Traditional classification of dental local anesthesia methods must be modified. In our current paper we have proved the vascular mechanism is the leading component of spongy injection. It is necessary to take into account the high effectiveness and relative safety of the spongy anesthesia. We must also take into account its versatility, ease of implementation and the growing prevalence in the world. The essence of the modification is to divide the anesthesia methods into two parts diffuse and vascular-diffuse.Diffuse anesthesia includes application, infiltration and conduction while vascular-diffuse includes intraosseous , intraligamentary , intraseptal and intrapulpal. For the last four methods we used the term spongy (intraosseous) anesthesia.