Experimental Production of Apical Lesions of Teeth in Monkeys, and Their Relation to Systemic Disease *

In an investigation designed to determine the relation of apical infections of teeth to systemic disease, one important phase of the program was a correlation of the bacteriological, roentgenological, and anatomical findings of the teeth with the clinical course and the lesions observed in man at post mortem. Details of the methods used and some of the results have been published by Burket.' Studies were also made in healthy, mature monkeys whose teeth were infected either by exposing the pulp canal to the oral flora or by sealing known strains of organisms into the pulp chamber. The clinical course and the development of the dental lesions were followed for various lengths of time; the procedure used for the examination of the teeth and organs at necropsy was that used with man. Fifteen monkeys were used in these experiments. The teeth of 11 animals had had the pulp exposed to the oral cavity; in 4 monkeys known bacteria were introduced into the pulp chambers. The material studied consisted of 98 roots from 56 teeth with pulp exposure, and 22 roots from 13 teeth in which bacterla had been sealed into the pulp. Controls consisted of 18 roots from 16 teeth that had not been operated upon. In 10 teeth with single roots, sterile saline was introduced into the pulp chamber; these served as controls for the operative procedure. From 8 to 15 teeth of a single animal were included in an experiment.