When decay eats away enamel, the resulting space is referred to as a cavity. Not treated, the decay will eventually go deeper into the tooth, and possibly cause the nerve inside to become infected. However if the cavity is caught early, we can treat it with a straightforward filling, usually in one appointment. We will first apply a topical anaesthetic to the area that requires freezing. Then with a local anaesthetic we will freeze the tooth. Then the decay can be removed leaving only solid tooth structure. Teeth with cavities may be treated with composite (white fillings), amalgam, gold, or porcelain. Each of these fillings has their advantages and disadvantages. We discuss the options with our patients to come up with an option that best fits their needs.