A panoramic radiograph shows a very deep restoration adjacent to the apex of a tooth. What is the most likely diagnosis for the radiopaque area seen at the root apex?

Condensing osteitis (focal sclerosing osteomyelitis) is a variant of chronic apical periodontitis that presents as a localized, radiopaque area of increased bone density at the root apex. It occurs as a reactive response to low-grade, chronic inflammation — most commonly caused by a deep restoration or caries causing pulpal irritation. Unlike cementoblastoma, it is not attached to the root, and unlike idiopathic osteosclerosis, it has a clear dental etiology. On a panoramic radiograph, it appears as a well-defined radiopaque area surrounding the offending root. Treatment is directed at the pulp (root canal therapy) if symptoms or pulpal testing indicate it is necessary.