Dogs rarely complain about their teeth, so dental problems usually surface through smell, sight, and changed eating rather than obvious pain. The mouth you can check at home — lips lifted, gums visible, back teeth glimpsed when he yawns or pants — shows a surprising amount. Healthy gums are smooth and pink (or pigmented in some breeds) and meet clean tooth edges. When tartar, gum inflammation, or a damaged tooth develops, the changes are visible weeks before a dog stops eating, which is why a regular look inside the mouth is worth building into grooming time.
What you will smell and see first
Persistent bad breath that goes beyond normal dog breath is the most common early flag, because bacteria flourishing along the gumline produce that sour, rotten odor. Look for yellow or brown crusty buildup, especially on the large upper back teeth and canines, a red line where gum meets tooth, gums that bleed when he chews a toy or when you brush, and any gum swelling, lump, or area where the gum has pulled away and exposed part of a root. A tooth that looks gray, pink-tinged, chipped, or noticeably looser than its neighbors also counts, even if he is still eating happily.
Eating and behavior changes that point to the mouth
A sore mouth changes mechanics before it changes appetite. Watch for a dog who approaches his bowl eagerly, then eats hesitantly, drops pieces of kibble, tilts his head to chew on one side, or switches himself to the softest food available and leaves hard biscuits. Some dogs paw at their muzzle, rub their face along the carpet, drool more on one side, or become head-shy about having their muzzle handled — a new reluctance in a dog who previously tolerated it. Less obvious still, a dog with chronic mouth discomfort may simply play less with chew toys and seem quieter overall.
Checking safely at home, breed by breed
Make the check brief and paired with something pleasant: lift each lip for a few seconds, look along both upper tooth rows, then reward him and stop. Flat-faced breeds crowd teeth into a small jaw and build tartar quickly, small breeds are notably prone to gum disease and retained baby teeth, and older dogs of any size accumulate problems, so these dogs deserve the most regular looks. Never force a painful mouth open, and stop if he growls or snaps — that reaction itself is information for your veterinarian. Note what you saw, even roughly: which side, which teeth, whether gums bled.
When a dental sign needs a prompt appointment
Book a veterinary visit if you see a broken or loose tooth, facial swelling, bleeding that does not settle, a lump on the gum, refusal to eat, or signs of pain such as crying when yawning or chewing. A swelling below the eye in particular can be linked to an upper tooth root and should not be watched at home for weeks. Mouth problems rarely improve on their own, and gum disease progresses under the gumline where you cannot see it, so an examination under proper light — and sometimes with him sedated — is how the real extent is judged.
Keeping a mouth history alongside his health records
Because dental change is slow, dated notes beat impressions: tartar heavier on the left, lower canine chipped, breath worse since spring. Those observations, plus records of cleanings and any teeth removed, tell the next clinician what has already happened in this mouth and what to watch. Keeping that dental timeline in KinsLe's Pet Passport, together with his other health records in one packet, means nothing about his teeth relies on you remembering which year the back tooth came out.