What really keeps your mouth and gums healthy?

Dental plaque, the bacterial film that forms on your teeth every day, is the main cause of gum inflammation and gum disease. That is robustly established. Brushing daily to remove that plaque mechanically is therefore the absolute foundation of good oral health.

Toothbrushing alone does not reach the spaces between teeth. Interdental brushes (small brushes designed to clean between teeth) appear to be the most effective tool for that purpose: they reduce both plaque and gum inflammation more than flossing does. Flossing helps too, but the difference compared with brushing alone is small and the evidence is of low certainty. Water flossers are disappointing: a small effect on gum inflammation seen after one month disappeared thereafter, and no benefit over brushing alone was found for plaque. The practical conclusion: interdental brushes are your best supplement to the toothbrush, flossing is an acceptable alternative, and a water flosser is no substitute for mechanical cleaning.

If you have type 2 diabetes, gum care is especially important. Poor blood sugar control increases the risk of serious gum disease, and conversely a significant gum infection can make your blood sugar harder to manage. Getting treatment pays off: professional cleaning by the dentist lowered average blood sugar levels (HbA1c) by an average of 0.43 percentage points after three to four months. That is a clinically meaningful effect, comparable to what some medication adjustments achieve. Yet far from everyone with diabetes knows this interaction exists; if your doctor or diabetes nurse does not bring it up, it is worth raising the subject yourself.

In elderly residents of nursing homes, oral health is often alarmingly poor: more than half have tartar, around 30% have moderate to severe gum disease and up to 40% have problems with a denture. This is linked to cognitive decline and reduced ability to care for oneself, and in turn affects nutrition and quality of life. Active support from carers and dental professionals is indispensable here.

Finally, mastic gum, a resin that is sometimes promoted as an oral health supplement, showed antibacterial effects in laboratory and small clinical studies. However, there are very few studies in humans, and the results are not yet reliable enough to act on. It has not been proven to work.