A Misdiagnosed Dental Lesion

Dr. Ken Goldstein

Endodontists are accustomed to treating periradicular infections with accompanying sinus tracts. Most sinus tracts occur on the buccal or lingual aspect of a tooth or in some cases, teeth. Although rare, sinus tracts can also occur on the outer cheek or chin called an odontogenic cutaneous sinus tract. According to Barrowman RA, et al,¹ these sinus tracts can resemble a pimple, ulcer, nodule, or indurated cystic area.

Therefore, this particular sinus tract can be misdiagnosed because they may appear as a dermatologic issue at first glance. Patients end up seeing their primary care physician or dermatologist for treatments that usually are not successful. According to Cantatore et al,² half of the patients with odontogenic cutaneous sinus tracts undergo multiple dermatological procedures before a correct diagnosis is made. Unfortunately, this delay in treatment can cause an increase in the “chronicity” of the apical lesion which can “dissect” through the path of least resistance and erupt onto the skin. Winstock ³ found in his study that diagnosis of these sinus tracts can be difficult because the tracts do not always occur near the infected tooth and half of the patients do not report any tooth pain. This is because an apical lesion with an accompanying sinus tract is usually not painful due to the sinus tract acting as a vehicle for the release of exudate which can decrease the pain.4 Therefore, patients may call their primary care physician or dermatologist before they call the dentist because they have no pain and most patients associate pain with a dental issue and not so much a dermatologic issue.

By diagnostic testing of the teeth in the area of the cutaneous sinus tract and by taking radiographs to verify the presence of an apical lesion, the dentist could save his or her patient from receiving multiple surgical excisions, biopsy samples and rounds of antibiotic therapies which will be ineffective and not necessary and may result in the sinus tract reoccurring on the face or neck.5 This is exactly what happened in the case that is being presented.

Case Scenario:

A 78 year old female in good health developed a small crust like skin lesion on her left cheek and was seen by her dermatologist who drained the lesion. Nevertheless, the patient noticed the area was not healing even after several treatments. After five months and no healing, the dermatologist referred the patient to our office to evaluate tooth # 13 which I originally treated to see if the lesion on her cheek could be related to the tooth. Clinical and radiographic examination of tooth # 13 showed healing of the apical lesionand tooth # 13 was asymptomatic. Next, a radiograph was taken of teeth #’s 11 and 12 and a periapical lesion was discovered on tooth # 11.

Radiographically, a widened PDL space and broken lamina dura around the apex appeared to be in close proximity to the cutaneous lesion on the cheek. Finally, tooth # 11 had no response to pulp testing and therefore, the necessity for endodontic treatment was explained and agreed to by the patient. During initial endodontic treatment of tooth # 11, the crusty blemish began to drain when the anesthetic was administered.

Upon accessing tooth # 11, there was no odor or drainage. The canal length was determined followed by instrumentation of the canal with 6% NaOCL. The canals were medicated with CaOH paste (Ellman) and the access was sealed with a cotton pellet with Formocresol (Sultan) and Cavit (3M). Three weeks later for the fill appointment, the patient stated the cheek lesion was healing and there was no more drainage. Therefore, the canals were re-instrumented with 6% NaOCL and dried with paper points (Kerr).

The canal was sealed with Roth sealer (Roth International) and gutta percha (Diadent Group International). The access was sealed with a plain cotton pellet and Cavit (3M). Three weeks later, the patient was referred back to her general dentist for restorative treatment.

Due to the large defective proximal mesial and distal restorations, a crown was the restoration of choice. The patient returned for a 6 month re-evaluation appointment and radiographically, the apical lesion was healing well. Clinically, the cutaneous lesion healed with no scarring and the patient continued to be asymptomatic.


A chronic endodontic infection can drain onto the gingival tissue through an intraoral communication called a sinus tract. According to Baumgartner 6, this “pathway” can extend from the infection to an opening on the gingival surface called a stoma. This stoma or stomata of the intra-oral sinus tract can open up on the alveolar mucosa or the attached gingiva. They can exit through the facial or lingual tissues depending on the proximity of the apex to the cortical bone. Thus, resulting in a cutaneous oral sinus tract. According to Barrowman RA et al 1, these sinus tracts may drain onto the face depending on the relationship of the muscle attachments and tissue planes to the source of the infection. In our particular case, in the maxilla, the infection was superior to the muscle attachment. In the mandible, if the infection is inferior to the muscle attachment, a sinus tract could form on the face. Interestingly, according to Cantatore 2, cutaneous sinus tracts occur more from mandibular teeth at 80% versus maxillary teeth at 20%.

Under the heading of “It’s Not Just Semantics”, I myself, have used the word fistula to correspond with a sinus tract. This however is an incorrect term. According to the American Association of Endodontists: Glossary of Endodontic Terms, a fistula is an abnormal communication between two internal organs or a pathway between two epithelium-lined surfaces.7

According to histologic studies by Harrison and Larson and the study by Baumgartner, most sinus tracts are not lined with epithelium along their entire length. In Harrison and Larson’s study, 1 out of 10 sinus tracts studied were lined with epithelium and in Baumgartner’s study, 20 out of the 30 sinus tracts studied were not epithelial lined. 8,6 In addition, when discussing the closure of a sinus tract, the studies revealed it did not make a difference whether there was an epithelial lining or not. Closure of the sinus tract depends on a proper diagnosis, adequate endodontic treatment and healing of the apical lesion. If the sinus tract does not heal, then a re-evaluation of the endodontic procedure or looking for other etiologic factors should be in order.4 Therefore,
when discussing differential diagnosis of these sinus tracts, dental infection is the most common etiology that needs to be considered.9 Also, according to Caliskan et al, if a cutaneous sinus tract appears on the face or neck, a differential diagnosis of infection of dental origin would be in order.10 Other differential diagnosis could be osteomyolitis, actinomycosis, foreign body, pyogenic granuloma, salivary gland and duct “fistula”, suppurative lymphadenitis and neoplasm.

The most obvious treatment for a cutaneous lesion is endodontic treatment or extraction of the tooth depending on the status of the tooth. Surgical excision of the sinus tract is not necessary because closure of the sinus tract is expected in 10-14 days following correct treatment. However, healing of the cutaneous lesion is by secondary intention and may result in a scar. In this case, surgery may be needed to improve esthetics.9


We as dentists, have the ability to help our patients in both dental and medical ways. As an advocate for oral health, we can look for infections whether associated with a tooth or in rare occurrences, appear on the cheek or neck. Unfortunately, too many times, a lesion on the cheek or neck can be misdiagnosed for an extended period of time. However discouraging for the dentist, once the patient has been referred to the dental office, a diagnosis can be made and treatment of the infection can take place so we can make our patients look and feel better. Lastly, our profession needs to do more to educate physicians to be more aware of possible dental causes of facial lesions.

1 Barrowman RA, Rahimi M, Evans MD, Chandu A, Parashos P. Cutaneous sinus tracts of dental origin. Med J Aust. 2007;186(5):264-265.
2 Cantatore JL, Klein PA, Lieblich LM. Cutaneous dental sinus tract, a common misdiagnosis: a case report and review of the literature. Cutis. 2002 Nov;70(5):264-7.
3 Winstock D. Four cases of external facial sinuses of dental origin. Proc R Soc Med. 1959 Sep;52:749-51
4 Hargraves, Kenneth M., Cohen, Stephen. Pathways of the Pulp. 10th edition. Mosby Elsevier. 13: 2011.
5 Mittal N, Gupta P. Management of extraoral sinus cases: a clinical dilemna. J Endod. 2004 Jul;30(7):541-7.
6 Baumgartner JC, Picket AB, Muller JT. Microscope examination of oral sinus tracts and their associated periapical lesions. J Endod. 1984 Apr;10(4):146-52.
7 American Association of Endodontists: Glossary of Endodontic Terms, ed. 7, 2003.
8 Harrison JW, Larson WJ: The epithelized oral sinus tract: Oral Surg Oral Med Oral Pathol 1976 Oct;42(4):511-7
9 British Dental Journal: Facial Cutaneous sinuses of dental origin: a diagnostic challenge. December 2013.
10 Caliskan MK, Sen BH, Ozinel MA. Treatment of extraoral sinus tracts from traumatized teeth with apical periodontitis. Endod Dent Traumatol. 1995 Jun;11(3):115-