Woods Hutchinson,
A Handbook of Health
“ In our mouths, at about seven years of age, a larger, heavier tooth pushes up behind the last milk tooth,—called the "seventh year molar,"—the milk teeth begin to loosen and fall out, and their places are taken by other new teeth budding up out of the jaw just as the first set did. These take a still longer time to grow, so that the last four of the full set of thirty-two do not come through the gums until somewhere between our eighteenth and twentieth years. ”
