Can flaring my nostrils when yawning ruin my Rhinoplasty results?

Thank you very much for enquire.

Swelling after a rhinoplasty depends of the surgery complexity.
In this regard, the nasal swelling Post-op It can last from two weeks to two months.
To reduce this swelling, I recommend you perform delicates daily lymphatic drainage massage therapy over the face (around the nose) avoid sun exposure, and take pain/inflamation pills, as your surgeron precribe you.
Kind regards, 
Dr. Emmanuel Mallol Cotes.-  

There is no evidence that yawning will effect your rhinoplasty result in anyway.  It is best to consult with your surgeon for all your post-operative concerns.

Thank you for writing to RealSelf.The short answer is: very unlikely. Please also discuss this with your surgeon.