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Efficiency of serial extraction and late premolar extraction cases treated with fixed appliances
Kevin W O'Shaughnessy1, Lorne D Koroluk, Ceib Phillips
1Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, USA.
Introduction:
Severe crowding can be treated with serial extraction (SE) in the mixed dentition or with late premolar extraction (LPE) in the permanent dentition. The aim of this study was to investigate the efficiency of orthodontic treatment in SE patients and LPE patients.
Methods:
Retrospective chart review identified 51 SE patients and 49 LPE patients treated with fixed appliances. Number of appointments, length of time, and estimated total chair time were determined prior to the placement of fixed appliances and during fixed appliance treatment. Peer assessment rating (PAR) scores were obtained at T1 (start of fixed appliances) and T2 (removal of fixed appliances) for both groups, and at T0 (prior to extraction of the first premolars) for the SE group.
Results:
The mean T1 PAR score for SE patients was significantly lower than LPE patients (P <0.001); mean T2 PAR scores were not significantly different (P = 0.27). Active treatment time (T1 to T2) was significantly (P <0.001) less for SE patients than LPE patients. Total time (T0 to T2) and total number of appointments were significantly greater for the SE group compared with the LPEgroup (P <0.001).
Conclusions:
SE and LPEresulted in similar final occlusal outcomes. SEs might reduce active treatment time, but significant observation time precedes active treatment.