Clinical Manifestations
Clinical Manifestations
The cardinal symptom of acute apical periodontitis is percussion sensitivity — pain produced by tapping the tooth vertically (along its long axis) with a mirror handle. In early stages this may be mild; in fully developed abscess it is exquisite, with patients describing the tooth as feeling 'high,' 'elongated,' or different from adjacent teeth due to periodontal ligament edema causing slight tooth displacement.
Patients typically present with a recent history of throbbing toothache or a sudden onset of severe pain in a previously asymptomatic (necrotic) tooth. Unlike pulpitis pain, apical periodontitis pain is well-localized: the patient can precisely identify the offending tooth because the periodontal mechanoreceptors — unlike pulpal pain pathways — provide accurate topographic information.
In acute apical abscess, soft tissue swelling develops as pus dissects through bone. The swelling location depends on the relative position of the root apex to muscle attachments and fascial spaces: a maxillary incisor abscess swells the upper lip; a maxillary molar apex above the buccinator insertion swells the cheek; a mandibular molar below mylohyoid causes submandibular space involvement.
Systemic signs — fever >38°C, trismus (inability to open mouth > 30mm due to masseteric or pterygoid muscle involvement), dysphagia, lymphadenopathy — indicate spreading infection requiring urgent surgical drainage and hospitalization consideration. Ludwig's angina (bilateral submandibular-sublingual-submental space involvement) is a life-threatening emergency.