First his lower central incisor fell, then the upper central incisor, then the lower first molar (both) was pushed out by teeth under them. Now his lower lateral incisors have fallen (within two weeks from each other). I notice while they were loose the gum under them were brown. The lower left lateral fell first. When the lower right lateral fell (today 07/27/10) he complained that it hurt. Both teeth are fine no discoloration. The gum is still brown. Should i be worried?