title: Temperature rise during Er:YAG and Nd:YAP laser ablation of dentin.
abstract: This in vitro study compared temperature rises during cavity preparation with an Er:YAG laser, Nd:YAP laser, and a high-speed handpiece. Eighteen teeth were sectioned longitudinally and divided into six groups: group 1 was treated with a carbide bur on a high-speed dental handpiece; group 2 was treated with an Er:YAG laser with an energy of 140 mJ, a pulse repetition rate of 4 Hz; and group 3 was treated with an Nd:YAP laser with an energy of 240 mJ, a pulse repetition rate of 10 Hz. In these groups no water cooling was used. Groups 4 to 6 were treated in the same way, but with water spray. Temperature increases were measured at different dentin thicknesses by a microthermocouple attached to the inner side of the pulp chamber. Water cooling was essential to reduce temperature effects in all groups. Nd:YAP laser induced significantly higher temperature rises than Er:YAG or handpiece. Temperature response to the Er:YAG laser and the handpiece seemed to be similar.
authors.affiliation: Centre de Recherche Interdisciplinaire sur les Tissus Calcifiés et les Biomatériaux, Nantes, France.
authors.forename: V
authors.initials: V
authors.lastname: Armengol
authors.forename: A
authors.initials: A
authors.lastname: Jean
authors.forename: D
authors.initials: D
authors.lastname: Marion
mesh_terms: D000538:Aluminum Silicates; D000704:Analysis of Variance; D001831:Body Temperature / Q000528:radiation effects*; D003737:Dental Cavity Preparation / Q000295:instrumentation; D003754:Dental High-Speed Equipment; D003782:Dental Pulp / Q000502:physiology; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure; D004867:Equipment Design; D004871:Erbium; D006801:Humans; D053685:Laser Therapy; D008904:Miniaturization; D009354:Neodymium; D018709:Statistics, Nonparametric; D013821:Thermometers; D014867:Water; D015019:Yttrium
chemical_list: D000538:Aluminum Silicates; D014867:Water; D009354:Neodymium; D015019:Yttrium; D004871:Erbium