The Effect of Premature Extraction of the Mandibular First Deciduous Molar in the Mixed Dentition on the Eruption of Permanent Successors.

Objective To explore whethere prematurely extracting the mandibular first deciduous molar would accelerate the eruption of the permanent successors. Methods Thireeen children with crowding were selected. The unilateral mandibular first deciduous molar were removed when the root length of the mandibular first premolar attained 1/2, while the contralateral side as control. Results On the extrsction side, the eruption of mandibular first premolar was earlier in 9 cases, while all contralateral mandibular canine could make mandibular first premolar erupt earlier. However, when the mandibular premolar was impacted or canine wasn't impacted, the purpose of accelerating eruption of first premolar is hard to achieve.