-to-treat principle. The participants in all groups show significantly improved masticatory performance at post-intervention (paired t-test with Bonferroni correction P < 0.0001). However, no significant difference in masticatory performance is detected among the three groups (one-way analysis of variance). A significant negative correlation between pre- and post-changes in masticatory performance and intraoral condition scores is observed (Pearson's correlation coefficient, P < 0.0001). CONCLUSIONS: Although denture adhesives improved the masticatory performance of complete denture wearers, their clinical effects are comparable to those of saline solution. The use of denture adhesives is more effective in complete denture wearers with unsatisfactory intraoral conditions.

The potential effect of ethyl alcohol elution from liner type denture adhesives on breath alcohol concentration and determination of drunk driving.

Background/purpose: The application of liner type denture adhesives containing ethyl alcohol (EtOH) may result in the person being considered a drunk driver, which is a social problem. This study measured the amount of EtOH loss from the materials and its effect on breath alcohol concentration (BrAC). Materials and methods: The amount of EtOH loss of three liner type denture adhesives was measured using a gas chromatograph-mass spectrometer. Five specimens were measured for each material. The BrAC of ten participants who wore the palatal plate lined with the material having the highest amount of EtOH elution was also determined using an alcohol detector every 5 min for 60 min. The threshold for drunk driving was a BrAC of 0.15 mg/L or more. Results: Significant differences were found in the amount of EtOH elution among the three materials. For all materials, the elution amount from the start of immersion to 30 min was significantly larger than that of the following 30 min (P < 0.05). BrAC values of the participants reached their maxima 5 min after insertion of the materials, and 80% of participants surpassed the threshold for drunk driving. However, no participants reached the threshold for drunk driving after 50 min. Conclusion: The results suggest that a determination of drunk drinking will not be made when 1 h or more has passed after insertion of a denture lined with a liner type denture adhesive into the mouth, though a determination of drunk driving may exist due to EtOH from the materials.

Predictive markers based on transcriptome modules for vinorelbine-based adjuvant chemotherapy for lung adenocarcinoma patients.

OBJECTIVES: Microtubule inhibitors (MTIs) are widely used as anti-cancer drugs for various types of tumors. Vinorelbine, an MTI, is utilized in postoperative adjuvant chemotherapy, especially for lung adenocarcinoma. However, no molecular markers are able to identify patients for whom MTIs would be effective. In this study, we attempted to identify practical markers to predict the efficacy of MTI-based adjuvant chemotherapy. MATERIALS AND METHODS: We explored a novel combination of molecular marker candidates, based on gene expression network analysis constructed using an omics panel of 26 lung adenocarcinoma cell lines. We then applied the obtained classification method to predict the efficacy of MTI treatment in patients who received adjuvant chemotherapy. RNA sequencing (RNA-seq) analysis was conducted using surgical specimens from 24 Japanese lung adenocarcinoma patients treated postoperatively with vinorelbine. RESULTS: We identified four modules within the network with module activities that were significantly associated with sensitivity to MTIs. Two modules were associated with high sensitivity to MTIs: genes with low differentiation or transdifferentiation of lung adenocarcinomas. On the other hand, MTI-low sensitivity modules were enriched in common epithelial genes and markers of well-differentiated lung adenocarcinomas. We also classified lung adenocarcinoma cases using the module activities associated with MTI efficacy and stratify the cases with MTI resistance. CONCLUSION: We demonstrate that the constructed classification method is useful for identifying patients with MTI resistance which results in a high risk of cancer relapse.

Influence of monomer type, plasticizer content, and powder/liquid ratio on setting characteristics of acrylic permanent soft denture liners based on poly(ethyl methacrylate/butyl methacrylate) and acetyl tributyl citrate.

We evaluated the influence of monomer type, plasticizer content, and powder/liquid (P/L) ratio on the setting characteristics of light-cured acrylic permanent soft denture liners based on poly(ethyl methacrylate/butyl methacrylate). Two monomers, iso-butyl methacrylate (i-BMA) and 2-ethylhexyl methacrylate (2-EHMA), that contained various concentrations of the plasticizer acetyl tributyl citrate (ATBC) and trace amounts of the photo initiator and reducing agent were used. The P/L ratio was 1.0 or 1.2. The gelation time was measured using a controlled stress rheometer. Materials with i-BMA had shorter gelation times than those for materials with 2-EHMA. The gelation time increased exponentially with increasing plasticizer content. A higher P/L ratio led to a shorter gelation time. The effects of monomer type and plasticizer content were larger than that for the P/L ratio. These results show that 2-EHMA is a suitable monomer for soft denture liners and that the setting characteristics can be controlled via ATBC content.

Influence of composition and powder/water ratio on adhesion strength and initial viscosity of powder-type denture adhesives based on CMC-Na and PVM-MA.

We evaluated the influence of the composition and powder/water (P/W) ratio of powder-type denture adhesives (DA) based on sodium carboxymethyl cellulose (CMC-Na) and poly(methyl vinyl ether-maleic anhydride) (PVM-MA) on the strength of adhesion to acrylic resin and initial viscosity. Twenty types of DA were prepared by mixing CMC-Na and PVM-MA at various weight ratios with distilled water in P/W ratios ranging from 0.125 to 0.500. Adhesion strength and viscosity were measured using a universal testing machine and a controlled-stress rheometer, respectively. A higher percentage of CMC-Na and higher P/W ratios resulted in higher adhesion strength and viscosity. The effect of the CMC-Na/PVM-MA weight ratio on adhesion strength and viscosity was larger than that of the P/W ratio. DA with higher viscosity had higher adhesion strength. These results suggest that the adhesion strength and initial viscosity of powder-type DA can be controlled via the P/W ratio and the CMC-Na/PVM-MA weight ratio.