Much effort is invested in the development of tissue-saving methods in dentistry. Cleaning and sterilization of infected tissue in a dental cavity or in a root channel can be accomplished using mechanical or laser techniques. However, with both approaches, heating and destruction of healthy tissue can occur. Recently, a nonthermal atmospheric plasma (plasma needle) has been developed. In this work, the interactions of this plasma with dental tissue is studied, and its capability of bacterial inactivation is tested. A plasma needle is an efficient source of various radicals, which are capable of bacterial decontamination; however, it operates at room temperature and thus, does not cause bulk destruction of the tissue. Plasma treatment is potentially a novel tissue-saving technique, allowing irregular structures and narrow channels within the diseased tooth to be cleaned.