KnowledgeDental Health Articles &
Dental Health Articles &
Oral Care Guides
Evidence-based answers to the dental questions patients actually ask. Every article written and medically reviewed by Dr Cristian Dunker and the ArtSmiles clinical team.
Mouth Ulcers & Sores
Erythema Multiforme: when sudden mouth ulcers and crusted lips appear together
Erythema multiforme is a sudden immune reaction causing mouth ulcers, crusted lips, and target lesions on the skin. Reviewed by Dr Cristian Dunker.
9 May 2026
Mouth Ulcers & Sores
Traumatic Ulcer: when a sore in your mouth doesn't heal
Traumatic ulcers are the most common cause of a single mouth sore. Learn what causes them, how they heal, and the two-week rule. Reviewed by Dr Cristian Dunker.
9 May 2026
Mouth Ulcers & Sores
Recurrent Aphthous Stomatitis: when canker sores keep coming back
Recurrent aphthous stomatitis — better known as canker sores — is very common. Here's how it looks, what triggers it, and when to seek care. Reviewed by Dr Cristian Dunker.
9 May 2026