title: Intrapulpal temperature changes during root surface irradiation with dual-wavelength laser (2780 and 940 nm): in vitro study.
abstract: This work reports that the ablation volume and rate of porcine skin changed significantly with the change of skin water content. Under the same laser irradiation conditions (532 nm Nd:YAG laser, pulse width = 11.5 ns, pulse energy = 1.54 J, beam radius = 0.54 mm), the ablation volume dropped by a factor of 4 as the skin water content decreased from 40 wt. % (native) to 19 wt. % with a change in the ablation rate below and above around 25 wt. %. Based on the ablation characteristics observed by in situ shadowgraph images and the calculated tissue temperatures, it is considered that an explosive rupture by rapid volumetric vaporization of water is responsible for the ablation of the high water content of skin, whereas thermal disintegration of directly irradiated surface layer is responsible for the low water content of skin.
authors.affiliation: RWTH Aachen University Hospital, Department of Conservative Dentistry, Periodontology, and Preventive Dentistry, Pauwelsstrasse 30, 52074 Aachen, Germany.
authors.forename: Rene
authors.initials: R
authors.lastname: Franzen
authors.affiliation: RWTH Aachen University Hospital, Department of Conservative Dentistry, Periodontology, and Preventive Dentistry, Pauwelsstrasse 30, 52074 Aachen, Germany.
authors.forename: Borna
authors.initials: B
authors.lastname: Rashidisangsary
authors.affiliation: Biruni University, Faculty of Dentistry, Department of Periodontology, Topkapi 34010, Istanbul, Turkey.
authors.forename: Seda
authors.initials: S
authors.lastname: Ozturan
authors.affiliation: RWTH Aachen University Hospital, Department of Conservative Dentistry, Periodontology, and Preventive Dentistry, Pauwelsstrasse 30, 52074 Aachen, Germany.
authors.forename: Leon
authors.initials: L
authors.lastname: Vanweersch
authors.affiliation: RWTH Aachen University Hospital, Department of Conservative Dentistry, Periodontology, and Preventive Dentistry, Pauwelsstrasse 30, 52074 Aachen, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Gutknecht
mesh_terms: D001831:Body Temperature / Q000528:radiation effects*; D003782:Dental Pulp / Q000528:radiation effects*; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects* / Q000295:instrumentation; D007834:Lasers; D016745:Root Planing / Q000009:adverse effects* / Q000295:instrumentation; D014092:Tooth Root / Q000528:radiation effects