主编访谈录

Turpin: How long did the total trial take from initial patient selection to completion of treatment for the last patient?

Xu:

The first patient was enrolled in November 1999.  The last patient was enrolled in August 2001.  The last patient completed treatment in February 2005, so it took us 6 years to finish the data collection.

Turpin: Will the success of this randomized controlled trial encourage you to initiate another trial of similar design?

Xu:

Yes, we have just started a similar RCT at the PKU orthodontic clinic.  The purpose of the new study is to compare one type of self-ligating bracket appliance with one regular bracket appliance.

Turpin: Have these somewhat surprising results caused you to change clinical teaching and the actual practice of space closure at your clinic in Peking University?

Xu:

Many of my colleagues have joined me in abandoning two-step retraction for the treatment of maximum anchorage cases.  Canine retraction is used in our clinic for other purposes including the relief of anterior crowding, the optimization of anterior alignment, and midline correction.