title: Determination of elastic modulus of demineralized resin-infiltrated dentin by self-etch adhesives.
abstract: The purpose of this study was to determine ultrasonically the changes in elastic modulus of demineralized adhesive-infiltrated dentin. Dentin disks were obtained from bovine incisors and shaped into a rectangular form. The specimens were immersed in single-step self-etch adhesives, then stored in distilled water and run through thermal cycles between 5 and 60 degrees C. The longitudinal and shear wave sound velocities and the elastic modulus were determined using ultrasonic equipment composed of a pulser-receiver, transducers, and an oscilloscope. After 24 h of storage, the elastic modulus of mineralized dentin was 16.9 GPa and that of demineralized dentin was 2.1 GPa. The immersion of demineralized dentin in adhesives significantly increased the elastic modulus to 3.3-5.9 GPa. After 30,000 thermal cycles, the elastic modulus of dentin was 32.4 GPa, whereas that of demineralized adhesive infiltrated dentin was 3.1-4.1 GPa. Thermal stresses did not cause adhesive-infiltrated demineralized dentin to deteriorate, as measured by elastic modulus.
authors.affiliation: Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan.
authors.forename: Genta
authors.initials: G
authors.lastname: Yasuda
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Inage
authors.forename: Toshiki
authors.initials: T
authors.lastname: Takamizawa
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Kurokawa
authors.forename: Akitomo
authors.initials: A
authors.lastname: Rikuta
authors.forename: Masashi
authors.initials: M
authors.lastname: Miyazaki
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000269:Adhesives; D000818:Animals; D002417:Cattle; D003799:Dental Stress Analysis; D003804:Dentin / Q000737:chemistry; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents; D004548:Elasticity; D006358:Hot Temperature; D008689:Methacrylates; D019279:Resin Cements; D017001:Tooth Demineralization / Q000473:pathology*; D014465:Ultrasonics
chemical_list: C514346:Absolute adhesive; D000269:Adhesives; C515604:Clearfil Tri-S Bond; D017220:Dentin-Bonding Agents; C498353:G-Bond; D008689:Methacrylates; D019279:Resin Cements