Development of a customisable 3D-printed intra-oral stent for head-and-neck radiotherapy.

Intra-oral stents (including mouth-pieces and bite blocks) can be used to displace adjacent non-involved oral tissue and reduce radiation side effects from radiotherapy treatments for head-and-neck cancer. In this study, a modular and customisable 3D printed intra-oral stent was designed, fabricated and evaluated, to utilise the advantages of the 3D printing process without the interruption of clinical workflow associated with printing time. The stent design used a central mouth-opening and tongue-depressing main piece, with optional cheek displacement pieces in three different sizes, plus an anchor point for moulding silicone to fit individual patients' teeth. A magnetic resonance imaging (MRI) study of one healthy participant demonstrated the tissue displacement effects of the stent, while providing a best-case indication of its comfort.

Accuracy, comprehensibility, and use of material safety data sheets: a review.

OBJECTIVES: Material safety data sheets (MSDSs) are used in workplaces to communicate to workers the hazards of chemical products. This article describes a review of the peer-reviewed scientific literature regarding the accuracy, comprehensibility and use of MSDSs in the workplace. METHODS: Articles were retrieved via a systematic search of indexes and databases, followed by hand searching and citation index searching. Two reviewers independently read and coded the articles using an iterative matrix. RESULTS: Of the 280 unique articles retrieved, 24 fit the review criteria. Eligible articles included a range of methodologies: laboratory analyses, site audits, surveys and qualitative inquiry. Articles were grouped into three main topic categories: accuracy and completeness, awareness and use, and comprehensibility. Accuracy and completeness were found to be relatively poor, with the majority of studies presenting evidence that the MSDSs under review did not contain information on all the chemicals present, including those known to be serious sensitizers or carcinogens. Poor presentation and complex language were consistently associated with low comprehensibility among workers. Awareness and use of MSDSs was suboptimal in workplaces where these factors were studied. CONCLUSIONS: Despite the fact that these studies varied in methodology and spanned a period of more than 15 years, a number of common themes emerged regarding inaccuracies, incompleteness, incomprehensibility and overall low use of MSDSs. The results of the literature review suggest that there are serious problems with the use of MSDSs as hazard communication tools. The article concludes with recommendations for governments, regulatory bodies, and occupational health and safety personnel to seriously reassess the ways in which MSDSs are written, monitored, regulated, and used.