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Oral and maxillofacial diseases affect millions of people worldwide and hence tissue engineering can be considered an interesting and clinically relevant approach to regenerate orofacial tissues after being affected by different diseases. Among several innovations for tissue regeneration, low-intensity pulsed ultrasound (LIPUS) has been used extensively in medicine as a therapeutic, operative, and diagnostic tool. LIPUS is accepted to promote bone fracture repair and regeneration. Furthermore, the effect of LIPUS on soft tissues regeneration has been paid much attention, and many studies have performed to evaluate the potential use of LIPUS to tissue engineering soft tissues. The present article provides an overview about the status of LIPUS stimulation as a tool to be used to enhance regeneration/tissue engineering. This review consists of five parts. Part 1 is a brief introduction of the acoustic description of LIPUS and mechanical action. In Part 2, biological problems in dentofacial tissue engineering are proposed. Part 3 explores biologic mechanisms of LIPUS to cells and tissues in living body. In Part 4, the effectiveness of LIPUS on cell metabolism and tissue regeneration in dentistry are summarized. Finally, Part 5 relates the possibility of clinical application of LIPUS in orthodontics. The present review brings out better understanding of the bioeffect of LIPUS therapy on orofacial tissues which is essential to the successful integration of management remedies for tissue regeneration/engineering. To develop an evidence-based approach to clinical management and treatment of orofacial degenerative diseases using LIPUS, we would like to be in full pursuit of LIPUS biotherapy. Still, there are many challenges for this relatively new strategy, but the up to date achievements using it promises to go far beyond the present possibilities.

The structure of the rainbands and eyewall of Typhoon 8514, which landed at the central region of Japan on 30 August 1985 was observed by two ground-based Doppler radars. The main purpose of the present study is to describe a general view of the structure of the typhoon using data of the dual-Doppler radar.Although the typhoon was a small and weak typhoon, it retained the characteristics of tropical cyclones: it was accompanied by spiral rainbands (an outer rainband and an inner rainband) and had a warm core in its upper part.The outer rainband was a spiral band located about 150 km from the center of the typhoon. This rainband consisted of continuous stratiform clouds and scattered convective clouds. A radar "bright band" was observed in this rainband. Wind perturbation induced by cooling-by-melting was observed just below the bright band. An updraft of 1.5 ms-1 was produced, mainly owing to the convergence of a southeasterly flow on the inner edge of the outer rainband. This updraft maintained the outer rainband.The inner rainband was a convective spiral band located *60 km from the typhoon center. The distribution of reflectivity and vertical velocity of this rainband indicated that an old echo cell existed in the inner part, while young echo cells existed in the outer part of this rainband. An inflow (the airflow toward the typhoon center) was observed in the lower layers of the inner rainband. This inflow reached the inner edge of the young cells, and produced an updraft there. When the depth of this inflow layer became thinner, the inner rainband decayed. This indicates that the inflow had an important role to play in maintaining the inner rainband.Because the flow into the eyewall of the typhoon in the lower layers was weak, the radius of maximum wind (RMW) was located at the outer side of the axis of reflectivity maxima. The eyewall decayed when it moved to the inner area (nearer the typhoon center) of the RMW, where downdraft was predominant.

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