Tooth fragment reattachment

Majority of the traumatic dental injuries involves the anterior teeth specially the maxillary incisors. Rebonding of the fractured fragment to the tooth retrieved in a fairly intact condition provides an ultra-conservative treatment option. Rebonding techniques provide good esthetics, restores immediate function and provides positive psychological support to the patient. With the introduction of resin based material and the mono block concept, rebonding is a feasible treatment procedure.

Majority of the traumatic dental injuries involves the anterior teeth specially the maxillary incisors. Rebonding of the fractured fragment to the tooth retrieved in a fairly intact condition provides an ultra-conservative treatment option. Rebonding techniques provide good esthetics, restores immediate function and provides positive psychological support to the patient. With the introduction of resin based material and the mono block concept, rebonding is a feasible treatment procedure. These case reports discuss the techniques for rebonding fractured fragment to the tooth in a very conservative and cost-effective manner.

Traumatic fractures of the anterior teeth are a common form of dental trauma. It most commonly involves the maxillary central incisors due to its position in the arch. Fracture of the anterior teeth due to trauma requires immediate attention not only to restore immediate function and esthetics but also because of the psychological impact it has on the patient. The treatment options offered to the patient in such a situation can vary from a simple composite build up to complex restorative intervention depending on the severity of the fracture and its extent.

One of the options for restoration of fractured anterior tooth is rebonding of the fractured fragment. Rebonding of the fractured fragment should be considered only in cases where there is no or minimal violation of biological width and the fragment is retrieved in a relatively intact condition.  Tooth fragment rebonding offers a conservative, cost-effective, esthetic, functional and less time consuming alternative to the restoration of fractured tooth compared with resin based composite or full coverage crown. 

Fractured fragment reattachment offers the advantage of good and long lasting esthetics because the tooth's original anatomical form, color, and surface texture are maintained. It also restores the function and has a positive emotional and psychological response from the patient due to the preservation of natural tooth structure.

The present case report describes the successful management of two tooth fracture cases (one with and one without pulpal involvement) by fractured fragment rebonding.

The uncomplicated crown fracture of anterior teeth is the most common traumatic injury of permanent dentition.
The upper central incisors are the teeth most frequently affected by this type of dental injury (80%), and this high incidence can be related to the anterior anatomical position and to the protrusion caused by eruptive process. The traumatic events involving maxillary central incisors could also be related to malocclusion in which there is a more buccal positioning of these teeth.
Depending on different clinical situations, anterior teeth with enamel-dentin fractures can be treated using various techniques and materials. Direct or indirect restorations can be used when the fractured fragment is not available.

When the fractured portion is intact, with adequate and correctly preserved margins, the adhesive reattachment to the residual tooth structure represents the first choice treatment. The reattachment technique is also appropriate in dental fractures where the detached fragment does not match completely with the remaining tooth structure. In this case it is crucial to perform a pre-operative analysis of the margins in order to choose the best technique required to fill the gap between the tooth and the fragment thus improving the adhesion. The incisal edge reattachment technique compared with the traditional restorative procedures offers the possibility to re-establish the contour, the architecture and the original brightness of tooth easily, and with a positive emotional response and greater acceptance from the patient.

Many operative procedures have been suggested by literature, from no additional tooth preparation to various preparation options such as: circumferential bevel, internal groove, external chamfer and superficial overcontour of composite on the fracture line. Several experimental models have proved that if during tooth preparation 90% of the original tooth structure is maintained, the limit of the fracture strength of the tooth remains the same. According to Rais and Pusnam, the minimum strength for ensuring long term clinical success of the reattachment is still unknown, even if authors claims that 50% strength seems to be sufficient. With improvements in adhesives and newer materials that offer high bond strength values, some investigators have attempted to reattach fragments using these materials without an additional retentive preparation.

Clinical studies and trials have shown that the use of tooth preparation methods does not seem to improve the retention or the fracture strength of the reattached fragment. Therefore, though the experimental models point out to the necessity of making an additional tooth preparation, actual clinical research has shown a positive follow-up even in cases of reattachment without preparation. As for all the body elements that have suffered traumatic injuries, even teeth restored with the fragment reattachment technique must undergo follow-up controls.

  It is necessary to keep checking the results and the stability of the tooth-adhesive-fragment complex over time, with intraoral radiographs and clinical assessments after the treatment. The aim is to evaluate the pulp vitality and color match.

The fractured portion is disinfected with 0.2% chlorhexidine, and stored in physiologic solution to maintain the hydration. Tooth vitality test is performed by giving thermal stimulus to the tooth (cold) and it responded as vital. The first step of the operative procedure, after administration of local anaesthesia, is the isolation of the operating field with a rubber dam. Prior to the reattachment procedure, the fractured tooth is cleansed and polished; and, the fractured portion is “tried-in” to check for any presence of disruptions or defects between the remaining tooth structure and the fragment. To facilitate its handling, the fragment is fixed on its vestibular aspect to a holder with an adhesive tip

Preferably we decided to proceed with the attachment of the fractured fragment with no additional tooth preparation as there was no loss of dental hard tissues and the edges matched without any disruptions.

The fragment is treated with an “etch and rinse” technique using 37% phosphoric acid (The acid time application is related to the different tooth surface. It is 30 seconds for enamel, 15 seconds for dentine), followed by a separate application of priming and bonding agents and the fragment is kept away from light or heat sources until the reattachment phase.
The fractured tooth is etched and treated with the same adhesive system . The fragment is thus placed in its proper position on the tooth paying attention to the perfect fit between the two parts and only after this point is the bonding agent photopolymerized. The polymerization is carried out on both the vestibular and lingual aspects using a 60 seconds for each surface light-emitting diode (LED) light-curing unit . The restored tooth is then finished and polished using silicon points immediately after the fragment reattachment .

Patient is then recalled for a follow up control at 6 and 12 months. All the clinical evaluation demonstrated a good maintaining of the previous treatment with good aesthetics and function.

Wiegand et al., suggest the use of an internal groove when the residual dental structure and the fragment fit perfectly; otherwise an over contour is advisable when there is a partial loss of hard tissue.

 The primary cause of failure of the reattached tooth fragment is a new trauma or the use of the restored tooth with excessive masticatory forces, which justify many previous attempts to improve the fracture strength of the re-bonded fragment.

.

CONCLUSIONS

According to the clinical evaluation, the restoration of a fractured crown using the adhesive reattachment is the optimal treatment for an enamel-dentin fracture when the tooth fragment is available, intact and well preserved. The clinical results appear to be positive and they show that this technique is easy to perform and standardize, inexpensive, and that it allows both functional and aesthetic recovery. In fact, the reattachment technique helps avoid the silicon matrix that is required to model the palatal surface properly to create a base for the subsequent composite layering. When compared to more aggressive prosthetic techniques like crowns and veneers, the reattachment technique is both conservative and aesthetic.
Using this treatment procedure it is possible to achieve long-term retention and good mechanical resistance of the tooth-fragment complex.

Related topics :

👆 New antibacterial fillings

👆Next generation flowable composite