title: Imaging of Dental Hard Tissue Surfaces Prepared by an Ultrashort Pulsed Laser System (USPL).
abstract: The aim of this study was to compare surface structures of laser-irradiated dental hard tissues using confocal (CFM), atomic force (AFM), and scanning electron microscopy (SEM). The general potential of the AFM in analyzing laser-irradiated surfaces was determined in this context. Specimens of human enamel and dentin were irradiated using an 8.6 W Nd:YVO4 laser with a pulse duration of 8 ps, λ Center=1,064 nm, and a pulse repetition rate of 500 kHz. Surface topology of irradiated areas (1 mm2) was investigated using AFM, CFM, and SEM. Surface roughness R z was measured only with the AFM and the CFM. For non-irradiated enamel and dentin surfaces, roughnesses for CFM and AFM are in the nanometer range. However, major differences in roughness were determined for laser-prepared surfaces. For enamel, R z (CFM)=2.33 μm is much higher compared with R z (AFM)=0.09 μm; in the case of dentin, R z (CFM)=5.35 μm is also much higher compared with R z (AFM)=0.093 μm. Information regarding structural properties of surfaces needs real dimensions, particularly for use in dentistry. In this respect, AFM technology provides no additional results that lead to a significant improvement.
authors.affiliation: 1Department of Operative and Preventive Dentistry, Dental Faculty,Bonn University,53111 Bonn,Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schäper
authors.affiliation: 2Oral Technology, Dental Faculty,Bonn University,53111 Bonn,Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Reimann
authors.affiliation: 1Department of Operative and Preventive Dentistry, Dental Faculty,Bonn University,53111 Bonn,Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Frentzen
authors.affiliation: 1Department of Operative and Preventive Dentistry, Dental Faculty,Bonn University,53111 Bonn,Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Meister
mesh_terms: D003743:Dental Enamel / Q000528:radiation effects* / Q000648:ultrastructure*; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure*; D006801:Humans; D007834:Lasers; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties
keywords: dentin; enamel; imaging methods; surface topology; ultrashort pulsed laser