Dentist left implant crown uncemented, because the crown was stuck during trial fitting. What to do next?

I just came from what I hoped to become my last appointment for implant. Dentist tried to fit the crown cap before cementing it, but the cap stuck dead and could not be removed. The dentist sent me home, telling that there is nothing he can do now, but if the crown comes off (maybe in few days, or maybe in few years) - I could visit him again for cementing. In my opinion uncememnted crown is hazard (including potential choking hazard). What are available options? What should I do next?