After our orthodontic treatment is complete, we all wear retainers. This is mainly because just because the teeth are lined up in a new position, it does not mean that the teeth have grown firmly in that position. Teeth grow in the alveolar bone and are surrounded by a periodontal membrane. After the teeth are arranged in a new position, the alveolar bone and periodontal membrane have to be modified to fit the new position, which takes a long process. This is why we routinely make retainers for patients to wear after orthodontic treatment is completed. For most patients, retainers are worn for two years, the first six months to a year, except for eating and drinking hot water, they are worn all day; after that, they can be worn at night. The majority of retainers nowadays are transparent, so patients do not have to worry about aesthetic issues. Some patients, such as those with periodontal disease, may have to wear retainers for life, but of course the percentage of such patients is very small. Without retainers, the malocclusion will recur. We often see patients in our clinic who relapse without the required retainer and have to be retreated, thus spending extra time and money. Retainers are an important part of treatment, so patients should wear them as prescribed by their doctors.