How is Age Determined for Dogs?

by Quentin Coleman
Your dog's smile tells you a lot about his life.

Your dog's smile tells you a lot about his life.

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Estimating your dog's age is a simple matter of looking him in the mouth. While it is impossible to determine exactly how old a dog is unless someone took the time to record his date of birth, there are a few indicators that allow you to make an educated guess.

Baby Teeth

Just like human babies, puppies aren't born with a full set of teeth. Young dogs don't have a complete set of adult teeth until they are 6 months old. Puppies start growing their first set of incisors two to three weeks after they are born. Their baby canine teeth emerge about a week later, possibly while their incisors are still growing. Baby molars start to grow when the dog is 4 to 6 weeks old. Your pup should have his whole set of baby teeth by the time he is 2 months old, according to Rural Area Veterinary Services.

Adult Teeth

You can figure out the age of an adolescent canine by looking at adult tooth emergence just like you can with puppies and their baby teeth. Young dogs start to grow their adult set of teeth when they are around 14 weeks old. Just like in puppies, young adults grow their incisors first, followed by canine teeth and molars. Permanent incisors are in by 4 months, while canines and a full set of molars start emerging in the weeks following, according to Found Animals. The full set of permanent teeth is in by the time the dog is 6 to 7 months of age.

Dental Hygiene

Since dogs have their permanent teeth early in their life, you can't rely on tooth emergence to determine a dog's age after 8 months. This is why vets and animal shelters look at the condition of your dog's teeth to estimate his age. If you ask your vet to determine how old your adult dog is, he can only make an educated guess based on how much tartar has built up so far. Clean, white teeth indicate a young adult between 1 and 3 years old. Significant tartar buildup on all teeth occurs in adult dogs between 3 and 5 years of age, while gum disease becomes apparent in dogs between 5 and 10 years old, according to Rural Area Veterinary Services. Severe dental deterioration, including rotting or missing teeth, is common in dogs over 10 years old.

Other Indicators

While a dental examination is the best way to get an idea of your dog's age, there are a few other things you can look for as well. As dogs enter the last few years of their life expectancy, which can vary significantly based on the breed, they show signs of muscle weakness and frequently develop fatty tumors. Eye problems like cataracts and joint pain from arthritis are also common in senior pups. Large dogs age much faster than small breeds. Great Danes could be considered seniors as early as 6, while a Pomeranian isn't a old man until about 13.

Photo Credits

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About the Author

Quentin Coleman has written for several news publications as well as the University of Delaware's public relations department. He also spent more than 10 years working with a local animal shelter to help nurse kittens, treat sick cats and domesticate feral animals. Coleman graduated from the University of Delaware with a bachelor's degree in journalism.

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