The treatment suggested to you is one of the ways by which your problem can be solved. There are multiple other ways of correcting your smile like veneers, crown, orthodontic treatment without tooth extraction and so on. The treatment option that is best suited for you can be suggested only after a thorough clinical and radiographic examination.
Next Steps
get a set of extra oral rays, OPG and , LATERAL CEPHALOGRAM and get that evaluated by your orthodontist
Health Tips
do ask about the various other ways by which your problem can be sorted out and get a second opinion if your orthodontist insists on removing 4 teeth.