Changes in oral health from 1973 to 1982 of 13-15-year-old schoolchildren residing in three different fluoride areas in Finland.

The aim of the present study was to analyze the change from 1973 to 1982 in the oral health conditions of 13-, 14-, and 15-year-old school-children residing in three different fluoride areas in Finland. Oral hygiene, as measured with the Visible Plaque Index (Ainamo and Bay, 1975), had improved significantly both among 13-year-old girls (P less than 0.01) and among boys of the same age (P less than 0.05). A highly significant improvement (P less than 0.001) of gingival health, as measured with the Gingival Bleeding Index (Ainamo and Bay, 1975), was observed for boys but not for girls. The striking change was for the DFST (T = total) and FSAA (A = approximal) scores for the totals of 180 girls and 180 boys. This improvement in dental health was mainly due to a dramatic decline of caries in the low-fluoride (0.2 ppm F) area, whereas in the high-fluoride area (2.5 ppm F), the improvement in oral hygiene and gingival health was the greatest. The results support earlier assumptions that caries and gingivitis are separate and mutually independent disease entities. The study further suggests that local fluoride treatments can provide caries-preventive benefits similar to those achieved by community water fluoridation, although at greater cost. The comparison in time revealed that most of the differences in oral health, observed in 1973 both between sexes and between the different fluoride areas, had disappeared by the time of the 1982 examination.