Underdeveloped facial bones at birth resulting in an overbite or an underbite is now unfortunately a common birth defect. The underdeveloped bones appear to be the result of specific disruptions to the bone growth during fetal development. Many wild and domestic mammals and birds and little children (prior to cutting the adult teeth) have had the underdeveloped bone or bones stimulated to grow to be normal in size resulting in a normal bite. It takes about two weeks for a fairly severe underbite to grow to be normal on a newborn grazing animal. It takes only two or three days for the upper facial bones to grow to normal on a hatchling bird. This only works on birds prior to them becoming fully grown fledglings. It only works on children while they are still growing fairly fast - best when the child is very young. All you have to do is give one tablet of a Homeopathic Cell Salt called Calc. Phos. 30X to the newborn mammal (including human child) or bird morning and night (three times a day results in faster growth) and the underdeveloped facial bones will grow to normal if the problem is an epigenetic change during development. If the problem is actually genetic like everyone says it alway is, the bones can't be stimulated to grow to normal because they are genetically programmed to be the way they are. Most underbite and overbite birth defects on vertebrate species in the last 20 years are cause by epigenetic changes during development and thus can be stimulated to grow to normal.