Inlays and Onlays are made by the dental technician. Inlay is similar to a filling, it is used to restore a decay or damaged tooth to its original condition. It looks completely natural.
Onlay is bigger than an inlay. It replaces one or more decayed angle.

They are made of gold or ceramics or composite.
Gold is used typically in back teeth as metal’s strength and durability.
Ceramic means porcelain aesthetics inlays or onlays. It can be coloured perfectly, it looks very natural. They are stain resistant, made to last long time.
Composites are match the tooth colour thus it’s more cosmetically pleasing than metals.

Natural tooth-white inlays- lastingness and aesthetics:
-allergy-free
-can last for more than 10 years
-restores a decay/ damage permanently
-colour and shape of inlays are matching exactly