Why does my nose look so different (points down) when I smile with teeth showing vs normal resting smile? (Photo)

Hello and thank you for your question.  Tip drooping with smiling is very common and is due to lack of tip support.  This can be fixed with rhinoplasty and a columellar strut graft for tip support.   Make
sure you specifically look at before and after pictures of real patients
who have had this surgery performed by your surgeon and not just a computer
animation system. The most important aspect is to find a
surgeon you are comfortable with. I recommend that you seek consultation with a
qualified board-certified plastic surgeon who can evaluate you in person.
Best wishes and good luck.
Richard G. Reish, M.D. FACS
Harvard-trained plastic surgeon

This is a very common complaint among patients seeking rhinoplasy.  You did not provide a side view, but i suspect the tip pulls down away from the bridge with smiling.  This is usually caused by 2 issues.  The first is lack of tip projection and support.  The second is probably overactivity of the depressor septi muscle. This muscle attaches to the bottom of the nose cartlage and articulates with smile muscles in the lip.  When you smile, it pulls the tip down.  Both of these issues can be addressed with rhinoplasy.  Make sure you see someone who is an expert in the field, not someone who "dabbles" in it.  

Dear Rachel, Thank you for your question. The nose is most likely tipping downwards due to the action of a muscle (depressor sept nasi) that is just under your upper lip and joins to the wall between your two nostrils (the septum). During a rhinoplasty procedure, this muscle can be separated which helps to reduce how much the nose droops. Best Wishes.

Some patients have an active depressor septi ligament which is a tether between the nasal tip and the  upper lip smile muscle.  Releasing this ligament prevents the tip from drooping when smiling dynamically.  This is usually a component of a rhinoplasty procedure.  For more information and many before and after examples of releasing the depressor septi ligament, placing link and the video below

 Peoples noses look different when they smile for three main reasons. 1)  Poor cartilage support for the tip of the nose which makes it week in susceptible to drooping 2)  hyper activity of strong depressor needs I supply muscles  3)  elevation of the upper lip and cheek while smiling can give illusion that the tip is drooping downward.  If this is a concern of yours I recommend consultation with a board-certified facial plastic surgeon. I hope this helps and wish you the best. Dr. Ardeshirpour