Deformation behavior of normal human enamel: A study by nanoindentation.

Tooth enamel has an important mechanical function for human dental health, yet characterizing its mechanical properties is not trivial due to its complex nanoporous structures. We examined the distribution of hardness and modulus across the lingual-buccal enamel cross-section by nanoindentation. At the occlusal surface, the hardness and modulus of enamel were found to be 5.00 ± 0.22 GPa and 97.12 ± 2.95 GPa, respectively. At the area close to the enamel-dentine-junction (EDJ), the hardness and modulus were 3.72 ± 0.35 GPa and 76.83 ± 5.71 GPa, respectively. At the middle region in between the EDJ and the outer enamel layer, the hardness and modulus were found to be 4.23 ± 0.18 GPa and 87.62 ± 2.50 GPa, respectively. The surface and area underneath the nanoindent were analyzed using the following microscopy tools: Scanning Electron Microscopy, Focused Ion Beam imaging, and Transmission Electron Microscopy. The deformation mechanisms of enamel were found to be location dependent and influenced by changes in the chemical composition within enamel. The EDJ forms the interface between enamel and dentin. The deformation behavior differed at the EDJ, due to the increased organic phase at the interface. Within the intermediate enamel region, intra-rod cracks were formed at the center of enamel rods and propagated into the neighboring inter-rod region at deviated directions along the orientation of the local crystallites. At the outer enamel layer, crack propagation was constrained by the rigid structure surrounding the indented site. Most of the cracks were formed close to the surface. A significant amount of material was also pushed upwards and delaminated from the enamel surface of the indentation area.

Towards the Sustainable Development Goals: implications for health systems in the Western Pacific

Adopted by the General Assembly of the United Nations in 2015, the Sustainable Development Goals (SDGs) build on the lessons learned from the Millennium Development Goals that had guided development efforts for the preceding 15 years. The World Health Organization (WHO) Western Pacific Region made remarkable progress towards the Millennium Development Goals, but also experienced some challenges and shortcomings. This paper argues that the SDGs incorporate these complexities and aim to capture the many ways in which equitable and robust development is shaped by factors which are linked to each other. The SDGs place greater emphasis on a broader range of determinants of health, including poverty reduction, education, and reducing inequality, thereby reflecting that health influences and is influenced by progress on all goals and targets. Drawing on recent World Health Organization frameworks, the paper suggests options for advancing the SDGs in the Western Pacific. It argues that universal health coverage is core to achieving the SDGs and enacting the principle of leaving no-one behind, and outlines new ways of working within and outside of the health sector as well as appropriate capabilities of the health sector to drive the agenda. The SDGs place renewed demands on Member States and their partners. The strengths of the SDG framework lie in the emphasis on collaboration and joint action to solve shared problems, on collective accountability and the public interest, on tackling the determinants of health, and notably on the primacy of reaching those left furthest behind.

Effects of Diabetic Case Management on Knowledge, Self-Management Abilities, Health Behaviors, and Health Service Utilization for Diabetes in Korea

PURPOSE: This study aimed to evaluate the effects of a case management program for diabetics, using a pre-post comparison design. MATERIALS AND METHODS: The study population comprised 6007 diabetics who received case management intervention in 2006 and were sampled nationwide in Korea. Before and after the intervention, the study population answered questions regarding their knowledge of diabetes, self-management ability, and health behaviors. Body mass index (BMI) was also calculated. Healthcare service utilization for diabetes was extracted from health insurance claim data from 2005 to 2007. RESULTS: The case management program significantly improved the study population's knowledge of diabetes and ability to self-manage nutrition, blood glucose monitoring, foot and oral care, and medications. This program also significantly changed the study population's health behaviors regarding smoking, alcohol drinking, and exercise, and BMI was positively affected. In the over-serviced subgroup, there was a significant decrease in the number of consultations (mean=7.0; SD=19.5) after intervention. Conversely, in the under-serviced subgroup, there was a significant increase in the number of consultations (mean=3.2; SD=7.9) and the days of prescribed medication (mean=66.4; SD=120.3) after intervention. CONCLUSION: This study showed that the case management program led the study population to improve their knowledge, self-management ability, health behaviors, and utilization of health care. It is necessary in future studies to evaluate the appropriateness of healthcare usage and clinical outcome by using a control group to determine the direct effectiveness of this case management program.