Can Wearing a Splint over Nose Longer Than a Week Help Rhinoplasty Results?

Wearing it longer will not give you anything better. The surgery is the important thing in changing your nose, not wearing the splint longer than a week 

The firm nasal splint we use after surgery has little value.  The tape component does apply gentle compression to the soft tissue, in order to limit the initial swelling and give it early support.  The firm metal or moldable plastic part protects the upper third of the nose (cartilage and bone), and serves as a reminder to the patient to be careful.  It really does not have much to do with the shape of the nose.
Prolonged use of the splint adds no value.  Compression is no longer necessary for swelling reasons, and the nasal bone and cartilage are already relatively stable after the first 7-10 days.  For that reason, the trend has been for shorter duration splinting, and even no external splint in some reports.
I often employ what I tell my patients are called "nasal exercises" that help to control the final surgical result.  After the first week post op, I will demonstrate pressure points or contours that I want them to address with these maneuvers.  In my opinion, it keeps the patients invested in their final result, and helps to improve the shape and position of the subtle irregularities during healing.  This can only be done if we get the splint off at a week.