Severe, localized pain in back teeth combined with painful white gum sores strongly suggests an inflammatory process. This could be pericoronitis (gum infection, often associated with a partially impacted wisdom tooth), a painful tooth ulcer (canker sore), an localized gum abscess from trapped food, or advanced decay (cavities) with pulpal involvement.
Next Steps
Schedule an appointment with a dentist as soon as possible, ideally today or tomorrow. These symptoms require a visual examination and likely a dental X-ray to diagnose the exact cause.
Health Tips
A crucial warning sign to look out for is any significant facial or neck swelling, fever, or difficulty swallowing or breathing, which could indicate a severe, spreading infection and necessitates an immediate visit to the nearest emergency room. While over-the-counter pain relievers can provide temporary comfort, they only mask symptoms and will not treat the underlying cause. Please do not apply any topical over-the-counter ulcer medications until a dentist has confirmed the diagnosis, as some can irritate the pulp if the cause is a deep cavity.