Retained Deciduous Teeth
The deciduous (baby or temporary) teeth are smaller than the permanent teeth. As the animal grows and the jaw becomes larger, the baby teeth are shed. Normally, the baby tooth is lost before the permanent tooth appears. Occasionally, the root of a baby tooth is not resorbed and the tooth remains "anchored" within the tooth socket. Retention of baby teeth favors tartar accumulation, which may lead to more serious gum disease. Also it may cause an abnormal bite (malocclusion), extreme pain and or dental abscesses. For this reason, retained baby teeth should be extracted as early as possible.
The deciduous (baby or temporary) teeth of dogs erupt (appear) as early as 2 weeks of age, and all 28 temporary teeth should be visible by 8 weeks of age. After 8 weeks of age, shedding of the temporary teeth begins and continues until around 6 months of age. All adult or permanent teeth should be in full view by 8 months of age.
The deciduous teeth of cats erupt as early as 2 weeks of age, and all 26 temporary teeth should be visible by 7 weeks of age. By 7 months of age, all 30 permanent teeth should be in full view.