Personalized Preclinical Training in Dental Ergonomics and Endodontics in Undergraduate Dentistry Students (Pilot Study).

The curriculum at the Department of Pathophysiology in the Periodontal Sciences program at Okayama University includes normative preclinical training (NPT) using phantoms. NPT is given to the whole class of 5 th year students divided in groups of 8 students/instructor. In 2019, an innovative personalized preclinical training (PPT) pilot study was implemented for this group of students whereby two students, each with their own dental unit, were coached by one instructor. The main topics covered were dental ergonomics and endodontics. We aimed to evaluate the effectiveness of PPT in dental ergonomics and endodontics toward increasing the knowledge and future clinical skills of students who had already undergone NPT. A test on endodontics was taken before and after PPT. A questionnaire was completed to assess their perception of improvement regarding the above-mentioned topics. Test scores and questionnaire results both showed that the students' level of knowledge and awareness of future clinical skills was significantly higher after PPT. This pilot study demonstrated that PPT increased the students' knowledge and future clinical skills. As preclinical training forms the foundation for clinical practice, investment in future research regarding this personalized approach is likely to enhance students' understanding and clinical performance.

Arsenic Retention in Foliage and Soil after Monosodium Methyl Arsenate (MSMA) Application to Turfgrass.

Monosodium methyl arsenate (MSMA) is a commonly used herbicide for weed control in turfgrass systems. There is concern that arsenic from applied MSMA could leach to groundwater or run off into surface water, thereby threatening human and ecosystem health. The USEPA has proposed a phase-out of the herbicide but is seeking additional research about the toxicity and environmental impacts of MSMA before establishing a final ruling. Little research has systematically investigated MSMA in field-based settings; instead, risks have been inferred from isolated field measurements or model-system studies. Accordingly, the overall goal of this study was to quantify the fate of arsenic after MSMA application to a managed turfgrass system. After MSMA application to turfgrass-covered and bareground lysimeters, the majority of arsenic was retained in turfgrass foliage and soils throughout year-long experiments, with 50 to 101% of the applied arsenic recovered in turfgrass systems and 55 to 66% recovered in bareground systems. Dissolved arsenic concentrations from 76.2-cm-depth pore water in the MSMA-treated soils were consistently <2 µg L, indistinguishable from background concentrations. As measured by adsorption isotherm experiments, MSMA retention by the sandy soil from our field site was markedly less than retention by a washed sand and a clay loam. Collectively, these results suggest that under aerobic conditions, minimal arsenic leaching to groundwater would occur after a typical application of MSMA to turfgrass. However, repeated MSMA application may pose environmental risks. Additional work is needed to examine arsenic cycling near the soil surface and to define arsenic speciation changes under different soil conditions.