After 5 weeks of the procedure, I went back to my surgeon for a revision.

He told me the exposed bone remains the same, it doesn't have supuration nor a rare color, so he thinks it's alright.

He knows I will lose the exposed part, but in one month more (2months +1week from surgery) he will mill the bone until he finds bleeding bone and will take out the screw. He is pretty positive that the bone will be okay for a dental implant.

I guess that on the next surgery he will have a great outlook on the bone graft, and if its really prepared for an implant. I'll let you know.