With the exception of direct electrical stimulation, it seems that all procedures known to produce dentinal pain may mechanically distort the structure of pain-sensitive nerves in the pulp and predentinal area and that this effect is mediated by a hydrodynamic link. Nature may contribute to insensitive dentin by: production of irregular, atubular dentin at the pulpal wall; obliteration of dentinal tubules by sclerosis; and mineralization of a superficial layer, pellicle or plaque, at the exposed surface. Few clinical methods are capable of accelerating these mechanisms. A technique of resin impregnation for the desensitization of exposed dentin has been presented. After proper pretreatment, that includes drying the dentin surface, resin tags can be obtained in the outer part of the dentinal tubules and may immediately and permanently relieve dentinal pain. This technique seems to be a good alternative to other methods, especially for patients with occlusal or incisal exposures caused by abrasion, grinding, or fracture, in which other methods cannot provide immediate and long-lasting desensitization.