Dental crowns have enhanced the life of many. These are cap-shaped that are used to cover, protect, or restore the shape, colour, or size of the original tooth PFM stands for Porcelain Fused to Metal. The outer layer of PFM is covered with porcelain. It provides good aesthetics and gives a natural appearance to the tooth. Metal is used as the base to provide strength. The porcelain layer may wear off with time and metal may become visible.