Diastema closure can be done without touching or altering surface if your tooth by doing braces treatment. It's the best method to choose if size of your teeth is not very small. If however you wish to do a Cosmetic alternation , then a composite build up closure can be done without reducing your tooth enamel and is not very expensive. Composites may discolour and may chip and you might need to do it again. Veneers are lens like covers from the front side of your teeth. It may require removal of slight amount of enamel. But advantage is that they don't discolour , give very natural shine and finish.
Next Steps
now that you know pros and cons of all treatments u can choose what is better suited for u