 b. Periapical i. Symptomatic apical periodontitis with or without a radiographic apical lesion ii. Asymptomatic apical periodontitis with a radiographic apical lesion iii. Acute apical abscess iv. Chronic apical abscess Teeth will be deemed non-vital if either are non-responsive to sensibility tests i.e. Electric Pulp test and cold tests, andor present with signs and symptoms of non-vitality e.g. swelling and abscess. 