During Closed Approach, Will the Scar Tissue Just Develop in the Vestibular Skin?

You are correct.  When using the “closed” endonasal approach, the external incisions are placed along the mucosal surfaces inside of the nose.  Consequently, any visible external scars are also located inside the nose. 

The various steps performed during rhinoplasty, dissection of muscles, soft tissue elevation, cartilage recontouring will also all lead to development of scar tissue.  This internal scar tissue can lead to irregularities which can sometimes be identifiable underneath the skin.    

Of the countless variables encountered during this challenging procedure, unacceptable external scarring is one of the easiest to control.  Even with an open-approach, where incisions are made of the surface of the skin, proper closure should lead to a scar which is virtually imperceptible at speaking distance.  Internal scarring is a challenge confronted in both endonasal and open-approach rhinoplasty, and is much more difficult to predict and treat.

Everything else being equal the actual amount of scar formation is not that different between open and closed rhinoplasty.

Although the opening in the external surface tissue is slightly different all of the dissection or separation of tissue layers deep to the surface is the same. Most of the scar tissue that arises is formed in these areas of tissue plane separation. The same applies to breast implants where most of the scar is really around the implant.

I hope you realize that this format of posting questions and receiving answers lacks the face to face direct communication required for you to make an informed decision regarding your surgery.

My response to your question/post does not represent formal medical advice or constitute a doctor patient relationship. You need to consult with i.e. personally see a board certified plastic surgeon in order to receive a formal evaluation and develop a doctor patient relationship.

The incisions for the closed approach are the same as an open approach with the only exception being the columellar incision.  With the closed approach there is still undermining of the entire nasal framework just like in the open rhinoplasty.  Scar tissue will develop underneath the entire nasal cartilage and bone where it was undermined.