Age 16.4. Situation after 1.2 years in braces in order to parallelize 11 and 22 for later prosthodontic rehabilitation. Teeth 24 and 25 had not been bonded because of idiopathic root resorption (compare panographic x-ray, Fig. 16). Extraorally: With and without thermoplastic retainer for temporary replacement of 21. Intraorally: Teeth 11 and 22 were parallelized.