Is there only the one-piece molded type?
Most temporary veneers will be made of a high quality acrylic. There are several different brands names that come in a variety of colors that you can select from. Yes the veneers are normally made in one piece if multiple veneers are being made. This greatly lessens the probability of a temporary veneer coming off while waiting for the final restorations. Individual temporaries are much more likely to come off. The most important function of the temporaries besides protecting the teeth is giving you a chance to get used to the changes in color, shape, etc. that you are trying to achieve with the smile changes. It is critical that the temporaries get as close as possible to the final smile you desire so you have a chance to have input, get feedback from friends and family, etc.
If the doctor, its qualified on aesthetics, and has done many cases of makeovers, they do not need temporary veneers, no sense to make them individuals.the preparation is done after a smile design,and a good procedure, meanwhile you will have temporaries done from acrylic , which will last only some days, and the definitive ones made out of porcelain, will be set just a few days after, or even the same day, depending on the technique and materials.