The difference between closed technique and open technique is based on the fact that whether a cut of half cm will be made on columella region along the nose. Generally patients worry that this cut might turn into a permanent scar, but this is very unlikely. Besides, this region can’t be seen from the opposite side.
The advantage of the open technique compared to the closed technique is; it provides a wide view to the surgeon and enables the surgeon to perform more easily manipulation. For this reason I prefer open technique.