Dentigerous cysts, or those arising from teeth, are benign, associated with the crowns of permanent teeth, usually involving impacted, unerupted teeth. In 75 percent of all cases, they are located in the mandible, the U-shaped bone forming the lower jaw. The mandibular third molar and maxillary canine are involved most frequently. Dentigerous cysts are the second most common odontogenic cysts after those related to the roots of the teeth. They usually present in the second or third decade of life and are rarely seen in childhood. Dentigerous cysts are usually solitary with multiple cysts reported on occasion in association with syndromes such as mucopolysaccharidosis and basal cell nevus syndrome.
Typically, dentigerous cysts are painless, considered sterile, but may cause facial swelling and delayed tooth eruption. However, head and neck specialists have recently encountered several cases of dentigerous cysts presenting as recurrent head and neck infections or as a deep neck space abscess. A literature review revealed three cases of submasseteric abscess caused by dentigerous cysts and one case of superior orbital fissure syndrome caused by an infected maxillary dentigerous cyst, all reported in the the dental literature.
As this is an ill-defined presentation for these cysts and is underreported, especially in the otolaryngologic literature, otolaryngologists undertook an extensive chart review spanning 30 years in an effort to better delineate this unusual presentation. Their findings are available in the study, Dentigerous Cysts Presenting as Head and Neck Infections authored by Joseph L. Smith, II MD, and Robert M. Kellman, MD, both from the Department of Otolaryngology and Communication Sciences at Upstate Medical University in Syracuse, N.Y. Their findings are to be presented at the 109th annual meeting and OTO EXPO of the American Academy of OtolaryngologyHead and Neck Surgery Foundation, being held Sept. 25-28, 2005 in Los Angeles.
A retrospective chart review from 1975 to 2004 was conducted at a tertiary care center. All charts with an admitting diagnosis of head and neck infection, deep neck space infection (including submasseteric space abscess, retropharyngeal space abscess, and parapharyngeal space abscess) were reviewed. Charts of patients with a diagnosis of dentigerous cyst were reviewed as well. Of the 327 charts reviewed, seven patients were identified who had dentigerous cysts that presented as head and neck infections. From these seven charts, information was obtained. The researchers recorded the patient's age, abscess/infection site, cyst site, presenting white blood cell (WBC) count, culture results, medical and surgical treatment, and length of hospital stay. These results were then compared to previously reported data for these cysts.
Of the 327 charts of patients with head and neck infections reviewed, seven cases were identified in which a dentigerous cyst was the underlying etiology, for an incidence of 2.1 percent. The average age for these patients was 46 years with the range spanning from 29 to 65. The most common infection was located in the buccal space, or adjacent to the cheek. Of these seven cases, six had had previous infections at the same location. The most common cyst site was the ramus of the mandible with the cyst involving an unerupted third molar. All of these cysts were diagnosed by computed tomography (CT) scanning. The average white blood count (WBC) on presentation was 12.0 x 103 with a range of 4.3 x 103 to 23.9 x 103. The most common definitive management of the cysts was enucleation, or removal without structure. For the one case with an extensive abscess associated with it, incision and drainage of the abscess was the first procedure with subsequent enucleation of the cyst once the infection had resolved. All patients were treated with antibiotics prior to surgery. Only one patient required multiple surgical procedures due to recurrence of the cyst. The average length of hospital stay was six days with a range of one to 29 days; the median length of stay was four days. Cultures taken grew H. influenzae, S. pyogenes, and oral flora.
Head and neck infections are not the most common presentation of dentigerous cysts. However, the researchers found that 2.1 percent of head and neck infections serious enough to warrant hospital admission at their institution were due to dentigerous cysts, which is more frequent than expected. Therefore, dentigerous cysts need to be considered as a possible underlying cause when treating head and neck infections. They therefore recommend that unless there is an obvious source of infection, a CT scan should be part of the work up of recurrent head and neck infections as well as those that are serious enough to warrant hospital admission. If a cyst is revealed on radiological imaging, initial treatment is aimed at resolving the infection. Antibiotic coverage should be broad enough to cover typical head and neck infections; coverage can be adjusted as needed based on culture results. Definitive treatment of the cyst should follow resolution of the infection. Since these cysts can reoccur, patients should be followed with annual radiologic studies. For surveillance, panorex or plain films are adequate. Patients with head and neck infections are often referred to otolaryngologist-head and neck surgeons. It is therefore important to be familiar with dentigerous cysts as a possible etiology of these infections.
Source: American Academy of OtolaryngologyHead and Neck Surgery Foundation