From the Editors: Emerging Applications of Lasers in Dentistry

Abstract

Summary The use of lasers in dentistry is already a clinical reality. New and exciting developments are presently being studied with the expectation of clinical implementation in the next few years. Since the invention of the first laser in 1960 the use of lasers for dental applications has been of great interest, not only in science and medicine, but also amongst the general public. Some expectations have yet to be accomplished, while others are already met. The early dream of removing caries (dental decay) without contact and appreciable pain, for example, has become reality, and is carried out in daily dental practice in several countries. Also other laser applications are already in clinical use. These include caries detection, etching of enamel and dentine for adhesive restorations, polymerisation of composites, bacteria reduction in root canals and in the periodontal pocket, calculus removal, laser assisted tooth whitening, and several types of soft tissue surgical procedures. The contributions compiled in this issue cover some of the most interesting questions regarding actual and future dental laser applications. For the logical development of potential indications, a basic understanding of interactions between laser irradiation and dental hard tissues is indispensable. The first paper in this issue (Featherstone and Fried) provides such information. As a special focal point the topic of laser assisted caries prevention is highlighted. Caries prevention is also one of the dreams of the pioneers of laser dentistry. Initial attempts to vitrify enamel by high temperatures resulting from treatment with lasers led to the desired reduction in enamel solubility but were not applicable clinically due to excess heat which caused major tissue damage. Now with a true scientific understanding of laser/tissue interactions research is quickly approaching achievement of this aim. In order to prevent progression of dental caries it must be detected at an early stage so that sound tissue can be retained intact while intervention therapy is in progress. For early detection of caries (laser) light induced fluorescence has been demonstrated to be a powerful method. One such device is currently in use clinically, but much work is still experimental. The following two papers describe two complementing approaches: (a) excitation by green light for quantitative analysis of initial caries (Tranaeus et al.), and (b) excitation by red light for detecting and monitoring of “hidden” caries covered by macroscopically intact enamel (Hibst et al.). For caries removal and cavity preparation pulsed Er:YAG lasers have been shown to be a safe and nearly painless alternative to mechanical drills. They have been approved by the American Food and Drug Administration (FDA) and are used in clinical practice. Whereas prior investigations were performed on adult subjects, the paper by Den Besten et al. reports for the first time a clinical study using this technology on children. Er:YAG lasers can also be used in periodontology for calculus removal. The effect of this and other lasers is reviewed by Rechmann and Hennig. Special emphasis is given to selective calculus removal as demonstrated for the frequency doubled Alexandrite laser. Last, but not least, certain lasers can be used for treatments of the root canal. One important application is the killing of bacteria, but there are also a variety of other applications. These are summarised and illustrated by De Paula Eduardo and Gouw-Soares. These comprehensive overviews, which include the latest results, are not only addressed to respective scientists and clinicians, but also should provide all other interested readers with state-of-the-art information on emerging applications of lasers in dentistry.