What is a crown? 
A crown, also called a 'cap,' is a tooth-like restoration that is placed over a prepared existing tooth to restore the function, contour, appearance and strengthens the damaged tooth. Crowns serve to support the tooth when there is no longer sufficient tooth structure left to place a filling. Crowns may also be used to protect the structure of a tooth that is fractured, broken, or root canaled.
What is a bridge
?
A bridge is a custom device anchored to neighboring teeth that replaces one or more missing teeth. When a lost tooth is replaced with bridgework, the teeth on either side of the missing one must be prepared to serve as abutments to hold the pontic (replacement) teeth in place.
What Is crown and bridge treatment?
Crown and bridge treatment is a log-term method of restoring or replacing missing teeth. A crown is placed on an individual tooth. A bridge spans a 
space where one or more teeth have been lost in the dental arch. The teeth on either end of the span are crowded, and are referred to as abutments. The false teeth in a bridge that join the abutments are most often made from superior materials such as precious metals (gold), semi-precious metals, porcelain, or a combination of metal fused to porcelain. Both esthetics (appearance) and function are considered when selecting the material most suitable for you.
Why replace missing teeth?
Losing a tooth can be of social and psychological concern. Teeth are lost for a number of reasons including:
- Dental decay.
- Periodontal (gum) disease.
- Trauma (injury or accident.)
When a permanent tooth is lost, the support and chewing forces will be altered causing the adjacent teeth to shift into the vacant space. The tooth above or below to the one that was lost will begin to move up and out of place causing further breakdown in the dental arch. If the missing tooth is not replaced, more teeth will eventually be lost, due to the improper forces exerted, and the crowdness that will make plaque build up easy leading to decay and gum disease.
How should I take care of my crown and bridge?
With proper oral hygiene, including brushing and flossing at least twice a day. Also by using the dental floss threader, it will enable you to clean the replacement tooth of your bridgework.