Dental Disease Stages for Dogs 

Periodontal disease is the most common clinical disease in pets, affecting 8 out of 10 dogs over the age of three. It is a condition of the gum tissue caused by plaque and tartar buildup on the teeth, especially below the gum line. Fortunately, periodontal disease is preventable with basic care and regular veterinary checkups.

If your dog is over three years old and has not had proper dental care, they may already have periodontal disease. Even though it may not seem like a big problem at first, periodontal infections can lead to more serious health problems.

Periodontal disease is completely reversible in pets if it is not too advanced, so it is important to recognize it early. This disease has four stages, each with its own signs and symptoms.

If you notice any signs of periodontal disease in your dog, such as bad breath, red or swollen gums, or loose teeth, schedule a dental cleaning right away. Early treatment can help to prevent serious health problems and keep your dog’s mouth healthy.

Healthy Mouth

Healthy dog gums resemble healthy human gums in many ways. Typically, a healthy dog's gums appear bubble-gum pink or even salmon pink. It's important to note that some dog breeds naturally have dark-colored or spotted gums, which can be perfectly normal for your pet. However, if you notice a change in your dog's gum color over time, it may be a cause for concern.

Normal dog gums are moist and have a slippery texture. There should be no noticeable odor when you approach your dog's mouth, and you should not observe any swelling, lumps, or bumps.

Notice there is bone reaching all the way to the crown of the tooth, indicating NO bone loss.

Notice how gums have a sharp edge and lay flat against the tooth.  This is healthy gums look.

Action plan for healthy mouths:

Small dogs and cats with healthy mouths should have COHAT annually.  Larger dogs every year or two.  Time between dental cleanings is dependent on how much Preventative Dental Care is done at home.  Our Home Preventative Dental Care recommendations are here:  Home Preventative Dental Care  

First Stage of Periodontal Disease in Pets


Stage 1 periodontal disease is the mildest form of the disease. At this stage, the pet's gums may be inflamed and sensitive, and there may be a thin red line on the gum next to the teeth. Plaque may also be visible, but it is still relatively easy to remove.


Calculus, or hardened plaque, may have started to form at this stage, but it is not guaranteed. If calculus has formed, it is important to have it removed by a veterinarian.

Stage 1 periodontal disease is reversible if no calculus has yet formed. This can be done with a thorough cleaning of all accumulated plaque and daily use of a pet dental water additive.

Normal dental radiographs showing bone all the way to the crowns.

Notice where gums lay against the teeth is not perfectly smooth and shows some irregularity.  This is gingivitis and inflammation. 

Action plan for Stage 1:

All dogs and cats with Stage 1 dental disease should have a COHAT to prevent progression to Stage 2.  Daily brushing can sometime prevent this from progressing to stage 2.  See Home Preventative Dental Care recommendations here:  Home Preventative Dental Care


Second Stage of Periodontal Disease in Pets

Stage 2 periodontal disease is more severe than stage 1. The gums are more inflamed and swollen, and there is more plaque and calculus buildup. This can lead to bad breath and loose teeth.

At this stage, the red line on the pet's gum will be wider and more noticeable. This is a big problem because it can cause pain and destabilize the pet's immune system, often leading to infections.

Stage 2 periodontal disease cannot be treated at home.

The good news is that stage 2 periodontal disease is reversible with professional cleaning and diligent home care. Here are some tips for preventing stage 2 periodontal disease:

White arrows are where the bone should be and orange arrows indicate the level of bone loss.

Notice extensive tartar and extremely reddened/inflamed gum tissue.

Action plan for Stage 2:

All dogs and cats at this stage need a COHAT ASAP.  If Stage 2 is not managed immediately then it will progress to bone loss and potentially irreversible damage.  Dental care starts to get very expensive to manage after this stage.  

Third Stage of Periodontal Disease in Pets

Stage 3 periodontal disease is past the point of prevention helping. It is important to avoid this stage at all costs, as it can cause serious damage to the pet's gums and teeth, as well as their overall health.

Unfortunately, many pet owners do not notice periodontal disease until it has reached stage 3. At this stage, the gums are inflamed, swollen, and bleed easily.

Periodontal pockets, which are areas of inflammation between the teeth and gums, have formed. Bone loss is also likely occurring due to the bacterial toxins that are released. Calculus buildup will be significant, and the pet will have bad breath.

Stage 3 periodontal disease can lead to a number of serious health problems, including infections of the kidneys, liver, and heart. However, it is still treatable with professional dental care and diligent home care.

If your pet has stage 3 periodontal disease, schedule a dental cleaning immediately. This stage requires deep cleaning to remove the plaque and calculus, and typically antibiotics and other treatments.

This x-ray shows a tooth root abscess results in bone loss around the entire root. The orange arrows outline the missing bone which has been replace by pus.
Severe tartar, pus along the gemlike and very red/inflamed gums.

Action plan for Stage 3:

All dogs and cats at this stage will need a COHAT and additional, advanced treatments. These treatments will range from tooth extractions, gum surgery, treatments for infections under the gum line. These patients will required regular daily home care daily in addition to the COHAT to keep the dental disease from progressing.

Fourth Stage of Periodontal Disease in Pets

Stage 4 periodontal disease is the most severe and advanced stage of the disease. It is characterized by severe inflammation, gum recession, deep periodontal pockets, bone loss, tooth mobility, and profuse bleeding. At this stage, the damage to the pet's gums and teeth is extensive and irreversible.

Medical treatment is necessary, and sometimes includes tooth extractions. It is important to have your pet evaluated by a veterinarian immediately if they have stage 4 periodontal disease, as it can cause other serious health problems.

Simple cleaning will not be effective at treating stage 4 periodontal disease. Extractions and other dental procedures are likely necessary. Extensive post-surgical care will be required, including frequent and thorough cleanings, medication application, and feeding.

Major bone loss on multiple teeth indicated by orange arrows. These teeth are very loose on exam.
Teeth are almost completely obscured by tartar and pus is evident in many places.

Action plan for Stage 4:

All dogs and cats at this stage will need a COHAT and additional, advanced treatments.  These patients will always needs extractions, gum surgery, and aggressive home care for the remaining teeth.