IRCT20170928036471N1 IRCT 2017-12-13 مركز تحقيقات ناهنجاری های دندانی فكی دندان پزشکی شهید بهشتی تهران Root length evaluation after orthodontic treatment in immature teeth Root length evaluation after orthodontic treatment in immature teeth 2017-12-01 anticipated 32 Complete https://irct.ir/trial/27253 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: Randomization method: simple randomization Randomization tool: randomization table random allocation to second premolars in right and left side of mandible for determination of case or control group, Blinding description: The patients don't know that second premolar of which side of mandible get braces. The researcher and the person who measure the root length changes don't know that second premolar of which side of mandible was under orthodontic force because the periapical radiography of second premolars before treatment has no evidence of braces and also after 8 months before taking radiography of second premolars, the control tooth get brace. So nether in first periapical radiography not in second one, it is not clear that which second premolar was under force. In other hand it is not clear which tooth is in case group or control group. N/A Orthodontic care and follow up. Intervention 1: Intervention 1:apply orthodontic force on second premolar of one side of mandible by a Roth bracket system with a 0.22 slot from American Orthodontics productions, for 9 months. Intervention 2: Intervention 1:Routine care. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is The trial does not have been done yet and there is no more information.