Accidental avulsion of a recently traumatised maxillary anterior tooth during rubber dam application

Abstract

Avulsion injuries are usually seen in the anterior maxillary teeth as a result of trauma. Avulsion as an endodontic mishap is extremely rare. This report highlights an unusual instance of exarticulation of a recently traumatised maxillary central incisor tooth when the rubber dam was applied during a routine non-surgical endodontic procedure. The tooth was immediately repositioned and stabilised with wire composite splint. Endodontic treatment was initiated after rubber dam isolation with a modified technique. Calcium hydroxide was used as intracanal medicament dressing, and obturation was done after 2 weeks. The treatment was successful with uneventful periodontal healing at 24-month follow-up. The presence of well-demarcated periodontal ligament space and absence of any resorptive area on the radiograph could be defined as a successful outcome for the present case.

Background

Traumatic dental injuries (TDIs) account for 5% of all injuries.¹ These injuries affect not only the tooth but also the supporting apparatus due to transmission of the impact. The spectrum ranges from uncomplicated/complicated crown fracture, luxation injuries, and root fracture to avulsion. Mature permanent teeth with complicated crown fractures, intrusion and avulsion injuries require root canal treatment at the earliest to prevent trauma-related endodontic complications. American Association of Endodontics (2010) position statement states that ‘Tooth isolation using the dental dam is the standard of care; it is integral and essential for any non-surgical endodontic treatment’². Rubber dam isolation provides an aseptic field, improves access and visibility, decreases operative time and aids in controlling cross-infection. Endodontic therapy often requires single tooth isolation and appropriate placement of the rubber dam at the tooth is achieved by securing the clamp correctly at the cementoenamel junction. However, under certain clinical situations, a routine case on a regular day may become an emergency when an unanticipated event occurs. This article highlights a case where a recently traumatised tooth was accidentally avulsed when the rubber dam clamp was applied during endodontic therapy.

Case presentation

A 22-year-old healthy man reported to the specialty clinic with the chief report of pain in the upper right central incisor tooth (number 11). There was an alleged history of trauma 48 hours prior. Clinical examination revealed a crown fracture of tooth number 11 with evident pulpal hue from the fractured incisal edge (figure 1). The tooth was tender to palpation and percussion. Mobility was within physiological limits. Thermal (cold test) and electric pulp sensibility tests were positive. Multiple angulated intraoral periapical (IOPA) X-rays were taken to rule out root fracture (figure 2). Radiographs revealed widening of periodontal ligament (PDL) space in the apical third of the root and a radiopaque line approaching the pulp horn. A diagnosis of complicated crown fracture with concussion was made, and root canal treatment was planned. The procedure was explained to the patient, and written informed consent was obtained. Profound anaesthesia was achieved with 2% lignocaine (lignonir 2%, epinephrine 1:200,000, Aculife Healthcare, Gujarat, India). A medium thickness (0.008, 6×6 inch) rubber dam sheet (Hygienic, Coltene/Whaledent, Cuyahoga Falls, USA) was secured with the number 212 anterior clamp, with the clamp and dam placed as a single unit. While the sheet was being positioned on the frame, tooth number 11 avulsed out of the socket with the clamp in position (figure 3). Immediately the tooth was repositioned back into the socket and verified on an IOPA X-ray (figure 4). The patient was informed about this unforeseen event. A passive, non-rigid acid-etch composite wire splint was applied with a 0.4 mm orthodontic wire.

Figure 1.

Preoperative clinical photographs.

Figure 2.

Preoperative multiple angulated intraoral periapical radiographs.

Figure 3.

Avulsion of tooth number 11 after application of rubber dam clamp (number 212).

Figure 4.

Clinical picture and intraoral periapical radiograph after repositioning tooth number 11 and composite wire splint.

Isolation was achieved with a modified technique of rubber dam application to continue with the procedure. The premolar clamps were secured at the cemento-enamel junction (CEJ) of the maxillary first premolars in the right and left quadrant (tooth number 14 and tooth number 24). Here, 4-0silk sutures were used to secure the rubber dam sheet anteriorly. Liquid dam was used to enhance the seal wherever indicated (figure 5). A standardised two-visit protocol was followed for root canal treatment. A conservative access cavity was prepared with a round diamond bur (number 1013, Microdont, Sao Paulo, Brazil) and the Maillefer Endo Z bur (Dentsply/Maillefer, Tulsa, Okla) under air–water coolant. Working length was determined according to quality assurance guidelines with an electronic apex locator (Apex ID, Sybron Endo, USA) as per the manufacture’s recommendations. Thorough cleaning and shaping were done in a crown down manner with apical preparation of ISO 0.02 taper number 60 K file and copious irrigation with 5.25% sodium hypochlorite (Dentpro, Mohali, India). The canal was dried with a sterile paper point, and an intracanal medicament of calcium hydroxide slurry was placed with a lentulospiral. Sterile dry cotton pellet was placed in the access cavity and sealed with 4 mm temporary restorative material (CavitG, 3M ESPE; Germany). Postoperative instructions were given, and the patient recalled after 2 weeks according to International Association of Dental Traumatology (IADT) recommendations in case of tooth avulsion. At the subsequent visit, the patient was asymptomatic. Root canal obturation was carried out using AH-Plus sealer (Dentsply DeTreY GmbH, Germany) and lateral condensation technique. The access cavity was sealed with glass ionomer cement. The splint was removed. Aesthetic rehabilitation of tooth number 11 was done with composite (spectrum universal microhybrid composite, Dentsply DeTreY GmbH, Germany) restoration (figure 6).

Figure 5.

Modified rubber dam application technique.

Figure 6.

Postoperative clinical photograph at 2 weeks after splint removal.

Outcome and follow-up

At 24-month follow-up, the patient remained asymptomatic. Clinical examination revealed healthy periodontal tissue without any attachment loss. The mobility of the tooth was within physiological limits, and percussion produced a low, dull sound. Multiple angulated IOPA radiographs revealed intact lamina dura without any signs of root resorption. These clinical and radiographic observations suggested an uneventful healing (figures 7 and 8).

Figure 7.

Postoperative clinical photograph at 24-month follow-up.

Figure 8.

Postoperative multiple angulated intraoral periapical radiographs at 24-month follow-up.

Discussion

Type and energy of impact (E=mc²), resiliency and shape of the impacting object and direction of the impacting force are important factors determining the type of injury. Trauma with a resilient object or an impact with low velocity and high mass transfers the energy to the peri-radicular area and surrounding tissues. Labial forces result in concussion, subluxation and lateral luxation. Axial forces (ie, parallel to the tooth’s long axis) impending from incisal or apical direction would result in intrusion or extrusion/avulsion injury, respectively.³ Avulsion is the most severe form of TDIs that involves exarticulation of tooth requiring immediate attention. Avulsion of primary teeth is expected in the maxillary anterior region due to pliable and less mineralised bone with incidence varying from 5.8% to 19.4%.⁴ Avulsion in permanent teeth is less common, with a reported incidence of 0.5%–3%.⁵

The present case reports the avulsion of a permanent maxillary central incisor in dental operatory after rubber dam clamp application. When a metal clam is applied at the cementoenamel junction, a recoil closure of the gripping edges on the tooth’s surface in the vertical plane leads to a sliding movement (upward/downward). Conical rooted teeth like incisors and premolars have a predilection to ‘jump out’ of their socket when wedging forces are applied apically. In the present case, the trauma had occurred 2 days back, making the periodontal apparatus susceptible to traumatic forces. Hence, when the rubber dam clamp was being secured at the cementoenamel junction of tooth number 11 with inflamed periodontal ligament and injured periodontal fibres, recoil closure of the griping edges in the vertical plane could have led to breakdown of the already injured periodontal fibres. This could have resulted in the displacement of the tooth out of the socket. Tapashetti et al reported a similar incident where a maxillary right central incisor tooth with concussion and Ellis class II fracture avulsed during non-surgical endodontic therapy under rubber dam.⁶

Avulsion injuries cause damage to both pulp and periodontal tissue. The associated consequences can be pulp necrosis, root resorption, bone resorption and ankylosis.⁷ Time elapsed between avulsion and reimplantation is critical for maintaining fibroblasts’ vitality that translates into a favourable outcome. Donaldson and Kinirons affirmed increased root resorption when extraoral dry time exceeded 15 min.⁸ According to the IADT, extraoral dry time <20 min is ideal for a favourable outcome when the tooth is stabilised using flexible splint for up to 2 weeks.⁹ A flexible splint allows physiologic movement of the tooth, diminishing the likelihood of ankylosis.¹⁰ The affected principal periodontal fibres undergo repair and regain around two-third of strength in 2 weeks.⁹ Therefore, the tooth was immediately (<5 min) reimplanted into the socket after the avulsion and stabilised following the IADT guidelines.

The stage of root development of the tooth determines the status of the pulp in an avulsed tooth.¹¹ The pulp of an immature tooth with wide-open apex has more chances of survival than in a tooth with mature apex. A necrotic and infected pulp in a traumatised tooth act as stimulus for inflammatory root resorption. A meta-analysis by Hinckfuss and Messer established a significant correlation between delayed pulp extirpation (>14 days) and root resorption.¹² IADT recommends initiation of root canal therapy within 7–10 days after replantation of an avulsed tooth. Since, in the present case, the pulp was already exposed due to complicated crown fracture, the root canal treatment was initiated at the first visit. Calcium hydroxide was placed as an intracanal medicament because of its antiresorptive properties. The tooth was followed up for 24 months after completion of endodontic therapy. Replacement root resorption is a long-term complication of avulsion injury. However, presence of well-demarcated periodontal ligament space and absence of any resorptive area on the radiograph could be defined as a successful outcome for the present case.

The continuum of TDIs in a mature tooth may affect the tooth and the surrounding tissues like the periodontium and the alveolar bone. One must be aware of the underlying pathophysiological changes to avoid any untoward intraoperative and achieving a predictable treatment outcome. This was an unanticipated intraoperative emergency that could be managed successfully due to the available armamentarium. Based on this case’s experience, It may be postulated that splinting should be done prior to initiating root canal treatment in luxated teeth. Additionally, it is recommended to use modified rubber dam application techniques, which would preclude placement of the clamp directly on the recently traumatised tooth. The traction forces can be minimised by coating the metal clamp’s margins with a soft material and providing a broad contact area. Furthermore, alternate techniques of isolation should be considered in cases of recent traumatic injuries. A useful option is available in the form of widgets. These enable a faster and convenient mode of holding the rubber dam without using the conventional clamps. They are instrumental in the isolation of anterior teeth reducing the discomfort caused by the metal clamps. Another option includes the use of advanced rubber dams like the clampless rubber dam in which the anatomical shape and flexibility allow complete isolation of both arches without the need for clamps.¹³ Additionally, a separate rubber dam frame is not required, thus precluding the necessity of direct application of the clamp on the offending tooth.

Patient's perspective.

I am happy and satisfied with my treatment.

Learning points.

• Traumatic dental injuries affect the tooth and the attachment apparatus. Application of any direct force on the recently traumatised tooth should be avoided.

• For isolation during treatment of recently traumatised teeth, alternative techniques for rubber dam application should be employed to avoid placement of rubber dam clamp directly on the affected tooth.

• Use of widgets, coating the margins of clamps and new rubber dams available without clamps can be useful in such cases.

Ethics statements

Patient consent for publication

Obtained.