Dental braces. Close-up of orthodontic braces fixed to a patient's teeth. The mouth is held open with dental retractors. The lower incisor teeth are particularly crooked. These braces are metal brackets cemented to each tooth, connected with an adjustable wire. They are worn to correct malocclusion (poor teeth alignment on the upper and lower jaws) or teeth overcrowding. Fixed braces are used when many teeth need repositioning as they give more control over teeth movement than removable braces.