Crowns are custom-made tooth shaped caps which fit over your teeth. Crowns are normally made out of porcelain (for appearance) so the colour matches your existing teeth, but they can be made out of metals such as gold (for strength).
A bridge is a long-term way of filling the gap of a missing tooth/teeth. A bonded bridge requires the teeth either side of the gap to be trimmed down, and then a dental technician makes a bridge out of porcelain or metal to perfectly fit the space, with an artificial tooth supported by the teeth either side of the gap.
A mould or 3D scan of your teeth is taken and sent to a lab to custom make your crown.
Teeth that have been root filled, or have large fillings are weaker, and more likely to break when you are chewing or bite something hard. Crowns are used to protect the tooth from fracturing, and can also be used cosmetically to improve the appearance of your teeth.
Yes, because the crown is made to match your existing teeth. If you whiten your teeth later, the crown will not change colour, and will appear darker than the rest of your teeth.
The old adage, you get what you pay for applied to the crowns vs filling debate.
A crown is made from strong material that lasts much longer in your mouth. Filling such as composite are made of a hybrid plastic, which unfortunately degrades over time in the moist environment that is your mouth.
A crown is much more durable and more aesthetic, being handcrafted and colour matched to fit your tooth and mouth perfectly. Although you pay more in the short term, often people will save money in the long run. Less time getting fillings replaced, more tooth structure preserved and less time at the dentist!