<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03256279</url>
  </required_header>
  <id_info>
    <org_study_id>UniCIEO</org_study_id>
    <nct_id>NCT03256279</nct_id>
  </id_info>
  <brief_title>Mechanical Properties and Clinical Efficacy of Two Nickel-Titanium (NiTi) Archwires</brief_title>
  <acronym>(NiTi)</acronym>
  <official_title>Comparison of Mechanical Properties and Clinical Efficacy Between Heat-activated and Superelastic Nickel-Titanium (NiTi) Archwires.</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Fundación Universitaria CIEO</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Fundación Universitaria CIEO</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Objective: to compare the changes of the mechanical properties measured by tensile test and&#xD;
      three point bending test of two NiTi archwires (heat-activated and superelastic); when&#xD;
      exposed to the oral conditions during the first three months of orthodontic treatment and to&#xD;
      evaluated their clinical efficacy in lower arch crowding resolution in the anterior&#xD;
      mandibular arch.&#xD;
&#xD;
      Methods: Randomized clinical trial in 54 orthodontic patients with moderate crowding. They&#xD;
      are going to be randomly assigned in to two intervention groups, each group with 27 patients.&#xD;
      One group are going to be treated with heat-activated NiTi archwires and the other group with&#xD;
      superelastic NiTi archwires. The patients are going to be followed up for three months and&#xD;
      cast models will be taken every month. Measures of anterior lower arch crowding resolution&#xD;
      are going to be taken by previously-calibrated operators. Six archwires of each group will be&#xD;
      chosen at random and will have tensile test and three-point bending test and the mechanical&#xD;
      properties are going to measure before and after its clinical use. The outcomes are going to&#xD;
      be determined and compared between groups, with correspondent statistical test and the&#xD;
      results are going to be analyzed.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      PICO QUESTION:&#xD;
&#xD;
        -  Does the amount of the resolution of the anterior lower arch crowding increase in the&#xD;
           patients with superelastic NiTi archwire compared with the patients with heat-activated&#xD;
           NiTi archwire during the first three months of orthodontic treatment and/or its&#xD;
           mechanical properties change after three months of clinical use?&#xD;
&#xD;
      Population: Orthodontic patients with moderate anterior mandibular crowding Intervention:&#xD;
      .014&quot; Superelastic NiTI archwire (3M Unitek, Monrovia, CA) Comparison: .014&quot; Heat activated&#xD;
      NiTi archwire (3M Unitek, Monrovia, CA)&#xD;
&#xD;
      Outcomes:&#xD;
&#xD;
      Primary Outcomes:&#xD;
&#xD;
        -  Quantity of resolution of anterior mandibular crowding every month for three months&#xD;
&#xD;
        -  Mechanical properties measured by tensile test and three point bending test before and&#xD;
           after the three first months of orthodontic treatment.&#xD;
&#xD;
      Secondary Outcomes: Archwires deformation under oral conditions during the first three months&#xD;
      of the orthodontic treatment.&#xD;
&#xD;
      AIMS&#xD;
&#xD;
      GENERAL AIM To compare the changes of the mechanical properties measured by tensile test and&#xD;
      three point bending test of two NiTi archwires (heat-activated and super-elastic); when&#xD;
      exposed to the oral conditions during the first three months of orthodontic treatment and to&#xD;
      evaluated the clinical efficacy in lower anterior arch crowding resolution.&#xD;
&#xD;
      SPECIFIC AIMS&#xD;
&#xD;
        -  To recruit 54 orthodontic patients, 13-25 years old, without extraction into a&#xD;
           randomized clinical trial design, single-blinded trial, into the effects of NiTi&#xD;
           arch-wires alloy in the resolution of the anterior mandibular crowding during the three&#xD;
           first months of the orthodontic treatment.&#xD;
&#xD;
        -  To test the hypothesis that, compared the resolution of the anterior mandibular crowding&#xD;
           in the first three months of orthodontic treatment, with those to receive NiTi&#xD;
           heat-activated arch-wire, those assigned to receive superelastic NiTi archwire&#xD;
&#xD;
        -  More amount of resolution of the anterior mandibular crowding&#xD;
&#xD;
        -  Differences in the changes of mechanical properties after clinical use&#xD;
&#xD;
        -  Less archwire deformation&#xD;
&#xD;
      METHODS&#xD;
&#xD;
      OVERVIEW OF DESIGN Study Design: Randomized clinical trial&#xD;
&#xD;
        -  Randomized clinical trial in 54 orthodontic patients with moderate crowding. They are&#xD;
           going to be randomly assigned in to two intervention groups, each group with 27&#xD;
           patients. One group are going to be treated with heat-activated NiTi archwires and the&#xD;
           other group with super-elastic NiTi archwires.&#xD;
&#xD;
        -  Blinding: It is not possible to blind patients and clinical staff, but we are going to&#xD;
           blind the operators who will perform the measurements and the data analysis&#xD;
           (single-blinded).&#xD;
&#xD;
      We are going to have an exact clinical protocol for both groups with the only difference&#xD;
      being in the NiTI arch-wire alloy.&#xD;
&#xD;
      MBT prescription .022 slot. Alginate impressions and cast models at the beginning of the&#xD;
      study, immediately after the first, second and third month of the orthodontic treatment.&#xD;
&#xD;
      Measures of anterior lower arch crowding resolution are going to be taken by&#xD;
      previously-calibrated operators.&#xD;
&#xD;
      Arch-wires deformation are going to be evaluated by visual observation every month in monthly&#xD;
      clinical visits.&#xD;
&#xD;
      The measures of the mechanical properties measured by tensile test and three point bending&#xD;
      test of two NiTi archwires (heat-activated and super-elastic); are going to take before and&#xD;
      after the first three months of orthodontic treatment.&#xD;
&#xD;
      DESIGN FOR SAMPLING&#xD;
&#xD;
      Study Population:&#xD;
&#xD;
      - Orthodontic patients from the orthodontic department clinic of the UniCIEO&#xD;
&#xD;
      Sampling:&#xD;
&#xD;
        -  No probabilistic: convenience sample&#xD;
&#xD;
        -  Consecutive sample of consenting patients&#xD;
&#xD;
      PLANS FOR RECRUITMENT&#xD;
&#xD;
      Patients of the Clinic University (UniCIEO) that meet the selection criteria and accept to&#xD;
      participate.&#xD;
&#xD;
      MEASUREMENTS&#xD;
&#xD;
      MAIN PREDICTOR VARIABLE&#xD;
&#xD;
      - Type of NiTi Alloy used (NiTi superelastic arch-wire; NiTi heat-activated arch-wire)&#xD;
&#xD;
      POTENCIAL CONFOUNDING VARIABLES - Age&#xD;
&#xD;
      - Sex&#xD;
&#xD;
      OUTCOME VARIABLES&#xD;
&#xD;
      Plaster models Outcomes:&#xD;
&#xD;
      - Quantity of anterior mandibular crowding resolution measured monthly&#xD;
&#xD;
      Mechanical Properties Outcomes:&#xD;
&#xD;
      - Measured in vitro with an Instrom before and after three months of the orthodontic&#xD;
      treatment by tensile test and three point bending test&#xD;
&#xD;
      Archwire Outcomes:&#xD;
&#xD;
      - Archwire deformation measure at monthly visit, by visual evaluation&#xD;
&#xD;
      STATISTICAL ISSUES&#xD;
&#xD;
      APPROACH TO STATISTICAL ANALYSIS&#xD;
&#xD;
      The data will be processed in the statistics program Stata 14 (Stata Corp 2011. Stata&#xD;
      Statistical Software: Release 14. College Station, TX: Stata Corp LP). Qualitative variables&#xD;
      are going to be described by frequencies and percentages; quantitative variables will resume&#xD;
      as average and standard deviation. The association between qualitative variables will be&#xD;
      calculated by Chi-square test. For two group comparisons, we are going to use the t test or&#xD;
      Wilcoxon-Mann-Whitney test. Significance level is going to be set at P&lt;0.05.&#xD;
&#xD;
      HYPOTHESIS, SAMPLE SIZE AND POWER&#xD;
&#xD;
      Hypothesis:&#xD;
&#xD;
      Null Hypothesis H0: compared the resolution of the anterior mandibular crowding in the first&#xD;
      three months of orthodontic treatment, with those to receive NiTi heat-activated archwire,&#xD;
      those assigned to receive superelastic NiTi archwire&#xD;
&#xD;
        -  Same amount of resolution of the anterior mandibular crowding&#xD;
&#xD;
        -  Same changes in mechanical properties after clinical use&#xD;
&#xD;
        -  Same archwire deformation&#xD;
&#xD;
      Alternate Hypothesis Ha: compared the resolution of the anterior mandibular crowding in the&#xD;
      first three months of orthodontic treatment, with those to receive NiTi heat-activated&#xD;
      archwire, those assigned to receive superelastic NiTi archwire&#xD;
&#xD;
        -  More amount of resolution of the anterior mandibular crowding&#xD;
&#xD;
        -  Differences in the changes of mechanical properties after clinical use&#xD;
&#xD;
        -  Less archwire deformation&#xD;
&#xD;
      Sample size calculation and power:&#xD;
&#xD;
      It was calculated with the software Epidat (software Epidat version 4.1). With 90% power and&#xD;
      a 5% level of significance and with standard deviation data from a previous study, the sample&#xD;
      should comprise at least 27 patients per group.&#xD;
&#xD;
      QUALITY CONTROL AND DATA MANAGEMENT&#xD;
&#xD;
      Bias Control:&#xD;
&#xD;
      Selection bias:&#xD;
&#xD;
      - Randomization&#xD;
&#xD;
      Information bias:&#xD;
&#xD;
        -  The principal investigators are going to train the observers in the theoretical and&#xD;
           practical issues of all the measures of the variables of this study developing an&#xD;
           operations manual.&#xD;
&#xD;
        -  The observers are going to be calibrated and evaluated in intra and extra observer&#xD;
           concordance by Bland Altman plot with previously fixed acceptable limits.&#xD;
&#xD;
        -  All variables, are going to be re-measured after two weeks in subjects randomly&#xD;
           selected.&#xD;
&#xD;
        -  Random and systematic errors are going to be calculated with Dahlberg´s formula and&#xD;
           dependent t test, respectively.&#xD;
&#xD;
        -  Same clinical protocol for groups, the only difference in the intervention. All clinical&#xD;
           and laboratory procedures will meet quality standards. The research team will take care&#xD;
           of the data in order to be reliable and accurate The research team will take care that&#xD;
           complete and accurate records will be maintained Statistical methods are going to be&#xD;
           pre-specified and carefully followed The results are going to be clearly and fairly&#xD;
           reported&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Recruiting</last_known_status>
  <start_date type="Actual">July 8, 2017</start_date>
  <completion_date type="Anticipated">December 10, 2019</completion_date>
  <primary_completion_date type="Anticipated">December 10, 2019</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <primary_purpose>Health Services Research</primary_purpose>
    <masking>Double (Participant, Outcomes Assessor)</masking>
    <masking_description>Only one of the investigators are going to know the archwire assigment, the other ones who are going to do the measures are going to be blinded.</masking_description>
  </study_design_info>
  <primary_outcome>
    <measure>Quantity of anterior mandibular crowding resolution</measure>
    <time_frame>baseline and three months</time_frame>
    <description>MBT prescription .022 slot. Alginate impressions and cast models at the beginning of the study, immediately after the first, second and third month of the orthodontic treatment.&#xD;
Measures of anterior lower arch crowding resolution are going to be taken by previously-calibrated operators.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Changes in Mechanical properties</measure>
    <time_frame>baseline and three months</time_frame>
    <description>Mechanical properties of six archers random choose per group are going to be measured by tensile test and three-point bending test, before and three months after clinical use.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Archwire deformation</measure>
    <time_frame>baseline and three months</time_frame>
    <description>Archwire deformation will be measure by visual evaluation, each month of clinical use</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Anticipated">54</enrollment>
  <condition>Crowding of Anterior Mandibular Teeth</condition>
  <arm_group>
    <arm_group_label>Heat-activated archwire</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>.014&quot; NiTi heat-activated archwire in the lower arch during the first three months of the orthodonci treatment</description>
  </arm_group>
  <arm_group>
    <arm_group_label>superelasticwire</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>This arm are going to receive .014&quot; NiTi Superelastic archwire in the lower arch during the first three months of the orthodonci treatment</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>.014&quot; NiTi heat-activated archwire</intervention_name>
    <description>.014&quot; NiTi heat-activated archwire In the lower arch during the first three months of the orthodonci treatment</description>
    <arm_group_label>Heat-activated archwire</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>.014&quot; NiTi Superelastic archwire</intervention_name>
    <description>.014&quot; NiTi superelastic archwireIn the lower arch during the first three months of the orthodonci treatment</description>
    <arm_group_label>superelasticwire</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Orthodontic treatment without extraction with moderate anterior mandibular crowding&#xD;
             (little index: 4-6mm)&#xD;
&#xD;
          -  Age range between 15-25 years' old&#xD;
&#xD;
          -  Non gingivitis or untreated caries at the start of orthodontic treatment&#xD;
&#xD;
          -  Not need for intermaxillary elastics, striping, open compressed Nit springs, active&#xD;
             labial arch, stainless ligature, during the first to the third months of orthodontic&#xD;
             treatment&#xD;
&#xD;
          -  Complete orthodontic appliances in the lower arch (at minimum from first molar to the&#xD;
             first molar)&#xD;
&#xD;
        Exclusion criteria:&#xD;
&#xD;
          -  Patients with systemic disease&#xD;
&#xD;
          -  Medicated patients (long term use of antibiotics, Phenytoin, cyclosporine, anti-&#xD;
             inflammatory drugs, systemic corticosteroids, and calcium channel blockers)&#xD;
&#xD;
          -  Diseases that may affect dental movement&#xD;
&#xD;
          -  Syndromic patients&#xD;
&#xD;
          -  Patients with a history of trauma and/or root resorption at the lower arch&#xD;
&#xD;
          -  Patients who do not attend more than one month to the appointment&#xD;
&#xD;
          -  Lower .014&quot; NiTi archwires that fracture during the first three months of the study.&#xD;
&#xD;
          -  Patients with previous orthodontic treatment&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>13 Years</minimum_age>
    <maximum_age>25 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Sonia Plaza, Ms.</last_name>
    <role>Study Director</role>
    <affiliation>Fundación Universitaria CIEO</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Suly Amaya, DDS</last_name>
    <phone>315 783 72 45</phone>
    <email>sulyamgo@yahoo.es</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Humberto Guzman, DDS</last_name>
    <phone>315 3871090</phone>
    <email>tesisalambres@gmail.com</email>
  </overall_contact_backup>
  <location>
    <facility>
      <name>Orthodontic clinic of Post-graduation program UniCIEO</name>
      <address>
        <city>Bogota</city>
        <state>Bogotá D. C.</state>
        <zip>11011</zip>
        <country>Colombia</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>HUMBERTO GUZMAN, DDS</last_name>
      <phone>315 382 10 90</phone>
      <email>tesisalambres@gmail.com</email>
    </contact>
    <contact_backup>
      <last_name>SULY AMAYA, DDS</last_name>
      <phone>315 783 72 45</phone>
      <email>sulyamgo@yahoo.es</email>
    </contact_backup>
    <investigator>
      <last_name>Suly Amaya, DDS</last_name>
      <role>Principal Investigator</role>
    </investigator>
    <investigator>
      <last_name>Humberto Guzman, DDS</last_name>
      <role>Sub-Investigator</role>
    </investigator>
    <investigator>
      <last_name>Alexandra Perez, DDS</last_name>
      <role>Sub-Investigator</role>
    </investigator>
    <investigator>
      <last_name>Juan David Mojica, DDS</last_name>
      <role>Sub-Investigator</role>
    </investigator>
    <investigator>
      <last_name>Grecia Mota</last_name>
      <role>Sub-Investigator</role>
    </investigator>
    <investigator>
      <last_name>Andres Espinoza</last_name>
      <role>Sub-Investigator</role>
    </investigator>
  </location>
  <location_countries>
    <country>Colombia</country>
  </location_countries>
  <verification_date>September 2019</verification_date>
  <study_first_submitted>August 16, 2017</study_first_submitted>
  <study_first_submitted_qc>August 16, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">August 22, 2017</study_first_posted>
  <last_update_submitted>September 27, 2019</last_update_submitted>
  <last_update_submitted_qc>September 27, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">October 1, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Fundación Universitaria CIEO</investigator_affiliation>
    <investigator_full_name>Suly Amaya</investigator_full_name>
    <investigator_title>Teacher Orthodontic department</investigator_title>
  </responsible_party>
  <keyword>Orthodontic Wires</keyword>
  <keyword>Alloys/therapeutic use</keyword>
  <keyword>Orthodontics, corrective</keyword>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03256279
org study id: UniCIEO
nct id: NCT03256279
lead sponsor: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
Objective: to compare the changes of the mechanical properties measured by tensile test and
      three point bending test of two NiTi archwires (heat-activated and superelastic); when
      exposed to the oral conditions during the first three months of orthodontic treatment and to
      evaluated their clinical efficacy in lower arch crowding resolution in the anterior
      mandibular arch.

      Methods: Randomized clinical trial in 54 orthodontic patients with moderate crowding. They
      are going to be randomly assigned in to two intervention groups, each group with 27 patients.
      One group are going to be treated with heat-activated NiTi archwires and the other group with
      superelastic NiTi archwires. The patients are going to be followed up for three months and
      cast models will be taken every month. Measures of anterior lower arch crowding resolution
      are going to be taken by previously-calibrated operators. Six archwires of each group will be
      chosen at random and will have tensile test and three-point bending test and the mechanical
      properties are going to measure before and after its clinical use. The outcomes are going to
      be determined and compared between groups, with correspondent statistical test and the
      results are going to be analyzed.
PICO QUESTION:

        -  Does the amount of the resolution of the anterior lower arch crowding increase in the
           patients with superelastic NiTi archwire compared with the patients with heat-activated
           NiTi archwire during the first three months of orthodontic treatment and/or its
           mechanical properties change after three months of clinical use?

      Population: Orthodontic patients with moderate anterior mandibular crowding Intervention:
      .014" Superelastic NiTI archwire (3M Unitek, Monrovia, CA) Comparison: .014" Heat activated
      NiTi archwire (3M Unitek, Monrovia, CA)

      Outcomes:

      Primary Outcomes:

        -  Quantity of resolution of anterior mandibular crowding every month for three months

        -  Mechanical properties measured by tensile test and three point bending test before and
           after the three first months of orthodontic treatment.

      Secondary Outcomes: Archwires deformation under oral conditions during the first three months
      of the orthodontic treatment.

      AIMS

      GENERAL AIM To compare the changes of the mechanical properties measured by tensile test and
      three point bending test of two NiTi archwires (heat-activated and super-elastic); when
      exposed to the oral conditions during the first three months of orthodontic treatment and to
      evaluated the clinical efficacy in lower anterior arch crowding resolution.

      SPECIFIC AIMS

        -  To recruit 54 orthodontic patients, 13-25 years old, without extraction into a
           randomized clinical trial design, single-blinded trial, into the effects of NiTi
           arch-wires alloy in the resolution of the anterior mandibular crowding during the three
           first months of the orthodontic treatment.

        -  To test the hypothesis that, compared the resolution of the anterior mandibular crowding
           in the first three months of orthodontic treatment, with those to receive NiTi
           heat-activated arch-wire, those assigned to receive superelastic NiTi archwire

        -  More amount of resolution of the anterior mandibular crowding

        -  Differences in the changes of mechanical properties after clinical use

        -  Less archwire deformation

      METHODS

      OVERVIEW OF DESIGN Study Design: Randomized clinical trial

        -  Randomized clinical trial in 54 orthodontic patients with moderate crowding. They are
           going to be randomly assigned in to two intervention groups, each group with 27
           patients. One group are going to be treated with heat-activated NiTi archwires and the
           other group with super-elastic NiTi archwires.

        -  Blinding: It is not possible to blind patients and clinical staff, but we are going to
           blind the operators who will perform the measurements and the data analysis
           (single-blinded).

      We are going to have an exact clinical protocol for both groups with the only difference
      being in the NiTI arch-wire alloy.

      MBT prescription .022 slot. Alginate impressions and cast models at the beginning of the
      study, immediately after the first, second and third month of the orthodontic treatment.

      Measures of anterior lower arch crowding resolution are going to be taken by
      previously-calibrated operators.

      Arch-wires deformation are going to be evaluated by visual observation every month in monthly
      clinical visits.

      The measures of the mechanical properties measured by tensile test and three point bending
      test of two NiTi archwires (heat-activated and super-elastic); are going to take before and
      after the first three months of orthodontic treatment.

      DESIGN FOR SAMPLING

      Study Population:

      - Orthodontic patients from the orthodontic department clinic of the UniCIEO

      Sampling:

        -  No probabilistic: convenience sample

        -  Consecutive sample of consenting patients

      PLANS FOR RECRUITMENT

      Patients of the Clinic University (UniCIEO) that meet the selection criteria and accept to
      participate.

      MEASUREMENTS

      MAIN PREDICTOR VARIABLE

      - Type of NiTi Alloy used (NiTi superelastic arch-wire; NiTi heat-activated arch-wire)

      POTENCIAL CONFOUNDING VARIABLES - Age

      - Sex

      OUTCOME VARIABLES

      Plaster models Outcomes:

      - Quantity of anterior mandibular crowding resolution measured monthly

      Mechanical Properties Outcomes:

      - Measured in vitro with an Instrom before and after three months of the orthodontic
      treatment by tensile test and three point bending test

      Archwire Outcomes:

      - Archwire deformation measure at monthly visit, by visual evaluation

      STATISTICAL ISSUES

      APPROACH TO STATISTICAL ANALYSIS

      The data will be processed in the statistics program Stata 14 (Stata Corp 2011. Stata
      Statistical Software: Release 14. College Station, TX: Stata Corp LP). Qualitative variables
      are going to be described by frequencies and percentages; quantitative variables will resume
      as average and standard deviation. The association between qualitative variables will be
      calculated by Chi-square test. For two group comparisons, we are going to use the t test or
      Wilcoxon-Mann-Whitney test. Significance level is going to be set at P<0.05.

      HYPOTHESIS, SAMPLE SIZE AND POWER

      Hypothesis:

      Null Hypothesis H0: compared the resolution of the anterior mandibular crowding in the first
      three months of orthodontic treatment, with those to receive NiTi heat-activated archwire,
      those assigned to receive superelastic NiTi archwire

        -  Same amount of resolution of the anterior mandibular crowding

        -  Same changes in mechanical properties after clinical use

        -  Same archwire deformation

      Alternate Hypothesis Ha: compared the resolution of the anterior mandibular crowding in the
      first three months of orthodontic treatment, with those to receive NiTi heat-activated
      archwire, those assigned to receive superelastic NiTi archwire

        -  More amount of resolution of the anterior mandibular crowding

        -  Differences in the changes of mechanical properties after clinical use

        -  Less archwire deformation

      Sample size calculation and power:

      It was calculated with the software Epidat (software Epidat version 4.1). With 90% power and
      a 5% level of significance and with standard deviation data from a previous study, the sample
      should comprise at least 27 patients per group.

      QUALITY CONTROL AND DATA MANAGEMENT

      Bias Control:

      Selection bias:

      - Randomization

      Information bias:

        -  The principal investigators are going to train the observers in the theoretical and
           practical issues of all the measures of the variables of this study developing an
           operations manual.

        -  The observers are going to be calibrated and evaluated in intra and extra observer
           concordance by Bland Altman plot with previously fixed acceptable limits.

        -  All variables, are going to be re-measured after two weeks in subjects randomly
           selected.

        -  Random and systematic errors are going to be calculated with Dahlberg´s formula and
           dependent t test, respectively.

        -  Same clinical protocol for groups, the only difference in the intervention. All clinical
           and laboratory procedures will meet quality standards. The research team will take care
           of the data in order to be reliable and accurate The research team will take care that
           complete and accurate records will be maintained Statistical methods are going to be
           pre-specified and carefully followed The results are going to be clearly and fairly
           reported
allocation: Randomized
intervention model: Parallel Assignment
primary purpose: Health Services Research
masking: Double (Participant, Outcomes Assessor)
masking description: Only one of the investigators are going to know the archwire assigment, the other ones who are going to do the measures are going to be blinded.
measure: Quantity of anterior mandibular crowding resolution
time frame: baseline and three months
description: MBT prescription .022 slot. Alginate impressions and cast models at the beginning of the study, immediately after the first, second and third month of the orthodontic treatment.
Measures of anterior lower arch crowding resolution are going to be taken by previously-calibrated operators.
measure: Changes in Mechanical properties
time frame: baseline and three months
description: Mechanical properties of six archers random choose per group are going to be measured by tensile test and three-point bending test, before and three months after clinical use.
measure: Archwire deformation
time frame: baseline and three months
description: Archwire deformation will be measure by visual evaluation, each month of clinical use
arm group label: Heat-activated archwire
arm group type: Experimental
description: .014" NiTi heat-activated archwire in the lower arch during the first three months of the orthodonci treatment
arm group label: superelasticwire
arm group type: Active Comparator
description: This arm are going to receive .014" NiTi Superelastic archwire in the lower arch during the first three months of the orthodonci treatment
intervention type: Device
intervention name: .014" NiTi heat-activated archwire
description: .014" NiTi heat-activated archwire In the lower arch during the first three months of the orthodonci treatment
arm group label: Heat-activated archwire
intervention type: Device
intervention name: .014" NiTi Superelastic archwire
description: .014" NiTi superelastic archwireIn the lower arch during the first three months of the orthodonci treatment
arm group label: superelasticwire
criteria: 
gender: All
minimum age: 13 Years
maximum age: 25 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Sonia Plaza, Ms.
role: Study Director
affiliation: Fundación Universitaria CIEO
last name: Suly Amaya, DDS
phone: 315 783 72 45
email: sulyamgo@yahoo.es
last name: Humberto Guzman, DDS
phone: 315 3871090
email: tesisalambres@gmail.com
facility: 
status: Recruiting
contact: 
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country: Colombia
responsible party type: Principal Investigator
investigator affiliation: Fundación Universitaria CIEO
investigator full name: Suly Amaya
investigator title: Teacher Orthodontic department
sharing ipd: No