It is normal for a baby to not have any teeth by one week old. The development of primary teeth begins in the fetal stage, with the tooth buds forming in the baby’s upper and lower jawbones, containing 20 primary teeth. At birth, these tooth buds only have crowns without roots, which develop gradually after birth. Typically, babies start growing primary teeth around six months old, starting with the lower front teeth, followed by the upper front teeth. By around two and a half years old, all 20 primary teeth should have grown out. There is no need to worry at this stage. Wishing your baby a healthy growth.