Icon Resin Infiltration - can this help reduce whiten teeth or would bonding be better?

I had my braces removed and a lingual retainer was placed on the back of my teeth. My top 2 front teeth appear darker from the middle of each tooth downward and I can't figure out if it's from my ortho removing too much of my enamel where the brackets were or if it's a shadow of the lingual retainer/glue behind my teeth. I'm really embarrassed to smile now and was wondering if Icon Resin Infiltration could help reduce this or would bonding be better.