Do adult dog teeth grow back?

Adult dog teeth do not grow back. Dogs have two sets of teeth in their lifetime: deciduous teeth and permanent teeth. Deciduous teeth, also known as puppy teeth, start to appear around 2-3 weeks of age and are all usually present by 6 months. Permanent teeth start to erupt around 3-4 months of age and are all usually present by 6-7 months. Once a permanent tooth has erupted, it will not be replaced if it is lost.