Clinicopathological study of periapical scars

Background/purpose: Periapical scar (PS) is an alternative healing process with the formation of scar tissue after appropriate endodontic treatments/retreatments with or without periapical surgeries. This retrospective study evaluated the clinical, radiographic, and histopathological features of 7 PSs. Materials and methods: The clinical, radiographic, and histopathological data of 7 PSs were collected and analyzed. Results: The 7 PSs were taken from the maxilla (3 cases) and mandible (4 cases) of 3 men and 4 women. The most frequently involved teeth were maxillary or mandibular incisors (4 cases) and first or second molars (3 cases). Of 7 PS patients, 6 had none of symptoms, 5 had previous nonsurgical endodontic treatments/retreatments, and 2 had previous endodontic treatments/retreatments plus periapical surgery. Radiographically, all 7 PS cases presented as a persistent and well-defined periapical radiolucent lesion for a long period of time. Microscopically, all 7 surgical specimens of PS showed dense fibrous collagenous tissues with one having amalgam particles in the scar tissue. Conclusion: PSs do have their common clinical and radiographic features. When the periapical radiolucent lesion is well-defined, persistent without a significant change of its size, and free from symptoms and signs after a long-term follow-up; the involved tooth has no evidence of root fracture and healthy periodontium except the periapical radiolucency; and the previous endodontic treatment/retreatment or periapical surgery is well performed with an adequate root canal or retrograde filling, then the PS may be a possible diagnosis and a close follow-up may be a more conservative treatment strategy for this condition.