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Abstract
Nowadays, with the current trend towards “minimal invasiveness”, adhesive and esthetic dentistry concepts with different tooth colored restoratives, different instrumentation techniques can be applied to remove caries and to make the tooth surface receptive for bonding (1-5).
Drilling with a diamond or tungsten carbide bur is the most common way of cavity preparation, but more researches has been carried out on alternative means of preparing tooth tissue. Bur preparation of cavities often leads to more extensive cavities as compared with the initial caries lesions. Moreover, approximal beveling of cavities is difficult, and adjacent teeth are often touched and damaged by the bur, also formation of smear layer (6-8) .
These drawbacks of rotary instruments for cavity preparation, along with the current trend towards “minimal invasiveness” (1-3) have led to the introduction of new tools or the revival of already existing techniques, such as sono-abrasion, air abrasion, and laser ablation (6,9,10).
Since the discovery of ruby laser (Maiman 1960), there were an advanced use of laser in dentistry. Several types of laser e.g. CO2 and Nd:YAG lasers have shown their insufficiency due to required relatively high energy.