Since only a qualified, professional dentist can re-implant a tooth, I find it impossible to believe he/she did not completely sterilize the tooth. I think you are creating fear where none exists. I would strongly advise you speak with the dentist who did the work for complete reassurance.
Even if your tooth HAD gotten somebody else's blood on it, and even if that blood was HIV+, you stated it was 2 HOURS before the tooth was re-implanted.........still a no risk situation. The blood had been exposed to air for all that time which would have rendered the virus inactive.
I still strongly recommend you speak with the dentist for complete peace of mind.
Vilva is correct.......you had no risk. The dentist who fixed your tooth would have sterilized it completely before putting it back in your mouth. It had also been exposed to air which renders the virus inactive.
RubyWitch