My gums are swollen and hurt on one side
One-sided painful gum swelling may come from trapped plaque, a gum pocket, an erupting tooth, trauma, or an infection near a tooth.
The short answer
Localised gum swelling is inflammation or enlargement of the gingiva beside a particular tooth or area, rather than a diagnosis by itself.

What is the direct answer?
What does this question mean?
Common causes include plaque-related gingivitis, food trapped under the gum, a periodontal pocket, an erupting wisdom tooth, a sharp filling edge, or an abscess from the tooth pulp. The dentist checks the gum, tooth vitality, pocket depth, and imaging when needed.
What can you do next?
Rinse gently with warm water, brush softly with fluoride toothpaste, clean between the teeth if it does not cause sharp pain, and avoid squeezing the swelling. Do not place caustic substances on the gum; arrange an examination to remove the cause.
When should you seek dental care?
Seek urgent dental care for spreading facial swelling, fever, pus, difficulty opening the mouth, swallowing, or breathing. A persistent lump, bleeding area, or swelling that returns also needs examination.
What should you ask the dentist?
Ask whether the swelling is in the gum or from the tooth, whether a pocket or abscess is present, and whether cleaning, drainage, a filling, root canal treatment, or another procedure is needed.
Frequently asked questions
Can home care fix the underlying problem?
Home care may reduce irritation or pain temporarily, but it cannot diagnose or remove the dental cause. Arrange an examination when symptoms persist or return.
What will the dentist check first?
The dentist reviews the symptom pattern, examines the teeth and soft tissues, and uses targeted tests or imaging when those findings are needed to identify the cause.
