The importance of prompt referral when tooth roots are displaced into the maxillary antrum

It is well accepted that the apices of the roots of maxillary premolar and molar teeth are in close proximity, or directly related, to the base of the maxillary air sinus. When an upper tooth is extracted there is the potential for the creation of an oro-antral communication and the added possibility of displacement of tooth/roots into the antrum itself. The most commonly displaced tooth/root is the palatal root of the molar teeth.¹ Whenever an upper posterior tooth is to be extracted a patient should be counselled regarding the potential of the creation of an oro-antral communication and the possibility of displacement of tooth roots into the antrum itself.

A root can remain in the antrum and cause minimal adverse consequence, occasionally, however, complications arise and include acute or chronic sinusitis, the development of benign mucosal cysts/mucocoeles and antrolith formation.² Displaced roots have less commonly been reported as occluding the ostium or passing into the nose via the ostium. These have subsequently been expelled by sneezing or nose blowing or, in fact, swallowed or inhaled.³

A rare complication of any dental or sinus infection is septic thrombosis of the cavernous sinus. It is potentially life threatening and has a mortality rate of 20–30%, even with the use of appropriate antibiotics.⁴ One study demonstrated that 10% of cases of septic thrombosis of the cavernous sinus were due to dental sepsis from a maxillary tooth.⁵ Other severe complications include intracranial abscess or meningitis, eg hypertrophic pachymeningitis involving inflammatory dural thickening.⁶

We present a case of the displaced palatal root of an upper first molar tooth which was found high in the maxillary antrum. Along with other complications, such as sinusitis, it was in a high risk position for a more severe complication such as septic thrombosis of the cavernous sinus. This case report presents the safe endoscopic removal of the root, but also highlights the importance of prompt referral and treatment for similar cases to a specialist unit.

Case report

A 27-year old male was referred, on a non-urgent basis, to the Department of Oral and Maxillofacial Surgery of a district general hospital, following displacement of the palatal root of his upper left first molar tooth during a routine extraction by his general dental practitioner. He was seen 4 weeks following the procedure. The patient was fit and well and took no regular medication. His main presenting complaint was recurrent pain and draining infection out of the tooth socket and nose. He had been prescribed three courses of broad spectrum antibiotics by his dentist. No peri-apical radiograph was taken postoperatively to locate the position of the root at this stage.

On examination, there was a non-healing socket in his left maxilla with draining pus and, on performing a valsalva manoeuvre, air was visible bubbling in the socket, confirming an oral-antral fistula. Extra-orally he had no current draining pus from his nose. There was no facial swelling or tenderness. His visual acuity and eye movements were normal. An OPG radiograph was taken to re-assess the position of the UL6 root (Figure 1). It showed a clear oro-antral fistula and a grossly displaced root which appeared to be either at the uppermost part of the maxillary sinus or the base of the orbit.

A CT scan was taken which showed the displaced root remained very high in the maxillary antrum. The antrum was completely filled with fluid, demonstrating associated acute sinusitis and pus (Figure 2). The infection had not breeched the floor of the orbit and there was no current cavernous sinus thrombosis seen. The 3D reconstruction shows the position of the root perfectly and aided treatment planning (Figures 3 and 4). The authors would like to point out that the field could also be well visualized with a Cone-Beam CT (CBCT) scan to reduce the radiation dose to the patient, if this modality was available.

The following day the patient underwent the retrieval of the root via functional endoscopic sinus surgery (FESS) and closure of the oro-antral communication. A Caldwell-Luc approach for access was favoured, as opposed to through the tooth socket, as the root was high in the maxillary sinus and this approach provided better access.

The patient went home the following day and was discharged on postoperative review four weeks later as he had no complaints, was well in himself and healing was satisfactory.

Discussion

The case we present does not show a new phenomenon, but merely highlights the importance of location of the root with appropriate imaging and the prompt referral of these patients to an Oral and Maxillofacial Surgery unit, Oral Surgery unit of a teaching hospital or Specialist practitioner in the primary care setting. The general dental practitioner needs to be aware of the possibility of migration of any displaced roots, which is what developed in this case.

In this case, the root had migrated so that a general anaesthetic was required. However, in many situations with a more inferiorly placed root it is possible to retrieve these under local anaesthetic with or without the addition of intravenous sedation in trained hands. In these situations, the root can be accessed by raising a mucosal advancement flap associated with the tooth socket (Figure 5). The authors opted for a Caldwell-Luc Approach (Figure 6) for optimum access to the apex of the maxillary sinus. Either approach described would be acceptable after appropriate imaging to locate the root/s. A decision on the most appropriate access method should be made on a case-by-case basis.

In this case, functional endoscopic sinus surgery (FESS) was used. This is commonly used by Ear, Nose and Throat surgeons for access to the nasal cavity and facial sinuses. In adult cases, usually a 4 mm diameter telescope with a high-definition camera on the tip, giving excellent illumination, shows images of the sinus on a monitor. Tiny articulating instruments can then be used to perform whatever surgery is planned; in this situation the retrieval of the root from its position in superior aspect of the maxillary sinus.

Whilst the dentist's intra-oral peri-apical radiograph showed the root just above the tooth socket, the subsequent infection within the antrum led to its migration to its most superior aspect. This was then in a position considered higher risk for the rarer, but more serious complications. Some of these complications are life threatening and the possibility of which should be considered by the referring dentist.

Prompt referral to the appropriate local unit and treatment, often with a simple retrieval, reduces the potential of significant patient morbidity and mortality.