Abstract
Although fluorine was first isolated in 1886 by Moissan, its human toxicity as manifested in the mottled teeth incidence was first reported by J. M. Eager. The study of the disease was further followed up by G. V. Black and F. S. Mckay, from whom the name, mottled teeth, was originated. Fukui and Tomitori were among the earliest investigators of our country in the study of this problem. During two years period from 1958 to 1959, we conducted a survey on the mottled teeth incidence among children of Tobata city primary schools, with respect to rate of occurrence, number of teeth involved, susceptibility of individual teeth, classification of the disease severity and also to the possible relation of mottled teeth to dental caries incidence. The results obtained are summarized as follows. 1) The mottled teeth incidence amounted to 2% in the average among whole subjects examined, of which it was low in the lower class and high in the higher class of children. 2) Most frequently a single tooth among the dentition was attacked by mottling, and accordingly, multiple mottled teeth incidence was lowered with increasing number of teeth attacked. 3) On classifying the mottled teeth by severity, there were 99.7% of M1 and 0.3% of M_3B found, with no intermediate severity. The mottled teeth with M_1 severity allowed to be further classified by their forms into dotted, linear, striped and speckled.
