Endoscopic removal of an ectopic third molar obstructing the osteomeatal complex.

Abstract

We report a rare case of an ectopic third molar at the level of the osteomeatal complex. A 21-year-old man came to us with a left-sided nasal obstruction of 2 years' duration. Computed tomography of the paranasal sinuses revealed that an aberrant tooth was obstructing the osteomeatal complex and bulging into the ethmoid infundibulum. Opacity of the entire left maxillao, sinus indicated the presence of an associated cystic formation. A transnasal endoscopic sinus technique was employed to create a large middle meatal antrostomy and to remove the tooth as well as the cystic contents and cyst wail. Pathologic analysis revealed that the cyst was dentigerous. After recovery from surgery, the patient resumed nasal breathing. The endoscopic surgical approach used in this case caused less morbidity than do the more common methods (e.g., the Caldwell-Luc procedure) of removing ectopic teeth from the sinus.

Introduction

Displacement of maxillary third molars from the normal anatomic location is a result of abnormal development or the presence of a tumor or cyst. In such cases, the teeth can migrate to various locations, including the maxillary sinus, nose, and infraorbital area. (1-3)

In this article, we describe a rare migration of a third molar to the area of the osteomeatal complex. Both the tooth and an associated dentigerous cyst: were removed endoscopically.

Case report

A 21-year-old man came to us with a left-sided nasal obstruction of 2 years' duration. The patient had associated facial fullness, hyposmia, and recurrent headaches--symptoms that suggest a diagnosis of sinusitis. On endoscopic evaluation, a medial bulge of the lateral nasal wall was observed at the level of the left middle turbinate. Computed tomography (CT) of the paranasal sinuses revealed the presence of an aberrant tooth--presumably a third molar--that was obstructing the left osteomeatal complex and bulging into the ethmoid infundibulum (figure 1). In addition, the patient's entire left maxillary sinus demonstrated an opacity on CT that indicated the presence of a cystic formation.

[FIGURE 1 OMITTED]

Access to the tooth, the cystic contents, and the cyst wall was achieved transnasally via an endoscopic sinus approach to create an adequate middle meatal antrostomy. The tooth and its associated cyst adhered closely to the infraorbital wall. They were carefully dissected from their surroundings to avoid injury to the orbital floor.

Dental x-rays, clinical records, and the surgical specimen itself confirmed that the impacted tooth was a third molar (figure 2). Pathologic analysis revealed the nature of the cyst as dentigerous. After recovery from surgery, the patient was able to breathe well through the nose, and all of his other preoperative symptoms, including hyposmia, had resolved. Over a 6-month period of postoperative observation, the patient remained in good health and did not report any symptomatology associated with the third molar irnpaction.

[FIGURE 2 OMITTED]

Discussion

Patients with an ectopic tooth impaction can remain asymptomatic over the course of their lifetime. But when such a tooth migrates, particularly one that is accompanied by a cyst, patients can experience significant morbidity and require intervention. During an endoscopic examination of any patient with suspected chronic sinusitis, the observation of an anatomic disturbance warrants a CT evaluation before any treatment is started. Whenever possible, the surgeon should consider an endoscopic sinus approach rather than more-traumatic techniques such as the Caldwell-Luc method. Followup evaluations to monitor recurrence and the possibility of a malignant transformation of a dentigerous cyst is necessary.

The occurrence of ectopic teeth at sites other than their immediate dental environment is rare. A few reports of tooth displacement in the maxillary sinus, nasal cavity, orbit, chin, mandibular ramus, condyle, and coronoid process have been published. (1-4) The etiology of ectopic teeth is not always known, but it includes developmental abnormalities, overcrowding, trauma, and sepsis. (1,3) Presumably, the etiologic factor is related to the type of tooth (e.g., incisor, canine, third molar, or supernumerary) and its immediate anatomic environment. We report the displacement of a third molar by a dentigerous cyst; such an etiology has been cited in other reports on the ectopic location of third molars in the maxillary antrum or nasal cavity. (1-4) However, the primary difference between these other cases and ours is that our patient experienced an obstruction of the osteomeatal complex, which dictated an alternative surgical approach.

Because of the rarity of tooth impaction in the maxillary sinus, the literature on this subject is limited to case reports. Jude et al reported a case of occlusion of the sinus ostium by an ectopic molar, but its location was lower than it was in our patient, and its removal required an unspecified "anterior antrostomy," probably a Caldwell-Luc approach or a variation thereof. (4) The Caldwell-Luc operation is the standard approach to removing teeth in the sinus. (1,3,5) In our patient, the proximity of the third molar to the medial wall and its height at the level of the osteomeatal complex facilitated endoscopic exploration and extraction. Alexandrakis et al reported a nasolacrimal duct obstruction secondary to ectopic teeth in two patients. (6) The tooth of one of these patients was extracted endoscopically, and the tooth of the other by the Caldwell-Luc approach.

The feasibility of endoscopic removal is related to the ease of endoscopic manipulation, which is enhanced by a close proximity of the tooth to the medial wall of the sinus. For lateral or posterior teeth, the surgeon can use a combined transfacial-transnasal approach, in which a trocar is inserted through the anterior canine fossa; the trocar allows for the introduction of a probe to dislodge the tooth in a medial direction under direct vision. Any related cystic structures can be evacuated at the same time. The dislodged ectopic tooth and associated cyst can then be extracted through a middle meatal antrostomy that is formed during the transnasal endoscopic sinus approach. (7)

Impaction of a tooth in the maxillary sinus can be asymptomatic. (4) Such teeth are often discovered serendipitously on inspection of x-rays of the skull or teeth. In other cases, patients experience significant morbidity, including the symptoms that were experienced by our patient--nasal obstruction, facial fullness, headache, and hyposmia; other symptoms include anosmia, epistaxis, fever, rhinorrhea, and a deviation of the nasomaxillary anatomy. (1,3,4,6) The presence of a cyst that presumably causes the tooth to migrate can be a contributing factor. A large maxillary cyst can involve the entire sinus and transmit pressure to the sinus walls, thereby causing discomfort. Proper diagnosis and treatment require the use of x-rays and CT, as well as an interaction between the head and neck specialist and the dentist.

Dentigerous cysts are the most common type of developmental odontogenic cysts. They form as a result of a separation of the follicle from around the crown of an unerupted tooth, and they attach to the tooth at the junction of the cementum and enamel. Although dentigerous cysts can involve any unerupted tooth, they usually involve third molars; they rarely involve unerupted deciduous teeth. These cysts can also be associated with supernumerary teeth and odontomas. (8)

Dentigerous cysts are encountered over a wide age range, but they are most common among patients between 10 and 30 years of age. Following enucleation of the cyst and extraction of the unerupted tooth, the prognosis is excellent; recurrence is seldom observed after a complete removal. The transformation of a dentigerous cyst to an ameloblastoma is extremely rare, but the possibility should be communicated to the patient. Other rare complications that can arise in the lining of a dentigerous cyst include squamous cell carcinoma and some intraosseous mucoepidermoid carcinomas. (8)

References

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

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

(3.) Pracy JP, Williams HO, Montgomery PQ. Nasal teeth. J Laryngol Otol 1992 ;106: 366-7.

(4.) Jude R, Horowitz J, Loree T. A case report. Ectopic molars that cause osteomeatal complex obstruction. J Am Dent Assoc 1995: 126:1655-7.

(5.) Goodman WS. The Caldwell-Luc procedure. Otolaryngol Clin North Am 1976;9:187-95.

(6.) Alexandrakis G, Hubbell RN, Aitken PA. Nasolacrimal duct obstruction secondary to ectopic teeth. Ophthahnology 2000; 107:189-92.

(7.) Stammberger H. Endoscopy of the maxillary sinus (technique). In: Stammberger H, ed. Functional Endoscopic Sinus Surgery: The Messerklinger Technique. Philadelphia: B.C. Decker, 1991:235-9.

(8.) Waldron CA. Odontogenic cysts and tumors. In: Neville BW, ed. Oral and Maxitlofacial Pathology. Philadelphia: W.B. Saunders, 1995:493-6.

From Trad Hospital and Medical Center (private practice), Beirut, Lebanon (Dr. Hasbini), the Department of Otolaryngology--Head and Neck Surgery, American University of Beirut (Dr. Hadi), and the Department of Orthodontics, School of Dental Medicine. University of Pennsylvania. Philadelphia (Dr. Ghafari).

Reprint requests: Joseph Ghafari, DMD, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, 4001 Spruce St., Philadelphia, PA 19104-6003. Phone: [phone]; fax: [phone]; e-mail: [e-mail]