Periodontal terminology revisited.

The body of knowledge that was the basis of the science and therapy of periodontics can be found in the literature of the 1950s and 60s. This information conveniently was presented in various textbooks. The evolution of research utilizing histochemistry and electron microscopy, along with disciplined clinical studies, has resulted in an exponential increase in information. A by-product of this worldwide effort is confusion resulting from the misuse and interchangeable application of terms disregarding the definitions originally accepted. Even with workshops designed in part to arrive at consensus to preclude confusion, the literature is replete with misleading use of nomenclature. The lack of attention to the appropriate use of terms is, at best, confusing to the student, researcher, and clinician. In the worst case, it may result in poor performance on examinations and improper evaluation of techniques and materials. Many periodontal terms are used inappropriately or are not completely understood, probably because these words have not been adequately described in the literature. Some of the more commonly used and confused terms will be discussed using literature to support the definitions.