K13: Other diseases of lip and oral mucosa

The group of conditions classified under the title "Other diseases of lip and oral mucosa" generally pertain to disorders that affect the lips and lining of the mouth. These conditions often result from factors like viral or bacterial infections, autoimmune diseases, nutritional deficiencies, irritants like tobacco, alcohol, and certain medications, or poor oral hygiene. Common symptoms can include mouth sores or ulcers, a burning or painful sensation in the mouth, discolorations or patches on the lips or inside the mouth, swelling or thickening of areas in the mouth, or persistent discomfort in the mouth or lips. These conditions can progress and potentially affect oral functions such as speaking, eating, and swallowing, and lead to complications if not addressed. As these diseases all involve the oral mucosa, they primarily affect the body's digestive system.