Mouth crease sore
A sore at the corner of the mouth may come from moisture and saliva, irritation, contact dermatitis, infection, a denture, or a local dental problem.
The short answer
The corner is the oral commissure. Repeated wetting, lip licking, reduced bite height, yeast, and bacteria can cause cracking, crusting, burning, and tenderness.
What is the direct answer?
What does this question mean?
Keep it gently clean and dry, avoid licking or picking, and pause products that sting. A clinician can inspect the skin, teeth, oral lining, and denture fit before choosing treatment.
What can you do next?
Seek care if it lasts, recurs, spreads, bleeds, or has pus or marked swelling. Urgent care is needed for fever or trouble swallowing.
When should you seek dental care?
Ask whether it is angular cheilitis, contact irritation, or another lesion, and whether a denture or bite issue contributes.
Frequently asked questions
Can home care replace an examination?
Home care supports hygiene but cannot diagnose or treat problems such as calculus, decay, or an abscess.
What if symptoms worsen?
Arrange prompt dental care for worsening pain, swelling, drainage, or persistent bleeding.