Final answer:
The permanent incisors of a dog usually erupt at around 18-22 weeks of age, replacing the deciduous incisors.
Step-by-step explanation:
The permanent incisors of a dog usually erupt at around 18-22 weeks of age.
Dogs have a total of 6 permanent incisors - 3 on each side of the upper and lower jaw. The permanent incisors replace the deciduous (baby) incisors and serve important functions in biting and tearing food.
It's important to note that there can be variations in the exact timing of tooth eruption between individual dogs, so it's best to consult a veterinarian to monitor your dog's dental development.