The impressions are sent to a dental laboratory where the crown will be manufactured. The crown is usually returned to be fitted in 3 weeks. If your crown is made of porcelain, your dentist will also select the shade that most closely matches the colour of the neighbouring teeth. During this first visit your dentist will make a temporary crown to cover and protect the prepared tooth while the crown is being made. Temporary crowns are usually made of acrylic and are held in place using a temporary cement.