Depending on the amount of gap and other factors there are 3 treatment options 1. Composite filling- the gap is filled by tooth coloured material.this is the least invasive procedure 2. Ceramic veneers - very good aesthetics 3.ortho treatment or braces- at your age braces seem to be better option

Orthodontic treatment is recommended. Other alternatives are available like teeth bonding. It is a cosmetic dental treatment that makes use of a tooth-colored composite resin. Your dentist can carefully sculpt this resin into the appropriate shape and size to cover the gap between your front incisors. The gap can also be closed with veneers, but it is more costly,  requires two appointments and will be more drilling on the teeth. 

The best solution for gapping is orthodontics (braces) solution because it is stable but it will time taking. The other solution is capping if required then root canal treatment of teeth. and this is unnatural. In your oral cavity is 28 teeth then indicated that wisdom teeth is missing. They may be erupt up to 25-28 years. So don't worry for them.