Pathogenesis
Bacterial colonization under the operculum produces toxins and enzymes (collagenase, hyaluronidase) that break down connective tissue and promote local inflammation.
The anaerobic gram-negative organisms release lipopolysaccharides (LPS) that trigger a strong innate immune response, causing tissue edema, exudate formation, and pain.
If not resolved, infection tracks along fascial planes: from the third molar region into the pterygomandibular, masseteric, parapharyngeal, and submandibular spaces — potentially threatening the airway.
Trismus (limited mouth opening) occurs when infection involves the masseteric or pterygomandibular spaces, causing muscle spasm and inflammatory edema around muscles of mastication.