Treatment of dentin hypersensitivity with stannous fluoride: a scanning elctron microscopy study and dentin permeability evaluations

Dentin hypersensitivity in caused by open dentinal tubules which increase permeability. In remains a serious clinical problem, since attempts to deal with in have only been partly successful. One recent form of treatments is stannous fluoride gel (GELKAM, Colgate).
The present study is intended to evaluate the electron microscope picture (SEM) of morphology of the dentin surface with and without smear layer (removed with acid solution) and the degree of dentin permeability. The latter in considered the main indicator directly correlated to the degree of dentin sensitivity and to morphology. Dentin permeability was studied with a hydraulic apparatus working at 1.0 psi pressure, equal approximately 70 cm of water. Stannous fluoride gel reduced dentin permeability and changed smear layer morphology, with the formation of a thick, compact layer. This study confirms in vitro the ability of Gel Kam to reduce dentin sensitivity in vivo.