Abstract
Oral health status and cause of tooth loss were studied in 1060 mentally retarded individuals who were admitted and resided in an institute during the period of 1971-1988. Our study cohort comprised 7-14 % of the estimated total of profoundly to moderately retarded persons in the general population. The estimate was nearly 10 thousand among the approximately 2.5 million general population of Niigata Prefecture throughout 1971 to 1988. A higher mean tooth loss was associated with increasing age : 1.2 in 6-14-year-olds and 6.6 in 35-44-year-olds in the 1970's, and 0.7 in 6-14-year-olds and 9.1 in 45-54-year-olds in the 1980's. These values were approximately 2-4 times higher in all ages but more than 15 times in 6-14-year-olds and in the 1980's diminished a bit in 45-54-year-olds than the values in the general population. Age and caries experience (DMFT) have been statistically proved to be significant risk indicators or factors of severer tooth loss in all ages through the life of mentally retarded persons.
