We are more likely to be able to grow and 3d print teeth with stem cell grown pulp and nerves. Modern dentistry would become live tooth replacement as opposed to fixing decayed teeth. Multiple biotech firms have already started prototyping this approach.

The risk of selectively turning genes on and off to grow new teeth are numerous. First, cancer... did I say cancer? Second, older humans don't have the same tissue resiliency, and it is possible if not likely gums may be irreparably damaged by growing new teeth. Finally, the teeth themselves may not develop properly, multiplying the risk for things like orthodontics, TMJ, partial tooth repair, etc.

A tooth that is grown to perfectly fit the existing socket and mouth mechanics that could be successfully transplanted appears to me to be the next best option.