Endodontic management of an unusual foreign body in a maxillary central incisor.

The discovery of foreign bodies in the teeth is often diagnosed accidentally. It is commonly seen in children. These foreign objects may act as a potential source of infection and may later lead to a painful condition. Detailed case history, clinical and radiographic examinations are necessary to come to a conclusion about the nature, size, and location of the foreign body, and the difficulty involved in its retrieval. This paper discusses the types of foreign objects found in and around the teeth and reports an unusual case of a stapler pin in the root canal of a tooth, its retrieval, and associated management of the involved teeth.

INTRODUCTION

A foreign object found in pulp chamber or root canal of a tooth is often diagnosed accidentally. It is commonly seen in children as they have the habit of placing foreign objects in the mouth. At times, these objects can get lodged in the pulp chamber or root canal of a tooth and can cause a potent focus of infection. Complications can follow if these impacted foci of infection are not eliminated. In some cases, the tooth remains asymptomatic and the presence of the foreign body is revealed only during routine radiographic examination. Presence of these objects prevents thorough instrumentation of root canal system. So, their removal is necessary to re-negotiate the canal and complete the endodontic treatment successfully.

CASE REPORT

A 14-year-old boy presented with the complaint of broken upper front teeth. The patient wanted esthetic restoration of his anterior teeth. He had a history of fall from steps while playing 2 years ago.

Clinical examination revealed a complicated crown fracture (Ellis class III) on upper right central incisor and an Ellis class II fracture on upper left central incisor [Figure 1a and b]. There was a mild discoloration of 11. He had negative history of pain, swelling, or pus discharge. On examination, an open root canal was seen on 11.

Figure 1

(a) Preoperative photograph − labial view, (b)Preoperative photograph − lingual view, (c) IOPA of upper anterior region showing foreign body in the root canal of 11, (d) Stapler pin of dimension 9 mm retrieved from the root canal, (e) Postoperative IOPA of tooth 11 (f) Postoperative photograph − labial view

An intraoral periapical radiograph revealed the presence of a radio-opaque object (foreign body) inside the root canal of 11, which resembled a bent stapler pin [Figure 1c]. It was present at the junction of middle and cervical thirds of the root canal. There was periapical radiolucency in relation to 11.

Management

The tooth 11 was isolated and a conventional access cavity was prepared. A thin, tapering, diamond fissure bur on an air rotor hand piece was used to slightly widen the orifice to facilitate access for instrumentation. An ultrasonic scaler was used to clear the debris from root canal orifice and also to facilitate loosening of the stapler pin. Root canal was irrigated with 5.2% sodium hypochlorite solution. A no. 20 H file was used to bypass and engage the foreign body. After a series of attempts, the object was moved coronally and pulled out with a mosquito forceps [Figure 1d]. The canal was then irrigated with normal saline, which helped to remove the debris including small wooden pieces. Working length was established and biomechanical preparation done using step-back technique. Calcium hydroxide was used as the intracanal medicament. In the next appointment, obturation of the tooth was done with gutta-percha using lateral condensation technique [Figure 1e]. Final restoration was done with metal ceramic crown. The tooth 21 was restored with composite [Figure 1f].

DISCUSSION

The discovery of foreign bodies in the teeth is a special situation, which is often diagnosed accidentally. Root canals or pulp chamber of a tooth can be blocked by the presence of broken instruments, canal obturation materials, and in some cases, by foreign objects inserted by the patient himself. It can occur in patients undergoing root canal treatment in which canals have been left open for drainage or after trauma. The presence of foreign body prevents thorough instrumentation of root canal system and adversely affects the outcome of successful endodontic treatment. Various objects have been reported to be lodged in the pulp chamber and root canal of teeth, such as pencil leads,[1] darning needles,[2] metal screws,[3] beads,[4] stapler pins,[5] nails, pins, wooden tooth picks, tooth brush bristles, crayons, and pieces of other plastic and wooden pieces. Actinomycosis following placement of piece of jewelry chain into a maxillary central incisor has been reported by Goldstein.[6]

Basically, the foreign objects lodged in root canal can be classified into metallic and non-metallic objects. Because of their radio-opaque nature, the metallic objects can be readily identified from routine radiographs. McAuliffe[5] summarized various radiographic methods to be followed to localize radio-opaque foreign objects, such as parallax views, vertex occlusal views, triangulation techniques, stereo radiography, and tomography. Specialized radiographic techniques such as radiovisiography and 3D computerized axial tomography (3D CAT) scans can aid in the localization. Microscopy and ultrasonic tips can be used as auxiliary tools. Non-metallic objects, being radiolucent, cannot be identified on radiographs. Hence, upon encountering resistance in a canal that was left open for a long period of time either after trauma or during endodontic treatment, it is recommended to take proper history and do careful instrumentation to prevent apical pushing of the object.

CONCLUSION

Orthograde removal of foreign objects from root canal is usually a significant challenge to the practitioners. Detailed case history taking and clinical and radiographic evaluation are necessary to come to a conclusion about the nature, size, and location of the foreign body. Careful instrumentation with patience is needed for retrieval of the foreign body. Complicated crown fractures should be managed promptly, and prolonged open drainage is avoided in children if the risks of foreign body impaction are to be minimized. There is a definite need for a proper classification of foreign bodies in and around the teeth and a treatment algorithm to be followed in such clinical situations.