ABSTRACT
Occlusal plane (OP) is one of the essential factors affecting craniofacial morphology and function. The OP not only assists in diagnosing malocclusion but also serves as an important reference for making treatment plans. Patients with different types of malocclusions have different forms of OP. Compared with patients with standard skeletal facial type, the occlusal plane of patients with skeletal class Ⅱ and high angle is steeper, while that of patients with skeletal class Ⅲ and low angle is more even. In orthodontic treatment, adjusting and controlling the OP can promote the normal growth and development of the mandible in most patients with malocclusion during the early stage of growth, while causing favorable rotation of the mandible in some adults with mild-to-moderate malocclusion. For moderate-to-severe malocclusion, the OP rotation by orthodontic-orthognathic treatment can achieve better long-term stability. This article reviews the evolution of the definition of OP and its implications for diagnosing and the guiding treatment of malocclusion.
Subject(s)
Adult , Humans , Dental Occlusion , Maxilla , Cephalometry , Malocclusion/therapy , MandibleABSTRACT
Research-oriented hospitals are the currently development direction of large hospitals, and their research ethics management has played an important role in China’s scientific and technological innovation and clinical research development through years of practice. However, at present, China’s overall scientific and technology ethics governance framework system is still incomplete, governance authority is insufficient, ethics committee members lack ethical professional technical training, and the awareness and understanding of science and technology ethics among medical staff still need to be improved, which indicates that the level of technology ethics governance in research-oriented hospitals needs to be improved. It is suggested to improve from the aspects of regulatory system, governance responsibilities, training of ethical practitioners, supervision and punishment measures, and ethical education of scientific and technological research talents, so as to better protect subjects and promote the construction of scientific and technological ethics in the research-oriented hospitals.
ABSTRACT
Extended clinical trials are medical treatment activity based on the humanitarianism to provide new medical products during the clinical trials for specific patients who have no other effective medical means to prolong life or alleviate pain. Extensive clinical trials have both medical and scientific attributes, which are significantly different from registered clinical trials and require special ethical attention. At present, the extended clinical trials in China are still in the initial stage, laws, regulations and supporting management methods are not perfect, and there is a lack of experience in ethical governance of such special clinical trials. This paper took the expanded clinical trial of medical devices as an example, referred to the current laws and regulations at home and abroad, analyzed their characteristics, and put forward some suggestions on the ethical governance of the whole process of the expanded clinical trials of medical devices in China,including special concerns in the application and acceptance, the first review approval strategy and the key points in continuing review.
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Objective To establish a blast injury experimental model using a shock tube at lateral lying position of C57BL/6 mice, investigate biomechanical responses of macrophages/microglia cells in the heart, lung and brain tissues to mechanical damage by shock wave within 24 hours. Methods Shock tube was employed to generate a shock wave to C57BL/6 mice. Firstly, the weight changes of mice were measured at different time points after the shock. Then the cardiac, pulmonary and whole brain tissue samples were dissected after anesthesia. Pathological sections were stained with HE staining to detect structural damage; the TUNEL staining method was used to mark and count the proportion of dead cells in each tissue. Microglial cells were labeled with fluorescent antibody, while responses and changes of macrophages/microglia after shock loading were analyzed. Results The shock tube exerted 179 kPa overpressure shock wave upon sideway of the mouse, and lethal rate of the mouse was 3.33%. Compared with normal control group, the mice in experimental group had a significant weight loss within 24 hours after loading shock. Pathological sections showed rupture of lung tissues after shock, accompanied by alveolar protein deposition, pulmonary bulla and other diseases. Fluorescence staining showed that lung tissue was recruited and activated in a large amount within 24 hours. The proportion of dead cells cleared rebounded to normal level within 24 hours. The heart was highly tolerant to shock, and macrophages appeared near the large blood vessels. The brain showed unilateral aggregation of microglia due to the impact posture, mainly due to prolonged inflammation and a higher proportion of dead cells at the junction of gray and white matter. Conclusions A blast shock model at lateral lying position of the mouse was established. Within 24 hours, macrophages/microglia were recruited quickly to the injury site after being impacted, which mediated strong immune stress, and might participate in the immune response to trigger a second long-term inflammatory injury. The results of the study provide experimental basis for the evaluation of primary impact injury, such as dose-effect relationship and tissue damage difference.
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Objective:To understand the current status and existing problems of medical students' cognition of new medical ethics view, and to provide reference for the innovation of medical ethics education mode. Methods:A self-designed questionnaire was used to investigate the medical students in a university in Changsha. A total of 450 questionnaires were distributed and 440 questionnaires were collected. Results:Medical students generally had a better understanding of the new medical ethics view and could establish a"patient centered" service concept. But the medical ethics cognition of some medical students was not consistent with the medical ethics behavior, and the medical value orientation was not clear. Conclusion:In order to improve the medical ethics cognition level of medical students, it needs to establish a new medical ethics education mode with the integration of school, society and family, make medical ethics education integrate with clinical practice effectively, strengthen medical students' legal education meanwhile, and effectively carry out the new medical ethics view for medical students.
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Objective To investigate ultrahistopathological features of symmetrical acrokeratoderma.Methods Biopsy specimens were obtained from skin lesions and perilesional normalappearing skin of 6 patients with symmetrical acrokeratoderma,as well as from normal skin of 3 healthy volunteers.Then,these skin specimens were subjected to transmission electron microscopy (TEM).Results TEM showed obviously thickened stratum corneum,irregular morphology of keratinocytes and discontinuous cornified envelope.Aggregation and abnormal arrangement of keratin filaments occurred in all epidermal layers.Many vacuoles of different sizes were observed in the transitional zone between the stratum corneum and stratum granulosum.Hypogranulosis,abnormal shape and different sizes of keratohyalin granules,and reduction of membrane-coating granules were found in the stratum granulosum.Increased melanocytes with a large number of stage Ⅳ melanosomes in the cytoplasm were observed in the basal layers.Moreover,there was infiltration of a few lymphocytes in the superficial dermis.Perilesional normal-appearing skin tissues showed similar but milder ultrastructural changes.Conclusion Abnormal metabolism of keratins,epidermal differentiation complex proteins and lipids may exist in skin lesions of symmetrical acrokeratoderma,which may contribute to epidermal thickening and impairment of skin barrier function.
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By referring to the domestic and foreign relevant regulatory guidelines, this paper analyzed and sum-marized the ethical point in the design phase in the perspective of relevant regulations of clinical waste sample man-agement and biological sample management. It also analyzed the focus problems including the difference in sample library and clinical laboratory remaining sample as well as the ownership of the sample, to provide theoretical basis for ethics committee to review this kind of protocols.