There are a number of reasons why gum recession could present itself, including:

• Overzealous tooth brushing with hard toothbrush bristles.
• An inherited predisposition for thin gum tissue.
• Malpositioned teeth, which leads to the spreading or crowding of teeth.
• Clenching and grinding of teeth, which some dentists believe causes recession.
• Nervous habits like inserting foreign objects in the mouth or scratching the gums with foreign objects.