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Can low-temperature plasma technology play a role in medicine? This is a question that many investigators today are trying hard to give a positive answer to. It did not quite start out this way. Almost two decades ago, few "curious" electrical engineers and physicists with the help of few "brave" biologists! microbiologists asked themselves more basic questions: What happens to biological cells if they were exposed to low-temperature plasma? Will they die? Will they survive? If they survive, will they come out the same or somehow "injured"? If injured, will they be able to repair the damage and recover? What kind of damage? Which plasma agent causes the damage? etc. As will be shown in this paper, some of these fundamental questions have been partially or fully answered, but until today, a complete picture has yet to emerge. This is good and not so good. It is good because if we already knew all the answers, we would not be looking forward to a more exciting research. It is not so good because after all these years, we are still quite a ways from an implementable medical application. In this review paper, the present state of knowledge regarding the effects of cold plasma on bacteria cells (prokaryotes) and on eukaryotic cells (such as mammalian cells) will be presented. As medical applications where low-temperature plasma is showing signs of success, blood coagulation and wound healing will be described. [ABSTRACT FROM AUTHOR]

The aim of this paper was to assess the effectiveness, safety, stability, and mechanism of tooth whitening using a direct current cold atmospheric pressure air plasma microjet (PMJ) with the assistance of whitening gels (blank or containing 3% H2O2). The results were compared with those obtained from teeth treated with blank gel only and with gel containing 35% H2O2 in a cold light bleaching system. Tooth whitening effectiveness right after various treatments as well as 18 months after treatment was evaluated via CIELAB colorimetry. Type K thermocouple, scanning electron microscope and energy dispersive spectroscopy were employed to study the temperature of pulp chamber, tooth surface morphology, and elemental composition of enamel surface, respectively. Teeth in the plasma groups were effectively whitened in 5 min, though no significant difference was observed between the two plasma groups. Pulp chamber temperature was shown to remain below 35 °C. Morphological and surface elemental analysis showed similar changes to tooth enamel in the plasma groups and in the cold light group. These observations suggested that PMJ with blank gel was more effective for tooth whitening with acceptable safety and good stability. Optical emission spectroscopy results revealed that reactive oxygen species, such as O, •OH, and NO, in plasma may play a dominant role in the process of plasma tooth whitening. [ABSTRACT FROM AUTHOR]

This paper is an essay narrating the recent history of the introduction of the biomedical applications of nonthermal plasmas to the plasma science research community. [ABSTRACT FROM AUTHOR]

Endoscopy is an important tool that can be used to identify and treat diseases and is essential to avoid cross infection when used on different people. Cold atmospheric-pressure plasmas (CAPs) offer the prospect of a future basic technology for decontaminating and sterilizing of endoscope. In this paper, we intend to design an endoscope sterilization device based on CAPs. The various lengths of gap between electrodes and electrodes themselves are considered, and the plasma distribution and its evolution are investigated. [ABSTRACT FROM PUBLISHER]

Plasma bullets have recently been used in novel applications in biology and medicine, which spurred interesting developments in the new interdisciplinary field of “Plasma Medicine.” In this paper, using high speed ICCD camera images we show that during their lifetime, plasma bullets undergo three distinctive phases: a launching phase during which the bullet velocity increases rapidly, a propagation phase during which the bullet velocity is temporarily maintained but later steadily decreases, and an ending phase during which the bullet collapses. [ABSTRACT FROM AUTHOR]

It is now well known that low-temperature plasmas can inactivate bacteria effectively. At low doses, these plasmas can also help in the proliferation of healthy fibroblasts and detach damaged cells without causing necrosis. The combination of these characteristics leads to the possibility of using plasmas in biomedical applications such as wound healing. Although only limited understanding is available as to the mechanisms whereby plasmas interact with cells (prokaryotic or eukaryotic), it is now well established that the effects of plasmas on biological cells depend on the cell type, the cell concentration, and the medium supporting them. In this paper, we present clear visual evidence of these dependencies in the case of bacteria. Through simple imaging, we show that the size and shape of the inactivation zone depend on the type of bacteria, their initial concentrations, and the medium supporting the cells. [ABSTRACT FROM AUTHOR]