Leo Zach

Bio: Leo Zach is an academic researcher from New York University. The author has contributed to research in topics: Pulp (tooth) & Thermogenesis. The author has an hindex of 5, co-authored 6 publications receiving 1175 citations.

Ultrasonic cavijty preparation: histopathologic survey of effects on mature and developing dental tissues

Abstract: The histopathologic effects of ultrasonic cavity preparation in permanent teeth (human) and in permanent, deciduous and underlying permanent teeth of primates were studied. The response in the pulp was mild and generally indicated a reversible reaction, in all aspects comparable to the response caused by rotary technics. No evidence was found of any pathologic condition in the supporting structures nor was aberration ar dysplasia seen in growing structures or tissues. Pulp response to the cutting of dentin cannot be distinguished according to the instrument which does the cutting.

Ultrasonic cavity preparation: Effect on the immature dentition

Abstract: T HE GROWTH OF THE REALIZATION that clinical dental treatment is founded on a basic scientific rationale has received powerful impetus by the introduction of the ultrasonic dental tool. Histopathologic evaluation of the new device, an analysis of potential tissue effects resulting from clinical use, was soon recognized by the profession as a necessity for thorough appraisal. Early report& 2, 3 attested to the mechanical effectiveness of the ultrasonic tool in removing tooth substance; manipulative advantages to the operator, technical advantages in the smoothness and precision of the preparations, and human advantages in terms of lessened stress to the patient were outlined and evaluated. The new modality of energy application to the tooth heightened the need for a biologic assay of tissue response in comparison with tissue effects produced by rotary instrument cavity preparation. Preliminary papers4-* were devoted to pulp studies of adult, erupted teeth in both humans and animals. Reactions were generally mild and judged reversible. A study9 of heat flow within the pulp and at the apex of the tooth, induced by cavity preparation, indicated no thermogenesis beyond 14” F. with any device, including ultrasonics, when water coolant was used. Safe limits prevailed. One report, however, by Hansen and Nielseni focused attention in a new direction ; on the possible effect of ultrasonic preparation on extremely labile, growing dental structures. Their findings disclosed a dysplastic response, inducing distortion of amelogenesis and disruption of dentinogenesis in the continuously erupting guinea pig incisor subjected to ultrasonic cavity preparation. Though no direct homologue exists in higher animal orders, this report on a tooth of continuous growth bore implications of potential effects on the immature dentitions of children. This article is an attempt to evaluate the ultrasonic device as used in the preparation of cavities in deciduous and immature permanent teeth. It is aimed as a histologic bio-assay of ultrasonic effect on the deciduous tooth being shed, the underlying permanent tooth and its developing membranes, and the young permanent tooth with incomplete root, together with supporting and surrounding structures.

Lasers in dentistry.

Abstract: Since the development of the ruby laser by Maiman in 1960, there has been great interest among dental practitioners, scientists, and patients to use this tool to make dental treatment more pleasant. Oral soft tissue uses are becoming more common in dental offices. The possible multiple uses of lasers in dentistry, beyond soft tissue surgery and dental composite curing, unfortunately, have not yet been realized clinically. These include replacement of the dental drill with a laser, laser dental decay prevention, and laser decay detection. The essential question is whether a laser can provide equal or improved treatment over conventional care. Safe use of lasers also must be the underlying goal of proposed or future laser therapy. With the availability and future development of different laser wavelengths and methods of pulsing, much interest is developing in this growing field. This article reviews the role of lasers in dentistry since the early 1960s, summarizes some research reports from the last few years, and proposes what the authors feel the future may hold for lasers in dentistry.

History, safety, and effectiveness of current bleaching techniques and applications of the nightguard vital bleaching technique.

Abstract: This article reviews the literature on the use of hydrogen peroxide in three professionally administered bleaching techniques from historical, technique, and safety viewpoints. Safety over time, absolute safety, and relative safety of nonvital bleaching, in-office vital bleaching, nightguard vital bleaching, and over-the-counter bleaching kits are compared. The advantages and disadvantages of different bleaching options, as well as indications for individual or combined use of the techniques, are discussed. In addition, specific indications for the use of the nightguard vital bleaching technique are presented.