High blood sugar causes increased salivation, makes your mouth dry and increases the risk of inflammation. A clean mouth is less affected by the effects of high blood sugar. A fungal or bacterial infection may cause sensitivity in the mucous membranes. For someone with diabetes, a bacterial infection is often caused by a mouth bacterium that is harmless to a healthy individual. Sores and cuts inside the mouth also take longer to heal, if the blood sugar is high.
If you have diabetes, it's especially important to remove bacterial plaque from your teeth by brushing thoroughly in the mornings and evenings, and by cleaning between your teeth daily. If necessary, you may also need to increase the frequency of brushing.
Good blood sugar balance is also beneficial for oral health. High blood sugar also affects the mouth. It can result in more tooth decay and oral infections. Repeatedly correcting low blood sugar can also increase the sugar level in the mouth.