The easiest way to close the diastema using proximal unica matrix with composite bonding. 

Unica Proximal stainless steel matrices have a thickness of 0.03 mm and are available in two shapes (standard and deep), designed to fit the contour of the anterior teeth labially, palatally and proximally.
Unica Proximal matrices are especially indicated for anterior restorations involving the proximal walls (Class III and IV, peg-shaped lateral incisors, diastema closures, partial and total veneering).
The easy-to-place cervical labiopalatal arch has the purpose of securing the matrix between the papilla and the tooth subgingivally, in order to improve matrix stability after placement. A wedge can be used to secure the matrix but it is not mandatory.
With a shape conceived to ensure an optimal fit on the anterior teeth, it affords better visibility and operatory field access than other solutions such as posterior sectional matrices.
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