Hi Bex

Just thought I'd let you know seen as though I have the Cerec in my mouth how it works. Once he has removed the mercury and cleaned out the tooth he takes a "map" of the cavity with a laser. This information is fed to a machine where once he has matched the color of your tooth he places the block of porcelain - which he sent you- with the bolt into a cutting machine. The bolt is there for the machine to clamp the porcelain so that when it is finished being cut to the exact proportions of your cavity he just removes the tiny piece he is going to bond to your tooth. My dentist actually let me watch mine getting cut. It was amazing to see and takes about 30 seconds. Dont be disheartened, im sure he just sent the right sample because one without the bolt in it is incomplete. My dentist had jars of pieces left from the cuting process without bolts in them that they just throw away as it is wate material, im sure yours does to and wont mind sending it to you. If you want I can get from my dentist and send you some ASAP.

If you have any questions I'll try to help you there to.
Hope this helps.

Love T.