title: Evaluation of thermal stress in hydroxyapatite film fabricated by powder jet deposition.
abstract: This study aimed to create a thick hydroxyapatite (HA) film on the surface of a human tooth via a powder jet deposition (PJD) device for dental handpieces, and to examine the microstructural and mechanical properties of the HA film. In particular, the effects of thermal stress on this film were evaluated. The HA film was created by blasting 3.18-μm HA particles, calcinated at 1,200°C, onto the enamel substrate at room temperature and atmospheric pressure. An HA film with an area of 3 mm × 3 mm was prepared and polished. The following HA film parameters were evaluated from the three-dimensional surface profile: surface roughness, Vickers hardness, and bonding strength before and after artificial aging induced by 500 cycles of thermal cycling (5-55°C). The HA particles in the deposited film were densely packed, and the surface of the HA film was unchanged after thermal cycling. There were also no significant differences in the hardness and the bonding strength of the HA film before and after thermal cycling. The HA film created in this study demonstrated excellent microstructural and mechanical properties, even after the application of thermal stress.
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Akatsuka
authors.forename: Ken
authors.initials: K
authors.lastname: Matsumura
authors.forename: Miyoko
authors.initials: M
authors.lastname: Noji
authors.forename: Tsunemoto
authors.initials: T
authors.lastname: Kuriyagawa
authors.forename: Keiichi
authors.initials: K
authors.lastname: Sasaki
mesh_terms: D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003743:Dental Enamel / Q000737:chemistry*; D003748:Dental Equipment; D003764:Dental Materials / Q000737:chemistry*; D017886:Durapatite / Q000008:administration & dosage / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008964:Molar, Third; D010316:Particle Size; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D003764:Dental Materials; D017886:Durapatite
keywords: hydroxyapatite; interface; powder jet deposition; thermal stress