title: Noncontact Er:YAG laser ablation: clinical evaluation.
abstract: OBJECTIVE
  The aim of this study is to evaluate the quality of laser ablation in comparison with the classical drilling preparation.
  
  
  METHODS
  For the experiment, the Er:YAG laser drilling machine was used. The system had a laser head, water cooler, and power supply with automatic control. Spot size of 300-350 microns was used for the preparation. Repetition rate of 1-4 Hz, and pulse energies of 100-400 mJ with water spray were chosen. Cavity shape in comparison with classical drill, time of preparation, and influence of cavity shape on filling materials retention in accordance with the U.S. Public Health Service System were used. The evaluation criteria for noncontact Er:YAG ablation were done.
  
  
  RESULTS
  The cavity shape is irregular, but spot surface has larger area and microretentive appearance. Caries of enamel and dentin were treated with a noncontact preparation. It was possible to remove the old insufficient fillings, except for amalgam or metal alloys. The average number of pulses was 111.22 (SE 67.57). Vibrations of microexplosions during preparation were felt by patients on 14 cavities; however, nobody felt unpleasant pain. The qualities of filling materials in laser cavities were very stable; however, cavo surface margin discoloration of 82-86% of Alfa rating could be a problem. Changes of the color and anatomic form of the tooth were observed in 4-8%.
  
  
  CONCLUSIONS
  In comparison with the classical treatment, it could be said that the retention and quality of filling materials is the same or very similar.
authors.affiliation: Institute of Dental Research, Prague, Czech Republic. dostalova@vus.cz
authors.forename: T
authors.initials: T
authors.lastname: Dostálová
authors.forename: H
authors.initials: H
authors.lastname: Jelínková
authors.forename: H
authors.initials: H
authors.lastname: Kucerová
authors.forename: O
authors.initials: O
authors.lastname: Krejsa
authors.forename: K
authors.initials: K
authors.lastname: Hamal
authors.forename: J
authors.initials: J
authors.lastname: Kubelka
authors.forename: S
authors.initials: S
authors.lastname: Procházka
mesh_terms: D000328:Adult; D003188:Composite Resins; D003737:Dental Cavity Preparation / Q000295:instrumentation*; D003793:Dental Restoration, Permanent / Q000379:methods; D004871:Erbium; D005069:Evaluation Studies as Topic; D005260:Female; D005899:Glass Ionomer Cements; D006801:Humans; D053685:Laser Therapy; D008297:Male; D017063:Outcome Assessment, Health Care
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; D004871:Erbium