The present case report describes the case of a 15-year-old female who was referred with a radiolucent lesion between her mandibular right molars. The original radiographic image suggested the presence of an odontogenic cyst. The surgical enucleation and the following osteotomy of the residual cavity was performed by using the piezoelectric technology. The histological analysis confirmed that the lesion was an odontogenic keratocyst with no evidence of epithelial invasion in the connective tissue wall. The patient refused any further surgical treatment. In consideration of the pathological result - no presence of invasive epithelial cells in the connective tissue wall of the cyst- the patient was suggested a "follow-up and wait-and-see policy", with more extensive surgical treatment to be given only in case of a recurrence. The patient was followed up clinically and radiographically at 6 months intervals for 5 years.