Difference of Chemical Bonds Between UDMA Bonding Agents with Ethanol Solvent and Acetone Solvent on Dentin Collagen

ABSTRACT Objective: To investigate the difference of chemical bonds between urethane dimethacrylate (UDMA) bonding agents with ethanol solvent and acetone solvent on dentin collagen. Material and Methods: This experimental comparison study used three groups: G1 (Control): UDMA and collagen; G2: UDMA, collagen and ethanol; and G3: UDMA, collagen and acetone. The groups were then pelleted and analysed with FTIR, then the peak value of carbonyl absorption band from each study group was calculated. The result of FTIR analysis and the peak of carbonyl absorption band (P) was calculated using the formula: P = (BC / AB) X 100; AB. BC is measured in centimeters. The study of chemical bond differences between ethanol-solvent UDMA agents compared with acetone-solvent on dentin collagen resulted in a graph of peak of carbonyl absorption bands of UDMA and dentin collagen groups. To determine the chemical bonds of UDMA from the top of the carbonyl ester absorption bands with wavenumber absorption in range 1700-1750 cm-1, the decreasing peak of the carbonyl absorption bands is assumed as more chemical bonds that formed. Data were analysed using Anova one way and Tukey HSD test. Results: There were significant differences between the three study groups (p<0.05). Conclusion: UDMA bonding agents' chemical bonds with acetone solvent are much higher than the chemical bonds between UDMA bonding agents with ethanol solvent on dentin collagen.

Risk assessment of aflatoxin B1 exposure from maize and peanut consumption in Indonesia using the margin of exposure and liver cancer risk estimation approaches.

Aflatoxin B1 (AfB1) is a secondary fungal metabolite product widely found in many foodstuffs and considered a public health concern worldwide due to its genotoxicity and carcinogenicity. Tropical climate and inappropriate food safety practices in Indonesia are the favorable conditions for AfB1 contamination of foodstuffs. Despite these challenges, there has been a limited number of risk assessment of AfB1 conducted in Indonesia. Therefore, this paper aimed to gather all available occurrence data of AfB1 in maize and peanut originating from Indonesia and used the occurrence data to evaluate the risk of exposure to AfB1 using the Margin of Exposure (MOE) and the quantitative liver cancer risk approaches established by EFSA and FAO/WHO respectively. Risk assessment using both the MOE and quantitative liver cancer risk approaches revealed that AfB1 exposure from maize and peanut consumption in Indonesia is of concern. The MOE values derived from consumption of maize and peanut originating from Indonesia were generally below 10,000, and for several occurrence data were even below 1000. The estimated number of liver cancer cases associated with AfB1 exposure generally was above the 0.1 cancer cases/100,000 individuals/75 years. Altogether the evaluation reveals the urgency for risk management of AfB1 in Indonesia.