Observations on Electrical Pulp Testing

In present day clinical practice, the chief purpose of pulp testing is to determine whether or not a pulp is normally vital. If not, it is desirable to ascertain to what degree degenerative processes have progressed. When degeneration has advanced to the point of necrosis, the resultant destructive action may often be easily determined in a radiographic study of apical and periapical tissue. The danger in the radiograph as an instrument of evidence, however, lies in its limitations; e.g., anatomical structures in bone and bone pathoses superimposed upon the shadow of the apex, which may or may not be associated with non-vital teeth, are open to misinterpretation. Moreover, the amount of other harmful change in the pulp, as well as necrosis not definitely ascertained clinically or radiographically, clearly demand a means of identification. For this differential diagnosis, various methods have been devised. Many are based upon physiological principles of nerve stimulation through the use of electrical devices. Thus far, however, the available equipment of this nature, in our opinion has not been wholly satisfactory. It is our object in this discussion to analyze and evaluate methods and apparatus which we have used in an attempt to overcome some existing shortcomings, and to scrutinize these in the light of their efficiency as a source of more accurate information as to the condition of the pulp.