If there is an infection – a swelling next to the tooth or pus discharging;
Pain from gums
Pain from ulcers
Mouth ulcers can be a sign of underlying medical conditions such as iron deficiency so shouldn’t be ignored. Any mouth ulcer which doesn’t heal in two weeks should be checked by a dentist.
To reduce the discomfort, you can try a topical ansesthetic gel such as Orajel
To help with healing of ulcers, Gengigel can be effective as well as soothing the pain.
If a tooth or filling has chipped or cracked, this can cause sensitivity from the tooth being exposed or pain to your tongue from sharp edges.
The sensitivity can be reduced by rubbing a de-sensitising toothpaste onto the tooth or placing a temporary filling material over the broken corner until a more definitive filling can be placed.