Clinical Manifestations
ACUTE: Severe, throbbing, well-localised pain. Smooth, ovoid, fluctuant gingival swelling. Erythematous overlying mucosa. Tooth extrusion (patient bites on it first). Percussion tenderness.
SYSTEMIC SIGNS: Low-grade fever (37.5–38.5°C); malaise; regional lymphadenopathy. Trismus (<20mm opening) indicates fascial space spread — URGENT.
CRITICAL DIFFERENTIATOR — Periodontal vs Periapical: Periodontal abscess: tooth VITAL (positive EPT and cold test); deep pocket on probing communicates with abscess; history of periodontitis. Periapical abscess: tooth NON-VITAL (negative tests); periapical radiolucency on X-ray; no deep pocket history at that tooth.