Inflammatory dentigerous cyst of mandibular first premolar associated with endodontically treated primary first molar: a rare case report.

AIM: Inflammatory dentigerous cysts usually occur in the mixed dentition. It has been reported that inflammatory lesions from the root area of a deciduous tooth bring about the development of dentigerous cysts around the unerupted permanent tooth bud. Endodontic treatment is a common and successful procedure for periapical inflammation in children. An inflammatory dentigerous cyst can occur in conjunction with endodontically treated primary tooth. CASE REPORT: This article reports a case of 6 years and 6 months old boy, with a single, well-defined, unilocular, radiolucent area enclosing the first right unerupted mandibular premolar, accidentally discovered on the panoramic radiograph. The first right primary molar had received a root canal treatment 18 months prior. Clinical findings combined with radiographic and microscopic examinations confirmed the diagnosis of inflammatory dentigerous cyst. As treatment, enucleation of the cyst with removal of the involved permanent tooth was chosen and a removable partial denture was supplied to the patient after surgery. The 5-year follow-up revealed good healing of the bony lesion and displaced teeth. CONCLUSION: This case presented a severe and rare complication of endodontically treated primary tooth, and the recommendation includes: (1) early diagnosis of dentigerous cysts, which is essential to prevent extensive treatment; (2) more information on the adverse side effects of an endodontic treatment should be given to patients and parents; (3) patients should be informed about the importance of follow-ups and radiographic follow-up should be routinised.