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Where your pets feel at home

Where your pets feel at home

The Systemic Impacts of Dental Disease

Did you know that dental disease is the most common condition we see in Veterinary Practice?

What causes dental disease? Hint: it’s that furry feeling you get on your teeth if you haven’t brushed them for a day – Plaque! From the moment our pets grow their first set of teeth they start to get plaque building up on the tooth surface. Plaque consists of dead cells, food particles and bacteria (gross!). For us humans, we go and brush our teeth every day and the issue is solved. For our pets though, they can’t brush their teeth as they do not have opposable thumbs and have to rely on chewing things to help get rid of this layer of debris. As you can imagine, this isn’t particularly effective (especially for those pets that don’t like to chew!) and this plaque builds up over time. Eventually, if left to thrive on the teeth, plaque turns to calculus; which is a hard mineralized layer of gross stuff you may notice on your dog or cats teeth if you happened to lift their lip and take a look.


Teeth are held snugly in their places by a few different structures. One of these is the periodontium, which in basic terms is the bone and ligament that hold the teeth in the jaw. The periodontium is covered by a soft squishy protective layer, the gingiva; otherwise known as the gums! I mention this because as our teeth start to develop calculus, these two areas are affected first. These conditions are known as:

Gingivitis – inflammation of the gums, which may show as redness or bleeding. This symptom of dental disease comes first, and is generally reversible.

Periodontitis – the inflammation and infection caused by dental disease has progressed and has now caused bone loss around the tooth or loosening of the ligament holding the tooth in place. This condition is not reversible and will eventually lead to the loss of that tooth. Hence it is important to be proactive and manage our pet’s dental disease at an early stage, before the periodontal ligament is lost. The other important thing to note, is that, periodontitis is often not visible by looking at the gums, but only visible on Xray. Approximately 85% of cats and dogs over the age of 3 years have the start of periodontal disease.

Because of this, at McDowall Vets, we perform complimentary full mouth X rays on all of our patients as part of their dental procedure, so that we can assess the health of the tooth “below the waterline”.

In the Xray above you can see how the premolar teeth have severe periodontitis and have all lost significant bone around their roots, making them unstable and painful. We can also see a tooth root abscess present on the 2nd tooth from the left, which would be causing significant discomfort and requiring that tooth to be extracted.

Other consequences of dental disease may include;
Oral ulcers – may affect the gums, lips or tongue
Caries (aka cavities)
Tooth resorptive lesions – common in cats

What impacts do these conditions have on a systemic level? (How does the dental health affect the rest of the body?)

The oral cavity is a fantastic site for bacteria to grow, encouraging a wide range of bacterial growth, including some particularly nasty bacteria called anaerobic bacteria. In a healthy mouth there are several barriers that stop these bacteria from entering the bloodstream. Unfortunately with gingivitis these barriers break down, and bacteria can easily move into the blood stream (bacteremia). Because the mouth has such a good blood supply, bacteria can easily spread systemically and cause problems around the body. We have known about this for a while – in fact, Hippocrates, the Greek physician, reportedly cured systemic conditions by extracting infected teeth.

Metastatic infection – bacteria that find favourable conditions elsewhere in the body via the blood stream may settle and start to cause infection. Possible sites for infection include the kidneys, heart, brain, lungs, eyes, skin and bones! Infections from the teeth can also arise close to the mouth. We commonly see abscesses in the face caused by dental disease. Ouch!

Metastatic Injury – some bacteria produce toxins, which can be severely poisonous to the body. These are particularly nasty – if you’ve heard of toxic shock syndrome, this is also caused by bacterial toxins. Early research shows these toxins can also cause serious problems including meningitis, stroke and heart attack. These problems are rare – but it’s worth noting!

Metastatic inflammation – bacteria in the bloodstream may cause antibodies to overreact, which can give rise to chronic inflammatory conditions. Examples of these include inflammatory bowel disease and some skin diseases.

There is research suggesting that periodontal disease is capable of predisposing our pets to cardiovascular disease. Oral bacteria can cause your body to make blood clots, which can in turn block arteries. Animals with sore teeth (humans included) will also avoid hard crunchy food (which includes kibble and vegetables!) and opt for high-calorie, high-fat processed food (think dog roll or tinned food) which can in turn predispose them to heart disease.


Dental disease does not cause diabetes – but in diabetic patients, periodontitis can affect glycaemic control. Likewise, diabetic patients are more likely to have dental disease, forming a vicious circle. Studies show that a professional tooth cleaning and a course of antibiotics can greatly improve glycaemic control.

Dental disease can also impact the lungs, and cause pulmonary disease such as pneumonia and bronchitis. This is because the bacteria thriving in the mouth are inhaled into the lower respiratory tract. Generally, the body will fight off this infection – however older patients or patients that have chronic disease may not be able to respond as well.

So what can we do about dental disease and the problems it can cause? As mentioned before, early dental disease (such as gingivitis) is reversible. Ideally, we would be brushing our pets’ teeth twice daily like we do our own! Tooth brushing is something that you have to introduce to your pet slowly, and we can help you do this. Regular chew treats such as greenies (or carrots!) can help also to wear away the layer of plaque on the teeth. Ultimately, regardless of what you do at home, pets need a regular scale and polish just like we get at the dentist.

We hope that you have found this information useful, and it has helped you to realise the importance of maintaining healthy mouths for our pets. It is not “normal” for our pets to have inflamed gums or a smelly breath. Lift up your pet’s lip today and check how they are faring!]

At McDowall Vets we offer free dental checks, where we can discuss this further and help you with developing a good preventative plan for your pet. August is also dental month, where we offer 10% off all dental treatments to help you get your pet back up to date with their dental hygiene. Spots book up fast, so give us a call on (07) 3353 6999. Happy brushing!