Abstract: A prefabricated inlay (1) for restoring a tooth by application and fixation in a cavity prepared in the tooth and having essentially the same shape as the inlay part adapted for insertion, is provided with a pin (6) which projects from the inlay part not adapted for insertion and which is arranged to be received in an inlay holder. The whole inlay (1) is made of a material translucent to light that is suitable for curing a light-curing material used for fixing the inlay in the cavity. The inlay holder has a light source and a light guide having a tip (18) with a recess (19) for receiving the pin (6) of the inlay (1), such that the light generated by the light source can be guided through the light guide and the inlay (1) to the light-curing material.