The endo-antral syndrome

Abstract

Pulpally involved teeth, closely associated with the maxillary sinus, may not heal favorably after nonsurgical endodontic treatment. These teeth shall be considered as evidencing the endo-antral (EA) syndrome. Dental sepsis may spread via the root canal into the periapical tissues and on into an adjacent maxillary sinus. The impact often results in destruction of the bony partition along with mucosal changes that range from local necrosis to hyperplasia, cyst formation, transformation into granulation tissue, and even hyalinization. 1 A detailed discussion on this relationship can be found in a previous paper. 2 The potential for serious sequelae after antral involvement from dental sepsis has been well established, a.4 The importance of a thorough differential diagnosis is emphasized because the distinction between maxillary sinusitis and neoplastic disease can be obscure 5.6 Complete radiographic surveys including Water's projection and panoramic views have been helpful. 7,s Despite the implications of sinus complications, most pulpally related periapical lesions with apparent antral involvement seem to heal normally after root canal treatment without the need for periapical surgical intervention. The usual healing process demonstrates the disappearance of all related clinical symptoms, including the cessation of drainage through an associated sinus tract, along with radiographic evidence of restoration of bony architecture. When healing fails to occur, the signs and symptoms that characterize the EA syndrome usually include the following: the apex of an endodontically treated tooth is positioned in proximity to the maxillary sinus; the endodontic treatment (nonsurgical) is adequate; a periapical ,radiolucency has persisted and shows no indication of resolution; a perforating osseous defect through the wall of the antrum often is seen radiographically; mucosal enlargement along with an increase in sinus space opacity is usually seen; clinically, there may be a persistent draining sinus tract on the oral mucosa; tenderness to palpation on the buccal or lingual side, or both, with increased tenderness to percussion of the tooth usually occurs; and occasionally drainage of antral mucus will occur into the root canal. An early indication that a particular tooth might exhibit an EA syndrome is the failure of clinical symptoms to subside after the initial root canal treatment. This is particularly obvious with draining sinus tracts, which do not show the usual prompt improvement. In some cases the sinus tract will start to heal after the second or third treatment, only to reappear at a later date, often some weeks after canal obturation. This development will signal an EA syndrome. In some situations the presence of a perforating sinus defect can be substantiated by passing a suitable root canal instrument through the tooth into the sinus. A radiograph will aid in disclosing the presence of such a defect. Clinically, perforating sinus defects will often show a straw-colored mucous exudate that is draining into the root canal. Repeated root canal treatments will fail to permanently halt this drainage. In general, cases of EA syndrome will not respond to antibiotic therapy.