[Longevity of amalgam fillings in permanent teeth of minors]

The longevity of 3,300 amalgam fillings was tested with 1,165 juvenile minors at the age of 16 to 17, born in 1967-69. Up to the closing of peadontic care it was necessary to renew 25 percent of all amalgam fillings once or several times. After a manual trituration the renewing rate was more than the double of hight. Fillings applied between 6 and 9 years of life must be renewed to 37 percent during 5 years; fillings applied between 9 and 11 years of life were renewed to 25 percent. Differences between fillings applied at the High School and in the territory, respectively, have not been registered.