Pulp Degeneration

Although degeneration of the pulp, as such, is seldom recognized clinically, the types of pulp degeneration should be included in a description of diseases of the pulp. Degeneration is generally present in the teeth of older people. Degeneration may also be the result of persistent, mild irritation in teeth of younger people, however, as in cal­cific degeneration of the pulp. Degeneration is not necessarily related to infection or  car­ies, although a cavity or filling may be pres­ent in the affected tooth. The early stage of pulp degeneration does not usually cause definite clinical symptoms. The tooth is not discolored, and the pulp may react normally to electric and thermal tests. As degeneration of the pulp progresses, the tooth may become discolored, and the pulp will not respond to stimulation. The specific types of pulp de­generation are discussed in the following paragraphs

Calcine Degeneration. In calcine degen­eration, part of the pulp tissue is replaced by calcific material; that is, pulp stones or denticles are formed. This calcification may occur either within the pulp chamber or root canal, but it is generally present in the pulp chamber. The calcified material has a laminated structure, like the skin of an onion, and lies unattached within the body of the pulp. Such a denticle or pulp stone may become large enough to give an impression of the pulp cavity when the calcified is removed in another type calcifi­cation, the calcified material is attached to the wall of the pulp cavity and is an integral part of it. It is not always possible to distinguish one type from another on a radiograph.

It is estimated that pulp stones are present in more than 60% of adult teeth. They are considered to be harmless concretions, al-though referred pain in a few patients has been ascribed to the presence of these calcifications in the pulp.

Teeth with pulp stones have also been suspected of being foci of infection by some clinicians. No difference has been found in incidence of pulp stones between a group of arthritic patients and a normal control group of approximately the same ages.⁹⁸ The reader should refer to Chapter 3 for further information on and illustrations of calcification.

Atrophic Degeneration. In this type of de-generation, observed histopathologically in pulps of older people, fewer stellate cells are present, and intercellular fluid is increased. The pulp tissue is less sensitive than normal. So-called "reticular atrophy" is an artifact produced by delay of the fixative agent in

reaching the pulp and should not be con-fused with atrophic degeneration. No clinical diagnosis exists.

Fibrous Degeneration. This form of degen­eration of the pulp is characterized by replacement of the cellular elements by fibrous connective tissue. On removal from the root canal, such a pulp has the characteristic appearance of a leathery fiber (Fig. 4-11). This disorder causes no distinguishing symptoms to aid in the clinical diagnosis.

Pulp Artifacts. Vacuolization of the odontoblasts was once thought to be a type of pulp degeneration characterized by empty spaces formerly occupied by odontoblasts. It is probably an artifact caused by poor fixation of the tissue specimen. Fatty degeneration of the pulp, along with reticular atrophy and vacuolization, are all probably artifacts with the same cause, that is, unsatisfactory fixation.