1

Introduction

Since the mid-1980s, with the diffusion of techniques for the rehabilitation of the edentulous posterior maxilla with prostheses supported on implants, there have been reports of dental implant displacement into the paranasal sinuses . It is widely accepted that foreign bodies in the maxillary sinus should be removed surgically, even in asymptomatic patients, because they are related to ciliary function disorders that can lead to bacterial or fungal infections and chronic inflammation .

Essentially, five different surgical approaches for removing displaced dental implants from the maxillary sinus have been described in detail: (i) suction of the foreign body through the oro-antral fistula; (ii) the classical Caldwell–Luc procedure; (iii) the lateral window approach to the maxillary sinus; (iv) the transoral endoscopic approach; and (v) the nasal endoscopic procedure .

With technical improvements to nasal endoscopes, the removal of a dental implant from the maxillary sinus through a middle meatotomy has become a perfectly viable minimally-invasive procedure . The position of the displaced implant is a crucial factor, however, when adopting an endoscopic approach. The alveolar recess cannot be easy seen, mainly because of the limitations of the angulated optic system; there is often an inflammatory reaction in the maxillary mucosa surrounding the displaced implant; and concomitant nasal polyposis covering the implant has been reported in some cases.

Given the above-mentioned problems, we propose a technical modification of the standard endonasal approach through the middle meatus that involves creating an additional window through the lower meatus to afford a much wider view and a better control of the displaced implant.

2

Case report

A 40-year-old man was examined at the Maxillofacial Unit of Padova University for the displacement of a titanium osteo-integrated implant positioned about one year earlier. His dentist left the dental fixture in place and referred the patient to the Maxillofacial Unit. The patient reported no symptoms of maxillary sinusitis and revealed no oro-antral fistula. A panoramic dental radiograph and computerized tomography (CT) scan of the paranasal sinuses revealed: an implant displaced within the alveolar recess of the left maxillary sinus; concomitant sinonasal polyposis ( Fig. 1 A ); and a leftward nasal septum deviation.

(A) CT scan (coronal view): dental implant displaced in the left alveolar recess, bilateral nasal ethmoid polyposis and left maxillary polyps; (B) left middle antrostomy; (C) left lower meatotomy; (D) implant displaced in the left maxillary sinus; (E) implant removal through a left middle antrostomy; (F) CT scan (coronal view): middle antrostomy (white star) and lower meatotomy (white circle), the silastic splint is partially visible.

Septoplasty was planned, followed by endoscopic sinus surgery to remove the foreign body and treat the sinonasal polyposis.

Under general anesthesia, nasal topical anesthesia was induced with 20 ml of xylometazoline hydrochloride 1 mg/ml and lidocaine hydrochloride 20 mg/ml, volume ratio 1:1, applied for 10 min with soaked cotton pledgets. The patient underwent septoplasty through a well-standardized right hemitransfixion incision . Then bilateral anterior ethmoidectomy and frontal senotomy were performed, followed by middle meatotomy, all under a 4 mm, 0° and 45° Storz–Hopkins telescope. A complete uncinectomy was performed, then the left antrostomy was enlarged first in a dorsal-to-ventral direction (using a backward antrum punch), then in a ventral-to-dorsal direction (with a straight cutting bone punch), and finally inferiorly (with a downward antrum punch).

The ostium profile was better defined with a microdebrider using 4 mm, straight and 40°-angled shaver blades ( Fig. 1 B). The angled blades were also used to remove polyps from the maxillary sinus. The lower meatotomy was performed under a 4 mm, 45° Storz–Hopkins telescope. The left inferior turbinate was raised with a Freer elevator to display the lower meatus. Using a small antral trocar, a 1–2 cm opening was made posteriorly to the frontal edge of the inferior turbinate through the lower meatus (an angle clamp or olive-tip curved suction device could be used instead). The instruments were directed horizontally and downwards to avoid orbital injury. Straight and backward cutting bone punches were used to enlarge the opening anteriorly and posteriorly ( Fig. 1 C). A 4 mm, 45° or 70° Storz–Hopkins telescope was inserted through the opening to view the area directly, inspect the maxillary cavity and locate the dental implant ( Fig. 1 D). The microdebrider was used for further maxillary polyp removal. The implant was extracted from hypertrophic mucosa and displaced upwards, near the ostium. Under a 45° and a 70° Storz–Hopkins telescopes, the implant was grasped via the middle antrostomy with Heuwieser forceps with an extra-long curve ( Fig. 1 E).

After surgery, bilateral silastic septal splints were inserted and attached to the septum with a transfixed suture; greasy gauze was used for bilateral nasal packing for one day.

No intraoperative or postoperative complications were observed. On the 1st postoperative day, the nasal packing was removed and the patient underwent a follow-up paranasal CT scan ( Fig. 1 F); he was prescribed oral antibiotic treatment (cefpodoxime 200 mg twice a day for 6 days), oral anti-inflammatory therapy (paracetamol 1000 mg three times a day for 3 days), and daily nasal irrigations with saline solution, and discharged from hospital.

The intranasal silastic splints were removed on the 10th postoperative day, when clinical findings were normal. On the 28th postoperative day, follow-up endoscopy confirmed complete healing of the nasal cavity mucosa and spontaneous closure of the lower meatotomy.