Experimental enlargement of submandibular salivary glands of rats

Abstract

An increase of 12% in fresh and dry weight of the submandibular salivary glands was observed 24 hours after a single amputation of the lower incisor teeth. The effect of repeated amputations was increased by increasing the frequency of amputations and by lengthening the period of amputations. After cessation of a series of amputations, the weight of the hypertrophied salivary glands decreased gradually to approach the control level. Repeated amputation of only one lower incisor tooth was much less effective than amputation of both, and the effect was largely but not entirely restricted to the ipsilateral glands. Ulceration of the adjacent mucosa without amputation of the incisors had no detectable effect on the salivary glands. After amputation of the tips of the incisor teeth without exposure of the pulp or after half-amputations with minimum exposure, the salivary glands increased in weight significantly but much less than after amputation at the gingival margin. It is concluded that the data support the reflex neurological explanation of the phenomenon previously offered by the authors.