In clinical dentistry, since fracture is a major cause of tooth loss, better understanding of mechanical properties of teeth structures is important. Dentin, the major hard tissue of teeth, has similar composition to bone. In this study, we investigated the mechanical properties of human dentin not only in terms of mineral density but also using structural and quality parameters as recently acc...

This study compared the tubular dimensions and distribution of human and bovine dentin. Ten human molars and 10 bovine incisors were ground with a high-speed handpiece to obtain 3 sections at different dentin depths (superficial, middle and deep). The specimens were sputter-coated with gold to be examined under scanning electron microscopy (SEM). Three SEM micrographs were recorded randomly for...

In recent years, substantial progress has been made regarding the molecular etiology of human structural tooth diseases that alter dentin matrix formation. These diseases have been classified into two major groups with subtypes: dentin dysplasia (DD) types I and II and dentinogenesis imperfecta (DGI) types I-III. Genetic linkage studies have identified the critical loci for DD-II, DGI-II, and D...

Introduction: Dentin hypersensitivity is a pain arising from exposed dentin, typically in response to clinical, thermal, tactile, evaporative or osmotic stimuli that cannot be explained as arising from any other form of dental pathology. Most authorities agree that Brannstrom’s “Hydrodynamic Theory" of nerve stimulation due to movement of dentinal fluid, best explains dentin hypersensitivity. T...

In vitro tensile bond strengths of Photo Clearfil Bright (PB) and Clearfil Photo Posterior (CP) with Clearfil Photo Bond to human enamel and dentin were determined by a truncated cone bond test. Parameters tested were: four substrates (etched enamel; unetched dentin, D1; dentin conditioned with 10% polyacrylic acid, D2; and dentin etched with phosphoric acid, D3); two techniques (bonding agent ...

In comparison to enamel, bonding to normal dentin is a greater challenge because of its organic constituents, fluid-filed tubules, and variations in intrinsic composition. Bonding to sclerotic dentin is even more difficult. To evaluate the shear bond strengths of four adhesive systems to dentin substrates with different levels of mineralization, 120 extracted human teeth were randomly assigned ...

Previous studies have shown a wide range of pulpal reactions to dentin bonding systems and a poor correlation between in vitro and in vivo toxicity of dentin bonding agents. Because dentin bonding agents are composed of multiple components which may diffuse through dentin, we hypothesized that these components may cause cytotoxicity through interactive (synergistic) effects. We investigated the...

Light propagation in human dentin exhibits a strong directional dependence featuring the long-known optical magnification property. We hypothesized that this anisotropic effect is caused by multiple scattering at the dentin tubules, and not by fiberoptic effects, as had been previously assumed. We performed measurements of the transmitted intensity from dentin disks and compared them with Monte...