Teeth with double internal inflammatory resorption: report of two cases.

Internal inflammatory resorption is an uncommon condition, which requires the presence of necrotic and infected pulp tissue within the coronal portion of the root canal system as well as inflamed pulp tissue apical to the resorptive defect. The defect usually appears as a bowl-shaped radiolucency within the tooth root. Most cases are asymptomatic and many cases are only seen once the entire pulp has necrosed and all of the root canal system is infected resulting in apical periodontitis. The two cases presented are unusual in that they both had two distinct areas of internal inflammatory resorption. It is hypothesised that the more coronal lesion occurred first and then it ceased to continue resorbing the root in that position as the 'necrotic, infected front' moved apically at which time a second resorptive defect developed. The management, using different approaches, of these two cases of 'double internal inflammatory resorption' is described.