Introduction
Odontogenic cysts are among the most frequent pathological entities in the maxillofacial region. They are typically classified as developmental or inflammatory, with common variants including periapical, dentigerous, and periodontal cysts. Among periodontal cysts, the lateral periodontal cyst (LPC) is a relatively uncommon lesion, accounting for about 0.4% of odontogenic cysts in adults over three decades of data. Diagnosing LPC can be challenging because clinical and radiographic features often overlap with other cystic entities. Accurate differential diagnosis is essential, as treatment decisions and prognosis hinge on the underlying pathology.
Case overview
The present report describes a 35-year-old male with a progressive gingival swelling in the maxillary anterior region. Clinically, a palpable, firm, non-fluctuant swelling extended buccally between teeth #22 and #23. Pockets of 14 mm and 15 mm were detected mesially and distally around the affected teeth, with pocket exudate suggesting a cystic process. Vital teeth and lack of periapical radiolucency pointed toward a LPC-like presentation. CBCT showed a low-density radiolucent area between the roots with partial buccal cortical loss, but no root resorption or extensive bone destruction.
Initial management and diagnostic challenge
The provisional diagnosis favored LPC based on clinical and radiographic findings. The treatment plan included SRP followed by surgical excision of the cyst with guided tissue regeneration (GTR). After scaling and root planing, the cyst appeared to reduce in size, and the patient opted against immediate surgery. A six-month follow-up revealed rapid cyst enlargement with buccal cortical plate separation, underscoring the transient nature of inflammatory relief versus true cyst diminution and prompting reassessment of the diagnosis and management plan.
Surgical management and histopathology
Under local anesthesia, an intrasulcular incision and mucoperiosteal flap exposed a cyst occupying the alveolar bone. The cyst was enucleated in toto, and the buccal cortical plate was found to be severely thinned and pliable, indicating significant bone compromise. The osseous defect was grafted with deproteinized bovine bone mineral (Bio-Oss) and covered with a collagen barrier (Bio-Gide). The excised tissue was submitted for histopathology.
Microscopy revealed a cyst lined by non-keratinized squamous epithelium with scattered ghost cells and calcifications, consistent with a calcifying odontogenic cyst (COC). This finding contrasted with the clinical presumption of LPC and highlighted the critical role of histopathology in delivering a definitive diagnosis.
Follow-up and outcomes
The patient’s postoperative course was uneventful, with complete mucosal epithelialization within two weeks. Periodontal maintenance therapy was provided every three months. At the 12-month follow-up, there was excellent bone regeneration, no lesion recurrence, and preserved periodontal health, indicating a favorable outcome after conservative management with enucleation and GTR.
Discussion: LPC vs COC in periodontal tissues
LPC and COC are distinct entities with different biological behaviors. LPCs are usually benign, asymptomatic lesions that occur between vital teeth and are commonly managed with conservative enucleation. COCs can present as cystic or solid lesions and may display calcifications (ghost cells) on histology. Radiographically, COCs often show mixed radiolucent-radiopaque features due to intracystic calcifications, whereas LPCs typically appear purely radiolucent. The case underscores the diagnostic pitfall: a lesion within periodontal tissues might be misinterpreted as LPC when radiographs and clinical features are ambiguous. Histopathology remains the gold standard for differentiating COC from LPC and guiding appropriate management.
Clinical implications and lessons learned
This case supports a conservative approach for non-aggressive COC variants if imaging suggests confinement and histology confirms a simple cystic pattern. Key considerations include meticulous CBCT assessment, intraoperative evaluation for aggressive features, and a cautious balance between complete lesion removal and preservation of surrounding bone. Long-term surveillance remains essential given the potential—but relatively low—recurrence risk with non-aggressive COC. Multi-disciplinary collaboration integrating clinical, radiographic, and histopathological data is vital in ambiguous odontogenic lesions.
Conclusions
In this rare periodontal-located COC case, initial misdiagnosis as LPC was resolved by histopathology. CBCT imaging guided treatment planning, and conservative enucleation with GTR achieved favorable healing at one year. The report emphasizes the importance of considering COC in the differential diagnosis of periodontal cysts and advocates for tissue-preserving strategies in carefully selected cases, pending longer-term evidence.
