Four-Year Follow-Up Of Apical Cyst Of Primary Teeth

Periapical cysts of primary teeth are relatively rare and typically develop secondary to periapical inflammation caused by dental caries or trauma. We reports a case of a 6-year-old child with a periapical cyst affecting the mandibular left first and second primary molars, resulting in ectopic development of the permanent first and second premolar tooth germs, and accompany with anterior crossbite on the right side. After extraction of the affected primary molars, the cyst was treated with decompression. Five months postoperatively, the low-density radiolucent area in the mandibular posterior region had completely resolved, with the formation of a regular trabecular bone structure and vertical repositioning of the premolar tooth germs. A mandibular removable space maintainer followed by a lingual arch was successively used to preserve the space of the prematurely lost primary molars. Occlusal adjustment was performed to gradually eliminate the occlusal interference of the upper right anterior teeth. Four years later, the permanent dentition was fully established and functioned well with individual normal occlusion. Decompression represents superiority as an effective and less invasive treatment in radicular cysts associated with primary teeth. Space management following the premature loss of primary molars must consider the balance between alveolar bone volume and the mesiodistal dimensions of the developing permanent teeth, as well as their stage of development. The case highlights the importance of early diagnosis and treatment of periapical cysts in primary teeth. Proper space maintenance following premature loss of primary molars is essential for guiding the development of occlusion.