Let me qualify what I just wrote with this excerpt from Price's book: << Two serious defects from which many individuals in our modernized civilization suffer are impacted teeth and the absence of teeth due to their failure to develop. It is significant that in the arches of the primitive races practically all teeth form and erupt normally, including the third molars. In the modernized primitives and among our modern whites with deformed dental arches many teeth are impacted and often several of the permanent teeth have never formed. The evidence indicates that this, like the facial and dental arch deformities is due to an absence of vitamin A in the diet of the mother during the gestation period or of one or both of the parents prior to conception. >> David