Changes in Rat Incisors Resulting from Trauma on the Pulp

¹ Departments of Pathology, and Periodontics and Endodontics, The Hebrew University—Hadassah Medical School and the Hadassah School of Dentistry, Jerusalem, Israel

The effect of pulp damage on the incisors of 39 rats was studied. The animals were divided into three groups: in the first, the lower incisors were cut at gingival level; in the second group, in addition, the pulp was damaged with a dental reamer; and in the third, a permanent mechanical irritant was also left in the pulp.

The experiment showed that growth was unimpaired in the first group; in the second, increased, diminished, delayed or totally inhibited eruption was seen. Similar changes were observed in the third group, where complete inhibition of eruption was more frequently seen. Histologic changes occurred in the teeth and their surrounding tissues whenever eruption was retarded or inhibited altogether.