Pain on Apical Palpation as an Indicator for Acute Apical Abscess

Objectives: The emergency treatments of acute apical abscess (AAA) and acute apical periodontitis are different. It is thus important to have a good differential diagnosis. This study aimed to evaluate the validity of pain on palpation of the periapical area as an indicator of acute apical abscess without swelling. Methods: The study material was 53 Patients with pulp necrosis and spontaneous pain exacerbated by percussion. The intensity of spontaneous pain, pain on percussion, pain on apical palpation, and tooth mobility were registered. Drainage was attempted firstly by opening the pulp chamber, secondly by transfixing the apical constriction and it was noted if purulent exudate occurred. The gold standard for assessment of the diagnosis of AAA was the presence of purulent exudate. Results: there was no evidence of relation (p>0.05) between intensity of spontaneous or percussion pain, degree of tooth mobility and presence or absence of purulent exudate after draining via the root canal. Conversely, a statistically highly significant (p<0.001) relation was found between tenderness on apical palpation and the presence of purulent exudate. This test had 96.2% sensitivity (95% C.I. 0.80, 1.00), 70.4% specificity (95% C.I. 0.51, 0.85) and its positive and negative predictive values were respectively 75.8% and 95.0%. Conclusion: Painful apical palpation was considered a strong diagnostic indicator for acute apical abscess.