What you're referring to is called a diagnostic wax up. Usually, it's more of a reference for the dentist rather than a useful guide for a patient because the principles of smile design are complicated and the average Joe doesn't really know what they're looking for. For that reason, I very rarely show my patients their wax ups even when they pay for them.

However, there are techniques for transferring the shape of teeth from wax ups into the mouth. If done properly, it can be pretty accurate to the wax up. It's hard to say from what you've written if that's been done, but it's hard to see why a dentist would order a wax up not to use it properly. Clearly, this is just my opinion, and your dentist may have had their reasons for what they provided.

The fact that the bonding has failed after a short time is irritating, but unfortunately common. Things to consider - did it feel like you were grinding or hitting on the tooth? Was the bonding done under rubber dam? Are any of the other fillings loose? Usually, work of this type has a year guarantee unless otherwise specified.

The good thing about bonding, by the way, is that it is usually done without drilling the underlying tooth and so is easily reversible. If it happens that this treatment is a failure, at least you'll be able to get back to normal easily.