What is porcelain inlay-onlay filling?

They are person-specific full porcelain fillings, those protect dental integrity and remain intact against chewing forces and look aesthetically at the same time, in cases of excessive dental tissue losses. They are generally used in back (molar) teeth. As porcelain inlay filling is a specific filling done for the inner segments of peaks of molar regions of teeth, porcelain onlay filling is on the other hand the larger porcelain fillings including those peaks of molar teeth.