I had BMP applied to both the BSSO and Lefort osteotomy sites. Much more was applied to the BSSO gaps to minimize any border irregularities. Swelling was significant around those areas, but they were well clear of my airway, and dissipated well before the swelling from the surgery itself did. Notching is still noticeable to the touch, but only (slightly) visible on the left side in certain lighting.
BMP gained a bit of a bad reputation a while back when some very dumb surgeons decided to use this effective, though highly inflammatory substance, to fuse cervical (neck) vertebrae, when BMP was only approved for lumbar vertebrae fusion. I understand the appeal of a readily available homogeneous bone graft substitute, but god damn, if you're going to use it off-label maaaaaybe make sure it doesn't--you know--block the patients' airways. Since swelling due to BMP use is extremely hard/dense, hospitals even had difficulty intubating them. Scary.