Mechanical and leakage behaviour of the dentin--adhesive interface.
Dentine bonding systems (DBS) have been developed in order to bond restorative materials (i.e. composite) to the inner walls of the tissues when function and integrity as to be restored. Adhesion to dentine results from the penetration of DBS into the demineralised substrate constituted by a swollen collagen network. The short-term stability of a restored tooth is mainly affected by the presence of defects which act as stress raiser, while the long-term stability of a restored tooth is mainly affected by the seal of the restorative material on the dental structures. In order to determine the properties of the material interface, bonding to dentine is analysed using micro-tensile static and dynamic tests, assisted by the finite element modelling (FEM) and by the X-ray computed microtomography (micro-CT). The effect of voids and porosity in the composite layer of the DBS on the stress distribution has been investigated. Tensile adhesive strength for a particular DBS was measured on cylindrical specimens. The dual energy absorption technique, with the synchrotron beam light, has been developed to investigate, in a non-destructive manner, the leakage at the dentine-DBS interface of a silver nitrate staining solution as a function of mechanical cycling. The results indicate that leakage occurs radially through the dentine-adhesive interface and is influenced by the porosity in the adhesive and composite layers.
Mollica
Francesco
F
Department of Materials Engineering, University of Ferrara, Via Saragat 1, 44100 Ferrara, Italy.
De Santis
Roberto
R
Ambrosio
Luigi
L
Nicolais
Luigi
L
Prisco
Davide
D
Rengo
Sandro
S
D002484:Cementation / Q000379:methods*; D003198:Computer Simulation; D003804:Dentin / Q000737:chemistry* / Q000502:physiology*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing / Q000379:methods*; D008954:Models, Biological; D008964:Molar, Third / Q000737:chemistry / Q000502:physiology*; D016062:Porosity; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
D017220:Dentin-Bonding Agents