Hi..my teeth are very sensitive if i eat sweets n sugary foods..there is a sharp pain in some teeths when i eat a very sweet chocolate or dish.. Also, sometimes even if i dont eat anything, there is a pain in 1 or 2 specific teeths when i open my mouth and if air hits that part or make a specific moment.. Is there a treatment for this ? also, my teeth have mild yellow texture..can i make them white ?