DHYG 140 Chapter Notes - Chapter 3: Local Anesthesia, Dental Anesthesia, Endodontics
Document Summary
Anesthetic agents, like any other medication, should not be administered without complete knowledge of the patient"s medical and dental history. Adverse and allergic reactions should be investigated during previous administrations. Injectable local anesthetics commonly used are weakly basic in nature and poorly soluble in water. To make them of clinical utility they are combined with hydrochloric acid to form hydrochlorides, which are soluble in water and acid reaction. When diluted, salts of local anesthetic compounds exist in two forms: an uncharged molecule (rn) and a positively charged cation (rnh +). The relative portion of each will depend on the ph of the solution in the cartridge and in the tissues and the pk of the specific anesthetic compound. Pk is the ph value at which a compound contains the same amount of non-ionized molecules and ionized cations. Agent pk approximate time for initiation of the action (min. )
