Fragment reattachment and post reattachment bevel

Direct anteriors
16 Feb 2016

When coronal fracture occurs in anterior teeth, fragment reattachment can be a valid alternative to a direct restoration. If the fragment is available, it should be kept in a liquid environment to prevent dehydration, thus allowing a more aesthetic result after the reattachment procedure. If the fragment fits well enough, it should be reattached as it is; only after the reattachment procedure the margin should be opened with a round bur to create a double bevel on the tooth and on the fragment. This procedure is also known as post-reattachment bevel, and it will ensure esthetic results together with an increased resistance to dislocation of the fragment.
In a paper we published in 2011 (Evaluation of the fracture resistance of reattached incisal fragments using different materials and techniques. Chazine et al, Dent Traum 2011), the influence of the material and the technique used to reattach the fragment was evaluated using a shear bond strength test. Pure Adhesive, flowable composite, regular composite and dual curing resin cement were used to reattach 80 fragments. Another variable was the use or not of a post reattachment procedure as demonstrated in this article. The choice of material seemed to have no influence on the test, whereas a bevel performed on the buccal surface could significantly improve the Shear bond strength of the reattached fragment, independently of the material used for the reattachment procedure.
Tommaso, 8 years old, had a traumatic accident 2 years ago causing the fracture of tooth #2.1, which was restored in another dental office. Last august he had an additional trauma resulting in the fracture of tooth #1.1. This time the fragment was available. In the first part of this clinical case, the fragment reattachment and the margin hiding procedure is performed. In a future article the direct restoration of #2.1 will also be described.

Fig. 1

Initial situation

Fig. 2

The initial situation in occlusion

Fig. 3

The fragment, kept in milk, is correctly hydrated.

Fig. 4

Another view of the initial situation

Fig. 5

The stability of the fragment is checked.

Fig. 6

After rubber dam isolation, the fragment is stable but part of the margin and of the mesial wall is missing

Fig. 7

No preparation is performed before the fragment reattachment. This will keep the fitting to allow for a stable repositioning of the fragment

Fig. 8

Enamel selective etching on the fragment

Fig. 9

Enamel selective etching on the tooth after transparent matrix application

Fig. 10

Adhesive procedures on the fragment

Fig. 11

Adhesive procedures on the tooth

Fig. 12

A flowable material is used to reattach the fragment. Heated composite, only adhesive, or a dual curing resin cement would have been a correct alternative as well. See Chazine et al Dent Traum 2011

Fig. 13

Light curing

Fig. 14

Margin is opened with a diamond round bur. This technique is also called post reattachment bevel. (Chazine et al Dent Traum 2011)

Fig. 15

The margin opened

Fig. 16

Etching of the margin

Fig. 17

Bonding procedures

Fig. 18

application of a layer of enamel composite after a first layer of opaque flowable material

Fig. 19

Composite adaptation is achieved with the use of a brush slightly wetted with modeling resin

Fig. 20

After final curing.

Fig. 21

Finishing is performed with a low speed diamond bur. It allows to smoothen the buccal surface in a predictable way. If water cooling is not used (like in this case), a blow of air will reduce the heat generated by the bur on the surface

Fig. 22

After contouring finishing and polishing, before rubber dam removal

Fig. 23

After rubber dam removal. Teeth are dehydrated.

Fig. 24

The final result after rehydration.