This patient was unhappy about the diastema present between his central incisors and wanted an improvement. Whitening was presented as an option, but patient was happy with the color of his teeth.

Fig.1
Pre-operative condition.

Fig.2
Rubber dam isolation is ideal in cases of diastema closure because not only it provides absolute isolation, but it retract the gingiva, allowing access for the creation of an ideal emergence profile.

Fig.3
Air-abrasion with aluminum oxide particles allows to obtain a clean surface, which is a pre-requisite for good adhesion.

Fig.4
Etching of the enamel with orthophosphoric acid.

Fig.5
A Universal adhesive is applied, the solvent is evaporated and light cured for 10 seconds (1,000mw/cm2).

Fig.6
The diastema is closed with three increments. The first tooth build up is shaped with one increment. This increment wraps around the proximal surface and fills half of the diastema. A thin bladed instrument is used to smooth and blend the increment on the buccal.

Fig.7
The thin bladed instrument is used to push the resin composite inter-proximally and palatally.

Fig.8
A flat brush is used to smooth the surface, which facilitates contouring and polishing later on. This increment is polymerized 20 seconds from the facial, and 20 seconds from the palatal aspect.

Fig.9
Teflon tape is applied to the increment to prevent adhesion while building up the proximal on tooth 21.

Fig.10
The second portion of the diastema closure is done in two increments. The first increment, the facial increment is placed and it is only building the facial half. Proper contour and smoothness is achieved with an instrument and a brush. This increment also crates the proximal contact.

Fig.11
Facial increment after polymerization and the polytetrafluoroethylene film tape removed.

Fig.12
A mylar strip is placed to help contouring the second increment on tooth 21, the palatal increment.

Fig.13
A small amount of composite resin is placed in the palatal aspect and pushed into place with an instrument.

Fig.14
The matrix is slightly pulled facially and the matrix closed, and the increment polymerized for 20 seconds.

Fig.15
Restorations are built on both central incisors so we could proceed to finishing and polishing.

Fig.16
Contouring and polishing with diamond burs and aluminum oxide discs is obtained.

Fig.17
Surface characterization is performed using a fine diamond.

Fig.18
Interproximal finishing is achieved by finishing strips.

Fig.19
Final gloss is obtained with diamond impregnated rubber cups.

Fig.20
Final result of direct composite diastema closure.

Fig.21
Smile of final result with the diastema closed.
Conclusions
The use of direct resin composite restorations allow for
1) minimally invasive dentistry by preserving enamel
2) highly esthetic restorations that satisfy even the more demanding patient
Bibliography
1. Fahl N. Step-by-Step Approaches for Anterior Direct Restorative Challenge. Journal of Cosmetic Dentistry 26(4), 42-55. 2011.
2. Paolone G. Direct composite restorations in anterior teeth. Managing symmetry in central incisors. The Int J of Esthet Dent. 9(1) 12-25, 2014.
3. Vargas M. A step-by-step approach to a diastema closure – a dual-purpose technique that manages black triangles. International Dentistry 1(3) 60-61, 2011.