A metallic taste, breath that smells faintly of ammonia, and a mouth that always feels dry are often put down to poor brushing. In people with chronic kidney disease they can be a direct effect of the condition. Gum disease also appears to be more common in people with reduced kidney function, and researchers think each condition may make the other harder to control.
None of this means kidney disease will damage your teeth. It does mean your mouth needs a little more attention, and that your dentist should know about your kidneys.
Inflammation is the common thread
Gum disease is a long-running bacterial infection of the tissues that hold the teeth. Where gums are inflamed and bleeding, bacteria and inflammatory signals can pass into the bloodstream. Chronic kidney disease is itself associated with ongoing, low-grade inflammation through the body, so an infected mouth adds to a load that is already raised.
Systematic reviews have found periodontitis to be more common in people with chronic kidney disease than in people without it, although the certainty of that evidence is rated as low. Some studies also suggest that people with both conditions may have poorer kidney and heart outcomes. These are associations, and the studies cannot prove that gum disease causes kidney decline. Treating gum disease is still worthwhile for its own sake, and it removes one source of inflammation you can actually do something about.
Many of the same risk factors sit behind both
Diabetes and high blood pressure are among the main causes of chronic kidney disease in Australia, and diabetes is also one of the strongest risk factors for gum disease. Smoking harms both the gums and the blood vessels of the kidneys. So the two conditions often arrive together for reasons that have little to do with each other directly. The same pattern appears in our articles on diabetes and gum disease and rheumatoid arthritis and gum disease.
Changes you may notice in your mouth
A dry mouth
Dry mouth is common in kidney disease. Fluid limits, several commonly used medicines and the condition itself all reduce saliva. Saliva rinses away food, buffers acid and carries minerals that repair early decay, so a dry mouth raises the chance of cavities, especially around the gumline and old fillings. Our guide to dry mouth has more on relief.
Metallic taste and ammonia breath
When the kidneys clear less urea from the blood, more of it appears in saliva, where bacteria break it down into ammonia. The result can be a bitter or metallic taste and a characteristic breath odour. It tends to be worse before dialysis and ease after it. Brushing and tongue cleaning help a little, but this is a chemical effect, not a sign of neglect.
Gums that bleed or swell
Bleeding when you brush is the earliest sign of gum inflammation, covered in our article on bleeding gums when brushing. In kidney disease, some blood pressure medicines and some anti-rejection medicines used after a transplant can also cause the gums to thicken and grow over the teeth, which makes cleaning harder. Tell your dentist or OHT if your gums look bulkier than they used to.
Changes in the jawbone
Kidney disease affects how the body balances calcium, phosphate and parathyroid hormone. Over time this can change the density of bone, including the jaw. It rarely causes symptoms in the mouth, but it can show on dental X-rays and is one reason your dentist will want your medical history.
Daily care that fits around fluid limits
Brushing twice a day with a fluoride toothpaste and cleaning between the teeth once a day remain the most useful habits. For dry mouth, small sips of water within the fluid allowance your kidney team has set, sugar-free gum, and saliva substitute gels or sprays can help. Avoid sucking boiled lollies or sipping sweet drinks to keep the mouth moist, since that feeds decay. Your dentist may suggest a higher-strength fluoride toothpaste if dryness is persistent. If you smoke, stopping helps your gums and your kidneys at the same time.
What your dentist needs to know
Routine dental care is generally safe for people with kidney disease, but it goes more smoothly with some planning. Bring an up-to-date medicine list and the contact details of your renal team. Useful things for us to know include:
- your current stage of kidney disease or most recent kidney function result
- if you have dialysis, what type and on which days
- any blood thinning given with dialysis, since treatment is usually booked for a non-dialysis day
- any transplant, past or planned
Many medicines are cleared by the kidneys, so doses of some antibiotics and pain relievers may need adjusting, and anti-inflammatory pain relievers are generally avoided. If you are being assessed for a kidney transplant, your renal team will usually ask for a dental check to clear any infection beforehand. If missing teeth are part of the picture, our article on dental implants with kidney disease or dialysis looks at that question.
Keeping on top of it costs less than catching up
For most people with kidney disease, staying ahead of gum problems comes down to regular examinations and professional cleans rather than larger treatment. As a typical Australian market range, not a Lumi fee, a check-up and clean commonly costs $200 to $400. Health fund extras cover often contributes, which our article on what dental cover includes explains.
Questions we are often asked
Can treating my gums help my kidneys?
Some small studies have reported improvements in inflammatory markers after gum treatment in people with kidney disease, but the evidence is limited. Gum treatment should be seen as part of looking after your general health, not as a treatment for the kidneys.
Is it safe to have dental work on a dialysis day?
Usually the day after dialysis is preferred, when fluid and chemical balance are at their best and any blood thinning given during dialysis has worn off. Your dentist can check with your renal team if unsure.
Why does my mouth taste worse before dialysis?
Urea builds up between sessions and passes into saliva, where it breaks down into ammonia. The taste and breath usually improve once dialysis has cleared some of it.
Our dentists and oral health therapists at Lumi Dental in Melrose Park can check your gums, help manage dry mouth and liaise with your kidney team where needed. To arrange a visit, see our current offers or book a general dental check.
This article is general information and not a substitute for personal advice from your dentist and kidney care team.
