Management of Complicated Crown Fracture by Partial Pulpotomy & Fragment Reattachment: A Case Report

Introduction

Traumatic dental injuries (TDI) account for 5% of all injuries and is a significant public health issue because of its frequency and impact on quality of life.¹ These injuries often result in trauma to dental hard tissues, pulp and are classified as enamel infarction, crown fractures (complicated & uncomplicated) and crown root fractures (complicated and uncomplicated).² When taking into account the spectrum of dental injuries, complicated and uncomplicated crown fractures are the most frequently encountered injuries, of which the incidence of complicated crown fractures is about 2-13%.³ Maxillary incisors are the most frequently involved teeth (33%) due to their position in dental arch and rigid attachment of maxilla to cranial base resulting in poor distribution of forces.⁴

Various factors should be taken into consideration during the management of these fractures, such as the time frame between trauma and initiation of treatment, level and direction of fracture line, pulpal involvement, availability of fragment, stage of root development and concomitant injury to alveolar bone and soft tissues.^4,5

Treatment approaches for the management of complicated crown fractures are carried out in two stages. In the first stage, traumatized pulp is managed by either vital pulp therapy procedures or root canal treatment. The second stage involves restoring the esthetics and function of fractured tooth by either composite build up, fragment reattachment or full coverage restorations with or without post depending on the level of fracture.⁵

Vital pulp therapy procedures like partial pulpotomy are minimally invasive and conservative approaches for reversible pulpal injuries promoting pulpal healing and hard tissue formation. With the emergence of biomimetic materials like mineral trioxide aggregate (MTA) & Biodentine, the success rate of vital pulp therapies has increased to 96%.⁶ 

When the tooth fragment is available, fragment reattachment is the best option as it helps to restore the natural tooth shape, color, translucence, surface texture, esthetics and function. Furthermore, it is a simple, fast and cost effective procedure creating positive psychological response in patients.⁷

The following case report describes the management of complicated crown fracture of a maxillary central incisor with partial pulpotomy and adhesive fragment reattachment.

Case Presentation

A 15-year-old male patient presented to the Department of Conservative Dentistry and Endodontics, Bapuji Dental College and Hospital, Davangere, with a chief complaint of fractured upper front tooth with mild sensitivity and no pain. History revealed an incident of domestic fall and patient reported to the department after two hours with the fractured tooth fragment wrapped in a tissue (Figure 1B). In order to allow the rehydration of the fragment, it was stored in saline until reattachment.

A detailed history of patient was recorded. The medical history was noncontributory. No signs of asymmetry and abnormality were observed during extra oral examination. Intraoral examination revealed an Ellis class III fracture with respect to maxillary right central incisor (Figure 1A). There were no signs of mobility, displacement, soft tissue lacerations and alveolar bone fracture. On radiographic examination, a mature permanent tooth with complicated crown fracture was seen and no periapical changes were evident (Figure 1C).

On approximation of fractured fragment to the remaining tooth, there was proper adaptation between the tooth and fragment and no gaps were evident clinically. Therefore, as a conservative treatment approach, partial pulpotomy followed by fragment reattachment was planned.

The procedure was explained to the patient and informed consent was obtained. Local anesthesia containing 2% lignocaine with 1:80,000 epinephrine was administered, followed by rubber dam isolation. Partial pulpotomy was performed using No.4 sterile round diamond bur where 2-3 mm of exposed superficial pulp was removed (Figure 2A). Cotton pellet soaked in 2.5% sodium hypochlorite was placed over the exposed pulp to achieve disinfection and hemostasis. After achieving hemostasis, MTA was placed over the amputated pulp as a capping material and was confirmed radiographically (Figure 2B & 2C). Due to the prolonged setting time of MTA and to protect the cement during subsequent etching and rinsing steps, a layer of resinmodified glass ionomer cement (RMGIC) was placed over it and cured.

Both the tooth and fragment were etched with 37% phosphoric acid for 15 sec, rinsed with water and air dried (Figure 3A & 3B). Scotch Bond universal bonding agent was applied to both for 10 sec and air thinned (Figure 3C & 3D). Fragment reattachment was done using flowable composite as an intermediate material and cured (BG Bludent) from both buccal and palatal aspects for 20 seconds each (Figure 3E). After removing the excess composite, finishing and polishing was done. Final radiograph was taken to ensure adequate approximation of fragments and absence of excess composite resin (Figure 4A, 4B & 4C).

Follow up was done at intervals of 1, 3 and 6 months. The tooth was observed to be vital when tested using cold test during the follow up visits. No clinical symptoms and periapical pathologies were noted and the tooth was functionally and esthetically acceptable (Figure 4C, 4D & 4E).

Discussion

In an era of minimally invasive dentistry, the management of traumatic injuries must prioritize the concept of minimal intervention and maximal perseveration of biological tissues. In the present case, treatment strategy employed included partial pulpotomy for the preservation of pulp vitality and fragment reattachment for esthetic and functional rehabilitation of tooth.

According to International Association of Dental Traumatology (IADT), vital pulp therapy is the recommended treatment of choice for traumatic dental injuries with pulp exposure in young patients.³ However, the decision for vital pulp therapy should be based on the status of pulpal inflammation and expected prognosis.⁵ The present case had specific prognostic factors for vital pulp therapy like young patient, trauma induced small pulp exposure, reduced time lag between trauma and initiation of treatment, control of pulpal hemorrhage within five minutes and an underlying healthy pulp stump.³ According to Cvek et al., the reported success rate for partial pulpotomy procedures after complicated crown fracture is 96%.⁸ Various materials have been proposed in the literature for capping the amputated pulp, of which calcium hydroxide has been the material of choice for a long time.⁹ With the advent of biomimetic materials like MTA, the success of partial pulpotomy has increased to 95 – 99.8%.10 In this case report, MTA was used as the capping material as it induces dentinal bridge formation at a faster rate with greater structural integrity and less tunnel defects, thereby providing more effective seal against microbial penetration.

With the advent of adhesive dentistry, fragment reattachment has become a more reliable and simplified treatment for the esthetic and functional rehabilitation of tooth in TDI. When compared to other procedures, it is more conservative, cost effective, less time consuming and offers many advantages like maintenance of natural tooth color, form, alignment, surface texture and translucency.⁷

Several techniques have been proposed in the literature for fragment reattachment. Some authors recommend tooth preparation in the form of dentinal grooves, chamfer or bevels to increase the fracture resisitance.^11,12 However, a recent systematic review concluded that simple reattachment is currently the preferred technique as it decreases the technical sensitivity of procedure and treatment time.⁷ Thus in this case report, simple reattachment involving a bonding procedure with flowable composite as an intermediate material with no additional preparation was performed.

Other important aspects of fragment reattachment include the choice of adhesive system and the intermediate material used. According to Pusman & Cehrell, regardless of adhesive systems used, reattachment with composite resin as the intermediate material increases the fracture strength of reattached fragment.¹³ Hydration of fracture fragment also has a considerable effect on the fracture strength and natural esthetic appearance of the tooth. According to Shirani et al., ²⁴ hour rehydrated specimens exhibited higher bond strength compared to specimens with 30 minutes of rehydration. The authors also concluded that if dehydration time is 30 minutes or less, rehydration for 30 minutes significantly increased the adhesive strength of reattached fragment.¹⁴ Poubel et al., evaluated the effect of dehydration and rehydration intervals on the fracture resistance of reattached fragments using multimode adhesives.¹⁵ Authors concluded that rehydration for 15 minutes provided sufficient moisture to increase the reattachment strength when using multimode adhesives. A recent systematic review concluded that the longevity of tooth with reattached fragment is comparable to the direct composite restoration with the survival rate ranging from 80 – 88.9%.¹⁶

Complicated crown fractures can be successfully managed following the minimally invasive procedures like pulpotomy and fragment reattachment. However, proper diagnosis, assessment of positive and negative prognostic determinants and patient acceptance should be considered prior to the treatment to achieve predictable success. Long term follow up visits are required to assess the outcome and to manage any further complications.

Conflicts of Interest

Nil