An interdisciplinary approach in therapy of an adult patient is a combination of treatments among different dental professionals and beyond. The reason for this is the condition and occlusion that we find in an adult patient and this includes worn teeth, loss of tooth mass, periodontal problems and lack of individual teeth. Therefore, limitations in adult patients are the existing secondary occlusion with lack of growth potential which requires a different treatment modality than in children. Teeth that have impaired periodontal health should be primarily treated with initial periodontal therapy so that orthodontic therapy can be started at all. With a conservative periodontal approach, people with an unaesthetic gingival appearance undergo modern periodontal surgery. Lack of individual teeth, hypodontia, tilted teeth and deep bite require prosthetic care of patients that is optimized by orthodontic treatment. This creates the conditions for the basics of prosthetic or implant work. Dissatisfaction with the shape of a tooth can be resolved by restorative preparation into the appropriate shape of the tooth during or after the orthodontic treatment. In cooperation with an oral surgeon, it is possible to solve the problem of impacted canines and "redundant premolars" and this allows orthodontist a suitable situation for aligning the teeth in ideal dental arches. When orthodontic camouflage is not a possible solution, patients must be treated operatively in collaboration with a maxillofacial surgeon. With orthodontic preparation, the dental arches are brought to an ideal position independently of each other, and the jaws are operatively placed in the correct anatomical position. Today’s modern approach to the orthodontic patient is based on an interdisciplinary collaboration to enable the best possible treatment outcome.