Temporary Anchorage Devices (TADs) are tiny titanium or stainless steel screws that are used as anchors to help move teeth. An Oral Surgeon surgically inserts the TADs into your upper or lower jaw in the office with topical anesthesia. The Orthodontist can then use the TAD as an anchor to help pull a tooth in a specific direction. TADs are a relatively new innovation, and can sometimes be used in place of headgear or other appliances. After the Orthodontist achieves the desired movement, the TADs are removed. Because they are so small, they leave no lasting holes or ill effects after they are removed.
TAD insertion is not particularly painful, and they are easy to get used to; however, it is important to keep the sites of the TADs clean to prevent infection. Depending on what needs to be accomplished, you might need to wear TADs for several months to a year.
Also see the article Understanding TADs