Endoscopic removal of a dentigerous cyst producing unilateral maxillary sinus opacification on computed tomography.

Abstract

We report the case of a 14-year-old girl who was referred to us with a 2-year history of abnormal panoramic dental x-rays. Computed tomography of the paranasal sinuses demonstrated a left unilateral maxillary sinus opacification that had been produced by an ectopic molar: The tooth was removed via an endoscopic approach rather than with a traditional Caldwell-Luc procedure. A nasal endoscope was used to create a middle meatal antrostomv and deliver the tooth and its cystic contents. The patient recovered without complications, and she exhibited no signs of recurrence at the 2-year follow-up.

Introduction

Although ectopic and supernumerary teeth are rare, they have been reported in a variety of sites, including the orbit, palate, nasal cavity, maxillary sinus roof, and chin. (1-3) These teeth are believed to have migrated as a result of developmental aberrations. It has also been suggested that ectopic teeth may develop as a result of trauma, genetic factors, and infections. (2) In this article, we present one of the few reported cases in which endoscopy was used to remove an ectopic third molar. (4)

Case report

A 14-year-old girl was referred to us for evaluation of a displaced third molar. Her dentist had monitored her for 2 years with the aid of serial panoramic x-rays. These x-rays revealed that the molar appeared to be migrating into the maxillary sinus.

The patient denied headaches, facial pain, and facial pressure, and she had no history of sinus infection. The results of an endoscopic evaluation were unremarkable. However, findings on computed tomography (CT) were compatible with a dentigerous cyst in the left maxillary sinus (figure 1). In addition, the patient's entire left maxillary sinus was opacified as a result of the cyst's obstructing the osteomeatal complex.

[FIGURE 1 OMITTED]

Endoscopic sinus surgery was performed to remove the tooth and cyst. A middle meatal antrostomy was created transnasally with a 30[degrees] rod endoscope and a minishaver. Meticulous surgical technique was used to avoid complications involving injury to the eye and the nasal lacrimal duct. The tooth and associated cyst were delivered in one piece with a 120[degrees] antral grasping forceps (figure 2). Pathologic review of the specimen confirmed our diagnosis. The patient recovered uneventfully, and she remained free of recurrence at the 2-year follow-up.

[FIGURE 2 OMITTED]

Discussion

Dentigerous cysts are the most common type of developmental odontogenic cyst. They can involve any developing tooth, but most affect the third molar; deciduous teeth are not often involved. A dentigerous cyst develops when a follicle is separated from the crown of a developing tooth. The cyst is bound to the tooth at the abutment of the enamel and cementum. (5)

Most dentigerous cysts occur in patients aged 10 to 30 years, and many go unnoticed throughout a patient's entire life. In such cases, dentigerous cysts in the maxillary sinus may be discovered incidentally on x-rays of the skull or teeth. In other instances, patients become symptomatic and experience the classic signs of sinus disease. (6)

When a cyst causes symptoms or disease that is not improved by medical therapy, surgery becomes necessary. Although the traditional Caldwell-Luc procedure provides a direct view into the maxillary sinus, it is associated with more morbidity than is transnasal endoscopy. Patients with a dentigerous cyst require periodic monitoring to identify and manage a malignant transformation or, in the case of cyst removal, a recurrence. The literature contains a few rare reports of dentigerous cysts that changed into a squamous cell carcinoma, a mucoepidermoid carcinoma, and an ameloblastoma. (5) Most cysts do not return after complete surgical removal.

Approximately 50 cases of a tooth in the nasal cavity have been reported in the literature. (7) In a case report published in 2001, Hasbini et al wrote that the proximity of the third molar to the medial wall of the maxillary sinus and its height at the level of the osteomeatal complex facilitated endoscopic exploration and extraction. (4) The anatomic location of a maxillary dentigerous cyst and the level of an individual surgeon's ability will determine whether a patient can be operated on endoscopically. Cysts that are close to the osteomeatal complex can be removed endoscopically, but cysts that lie laterally or posteriorly are more easily removed under the direct vision that a Caldwell-Luc approach provides. If a cyst and tooth are too large to be delivered through the anterior superior canine opening, the surgeon can use a combined Caldwell-Luc and endoscopic approach. The freed tooth and cyst can be removed through an appropriately sized middle meatal antrostomy.

Our case was interesting for three reasons:

* Ectopic eruption of a tooth into an area other than the dental area is rare.

* The cyst obstructed the osteomeatal complex and produced maxillary sinus opacification on CT.

* This is one of the few reported cases in which the patient was treated endoscopically.

References

(1.) Martinson FD, Cockshott WP. Ectopic nasal dentition. Clin Radiol 1972:23:451-4.

(2.) Elango S, Palaniappan SP. Ectopic tooth in the roof of the maxillary sinus. Ear Nose Throat J 1991;70:365-6.

(3.) Gadalla GH. Mandibular incisor and canine ectopia. A case of two teeth erupted in the chin. Br Dent J 1987;163:236.

(4.) Hasbini AS, Hadi U, Ghafari J. Endoscopic removal of an ectopic third molar obstructing the osteomeatal complex. Ear Nose Throat J 2001:80:667-70.

(5.) Waldron CA. Odontogenic cysts and tumors. In: Neville BW, Datum DD, Allen CM, Bouquot JE, eds. Oral and Maxillofacial Pathology. Philadelphia: W.B. Saunders; 1995:493-6.

(6.) Bodner L, Tovi F, Bar-Ziv J. Teeth in the maxillary sinus--imaging and management. J Laryngol Otol 1997;111:820-4.

(7.) Gupta YK, Shah N. Intranasal tooth as a complication of cleft lip and alveolus in a four year old child: Case report and literature review. Int J Paediatr Dent 2001:11:221-4.

Paul Di Pasquale, DO; Carl Shermetaro, DO

From the Department of Otolaryngology, POH Medical Center, Pontiac, Mich.

Reprint requests: Carl Shermetaro, DO, 6770 Dixie Hwy., Suite 302, Clarkston, MI 48346. Phone:[phone]; fax:[phone]; e-mail: [e-mail]