Pathogenesis
Pocket orifice occlusion → anaerobic bacteria multiply in closed-space environment → leukotoxin (from Aggregatibacter actinomycetemcomitans) and gingipains → massive neutrophil recruitment → liquefactive necrosis → pus formation (dead neutrophils + bacteria + tissue debris).
Pus under pressure: if it tracks coronally through the pocket → spontaneous drainage. If blocked → pressure builds → periosteal perforation → fistula through mucosa → parulis (gumboil). Fascial space spread: buccal, pterygomandibular (trismus), submandibular, sublingual. Bilateral submandibular-sublingual-submental spread = Ludwig's angina.