Ceramic restoration can take many different forms and different methods are employed depending on the type and age of the ceramic piece. For example, the goal of restoration of centuries old or even millenia-old pottery is to make as few changes to the original construction as possible, to preserve as much information about the ceramic as possible.
As per my knowledge, ceramic conservation has a long history and a great number of materials and techniques have been employed over the years. And if you are also looking for restoring your ceramics, hire only professionals for the job.