Fig. 1

a Patient 1—orthopantomogram (OPT) at age of 13. Situation before extraction of the ankylosed deciduous teeth 55, 54, 65, 74, 75, 84, and 85 and start of orthodontic treatment. Eleven permanent teeth (including 4 third molars) were congenitally missing. b Patient 1—post-orthodontic situation at age of 16. The top of the mandibular processus alveolaris is small (upper). The interdental space at location of the second premolars in the maxilla is 7 and 14 mm at location of the premolars in the mandible. Six dental implants were planned (locations 15, 25, 34, 35, 44 and 45). Implant placement (inclusive bone augmentation with the autogenous retromolar mandibular bone 3 months before implant placement at the place of the 25) was postponed until the age of 18. Essix retainers were used to safeguard the width of the diastemas