title: Adhesion forces between AFM tips and superficial dentin surfaces.
abstract: In this work, we study the adhesion forces between atomic force microscopy (AFM) tips and superficial dentin etched with phosphoric acid. Initially, we quantitatively analyze the effect of acid etching on the surface heterogeneity and the surface roughness, two parameters that play a key role in the adhesion phenomenon. From a statistical study of the force-distance curves, we determine the average adhesion forces on the processed substrates. Our results show that the average adhesion forces, measured in water, increase linearly with the acid exposure time. The highest values of such forces are ascribed to the high density of collagen fibers on the etched surfaces. The individual contribution of exposed collagen fibrils to the adhesion force is highlighted. We also discuss in this paper the influence of the environmental medium (water/air) in the adhesion measurements. We show that the weak forces involved require working in the aqueous medium.
authors.affiliation: Laboratoire PMCN, Université de Lyon, Université Lyon1 and CNRS, UMR 5586, F-69622 Villeurbanne, France.
authors.forename: I M
authors.initials: IM
authors.lastname: Pelin
authors.forename: A
authors.initials: A
authors.lastname: Piednoir
authors.forename: D
authors.initials: D
authors.lastname: Machon
authors.forename: P
authors.initials: P
authors.lastname: Farge
authors.forename: C
authors.initials: C
authors.lastname: Pirat
authors.forename: S M M
authors.initials: SM
authors.lastname: Ramos
mesh_terms: D000134:Acid Etching, Dental; D003094:Collagen / Q000737:chemistry; D003804:Dentin / Q000737:chemistry / Q000648:ultrastructure*; D006801:Humans; D018625:Microscopy, Atomic Force / Q000295:instrumentation; D008964:Molar, Third / Q000737:chemistry / Q000648:ultrastructure*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D003094:Collagen