I got my braces taken off today from the top and bottom teeth.
I have to go back in a weeks time to get a clear plastic retainer on both bottom and top teeth as prescribe from my dentist.
My friend told me that it is better to ask the dentist to put a thin wire behind my four main teeth which will stop them splitting after about 15 years.
My teeth were fine before braces apart from an overlap on my front two teeth and that is why i needed them.
Do i really need a wire on my four main teeth?
Thankyou for your time :) much appreciated.

You definitley need some kind of retention or your teeth will soon move back to where they started. A wire cemented in is very common for the lower front teeth. Sometimes the upper teeth can have a wire too but it depends on how your top and bottom teeth come together when you bite. You should talk to your orthodontist about this right away before he has the plastic retainers made.