The tooth replacement period for dogs usually occurs when the dog is 3-6 months old, and all teeth should be completed by six months. Because the deciduous teeth are falling out and the new permanent teeth are about to emerge, there will be discomfort at this time, and the dog will bite things to slow down and help the teeth grow smoothly. In addition, during the teeth changing period, dogs need to supplement nutrients, especially calcium. If there is a lack of calcium during the teeth changing period, the previous deciduous teeth will not fall out easily, and it will be difficult for the new teeth to grow. Therefore, it is found that the dog needs to supplement calcium and other nutrients in time when the teeth are changing. .