Front Top of Head is Egg Shaped, Can This Permanently and Safely Be Recontoured by Adding Material (Bone Paste)?

For many years now I have been bothered by the shape of the top of my head. The top front of my skull bumps up and if you were looking straight at me it would be very prominent if my head was shaved bald-I'm 30 years old and thinning. I have researched bone paste and the endoscopic approach to filling in either side of this bump to make the top of my head appear more rounded instead of looking like it comes to a point. How expensive would a procedure like this cost and is it a permanent result?