Abstract
A girl, 8 years and 8 months old, with congenitally missing mandibular second premolars was treated with this altered method of serial extraction. Extraction was chosen because her teeth were large. The mandibular second deciduous molars were extracted according to following steps. First, the distal crown portion of each mandibular second deciduous molar was sliced with high-speed bar. Second, the distal crown and root portion of each mandibular second deciduous molar was hemisectioned and extracted, allowing the mandibular first molars to drift mesialy. Third, the maxillary first premolars and the mesial crown and root portion of the mandibular second deciduous molars were extracted when the mandibular first molars moved mesialy and were close to them. Finally, the mandibular first molars moved further mesially closing the space spontaneously.The extraction spaces were closed spontaneously and the dentition was in alignment until 13 years and 6 months of age. Space closure was finished after the mandibular second molars had alreadyerupted, suggesting that the mandibular third molars are especially related to the space closure.Although long-term observation was necessary in this case, this altered method of serial extraction has the advantage of using no appliances and facilitating orthodontic treatment.
