Multimodal approach from various medical fields is required to accurately diagnose and appropriately treat obstructive sleep apnea syndrome, and to fully understand its pathogenesis. Dental medicine has contributed to clarifying importance of craniofacial abnormalities for development of obstructive sleep apnea. It also plays a major role in treatment of obstructive sleep apnea with oral appliances, maxillomandible surgeries and orthodontic interventions. It is expected that orthodontic intervention during childhood even in asymptomatic child possibly prevents development of obstructive sleep apnea during adulthood while extensive involvement of the dentists is needed to test the hypothesis.

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Globalization in dental education is an important issue in Japan. However, implementing strategies for globalization related to aspects such as infrastructure, educational goals and content, educational methodologies, and standards is not easy. The dental training programmes at the Faculty of Dentistry at The University of Hong Kong can offer some insight into the process. While The University of Hong Kong is world-renowned and has embraced globalization, it is located in Asia, where English is not the native language. The latter reflects the same situation as in Japan, but the Hong Kong and Japanese dental schools differ considerably in the medium of education, teaching styles, undergraduate curriculum, postgraduate education system, character of the students, and duties of the academic staff. Dental education at The University of Hong Kong may thus provide a role model for the planning and integration of globalization within the tertiary dental education system in Japan.

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Over the last decade, a lot of literature has unraveled functions of innate immune cells, such as monocyte, macrophage and dendritic cell. The inflammatory responses to infectious microorganisms are generated by the innate immunity and induce acquired immune activation subsequently. As the innate and adaptive immune systems are intertwined, it is impossible to protect our body without the connection with both immune systems. Macrophage activation is tightly controlled by regulatory mechanism which are generally requires a very complicated regulation by both transcriptional molecules and receptors on the surface. In addition, the innate immune system also has different features that function as scavenging foreign substances in the host body. The detailed mechanisms by which molecular mechanism induce alternative activation in macrophage are not yet known. The future direction of immunological research is discussed in the last part.

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The osseointegration capacity of implant surfaces deteriorates over time. However, the treatment of titanium surfaces with ultraviolet (UV) light restores the original properties of the surface and causes considerable acceleration in the process of osseointegration. This study reviews two recent findings: the aging-like time-dependent biological degradation of titanium surfaces and the discovery of UV photofunctionalization as a solution to this phenomenon. This technology and the associated knowledge herald a new age of implant treatment and provide a novel concept of osseointegration in the science and therapeutics of implant dentistry. In addition, we expect to revolutionize clinical implant therapy through these new concepts.

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The A7 cell group in the dorsolateral pons provides noradrenergic innervation of the spinal cord. Activation of this descending pathway (the A7 descending system) produces bi-directional effects on nociceptive processing in the dorsal horn, which are facilitation mediated by α₁-adrenoceptor and inhibition via α₂-adrenoceptor. Peripheral nerve injury sometimes results in neuropathic pain. Hypersensitivity of dorsal horn neurons under neuropathic conditions is linked to activity in descending pathways from the brain. The aim of this study was to examine the involvement of the A7 descending system under neuropathic conditions. Experiments were performed on male Sprague-Dawley rats (n=35). Bilateral lesions of the A7 area were performed by microinjection of kainic acid. The tibial and common peroneal the nerves were sectioned produce neuropathic conditions (spared nerve injury, SNI). For estimating mechanical allodynia, mechanical hypoalgesia and cold allodynia, paw withdrawal threshold (PWT), paw withdrawal latency (PWL) and paw withdrawal frequency (PWF) were measured. PWTs significantly decreased following A7 lesions. After SNI, PWTs significantly decreased in A7-lesioned and sham-lesioned rats. However, no significant difference was observed between the decreased rates of PWTs in A7-lesioned and sham-lesioned rats. PWLs significantly increased in sham-lesioned rats compared with A7-lesioned group. PWFs significantly increased in the A7-lesioned and sham-lesioned rats. Intrathecal injection of prazosin, an α1-adrenoceptor antagonist, failed to change the PWT, PWL and PWF in non-A7-lesioned neuropathic rats. These results suggest that (1) the A7 descending inhibitory system has tonic activity under normal conditions, and (2) this system functions in a complex manner during the neuropathic pain state.

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Molar extraction, tongue habit and finger sucking etc. are frequently the cause of open-bite. Generally, open-bite caused temporarily in the second molar eruption period would be improved by the force of biting. The patient, a 15-year-4-month-old female, came in with the chief complaint being the inability to chew food. At the age of 13, she had presented with TMJ pain and TMJ sounds, and a splint was used to improve those TMJ symptoms. Though the TMJ symptoms were alleviated, total open-bite appeared everywhere except the second molar, and so she consulted an orthodontic clinic. Orthodontic treatment involved the extraction of the upper second molar on both sides, and the use of multi-bracket devices to improve open-bite in a short period.

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The Invisalign system is widely used to treat mild to moderate tooth crowding. Recently, Invisalign appliances have been used in orthodontic patients with increasingly complex malocclusions. When using an Invisalign appliance to correct severe tooth crowding, root positions must be carefully controlled during extraction space closure. We report our treatment of a 34-year-old man who presented with a Class I relationship, a midline deviation, severe overjet, and severe tooth crowding in the maxillary and mandibular anterior regions. The treatment plan involved extraction of the maxillary and mandibular first premolars on both sides. We treated this patient with severe anterior tooth crowding using an Invisalign appliance combined with a fixed appliance with power arms and elastics. Treatment by Invisalign as an application of computational calculated result, especially in extraction cases, doctors should have professional skill and experience as an orthodontist.

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[in Japanese]

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[in Japanese]

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