xml: <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/NCT06020040</url>
    </required_header>
    <id_info>
      <org_study_id>DHZhejiangU-2022（061）</org_study_id>
      <nct_id>NCT06020040</nct_id>
    </id_info>
    <brief_title>Bone Particles Sizes and the Stability of Soft and Hard Tissue in Aesthetic Area</brief_title>
    <official_title>The Relationship Between Bone Particles Sizes and the Stability of Soft and Hard Tissue in Aesthetic Area ：3-year Prospective Intervention Clinical Study</official_title>
    <sponsors>
      <lead_sponsor>
        <agency>The Dental Hospital of Zhejiang University School of Medicine</agency>
        <agency_class>Other</agency_class>
      </lead_sponsor>
    </sponsors>
    <source>The Dental Hospital of Zhejiang University School of Medicine</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>
        After implant restoration, the surrounding tissue, including the gingiva and alveolar bone,&#xD;
        will inevitably reconstruct. The study found that gingival recession was easy to occur in the&#xD;
        aesthetic area of upper anterior teeth within 1 year after implantation, which was mainly due&#xD;
        to the absorption of labial alveolar bone. In order to avoid absorption, the thickness of the&#xD;
        labial bone plate should not be less than 2mm, which is difficult to achieve in the anterior&#xD;
        tooth area. Therefore, guided bone regeneration (GBR) should be performed in the implant&#xD;
        area, which can provide more than 5mm bone increment in the vertical and horizontal positions&#xD;
        with long-term stability, being beneficial for the maintenance of the buccal contour and the&#xD;
        stability of the soft and hard tissues in the aesthetic area.&#xD;
  &#xD;
        In this study, the inorganic bone matrix extracted from bovine bone (Geistlich, Gegreen,&#xD;
        Haiao, etc.) was used for GBR in the area with insufficient bone volume in the anterior&#xD;
        dental implant area. The commercially available xenogeneic bone graft substitutes can be&#xD;
        divided into large particles (1-2mm) and small particles (0.25-1mm) according to the particle&#xD;
        size. Previous studies have found that in 6 months after implantation, the change of vertical&#xD;
        bone height around the implant (i.e. the height from the top of alveolar ridge to the&#xD;
        shoulder of the implant) is related to the particle size of bone powder, and large particles&#xD;
        of bone powder may have better performance in maintaining the vertical bone height due to the&#xD;
        following reasons:&#xD;
  &#xD;
          1. Large bone particles may show better mechanical properties and better mechanical&#xD;
             compression resistance.&#xD;
  &#xD;
          2. Large bone particles may show more reasonable pore size and porosity, which may provide&#xD;
             better environment for the growth of new bone.&#xD;
  &#xD;
          3. Large bone particles may achieve more reasonable and balanced bone remodeling. However,&#xD;
             the effect of bone particle sizes on the maintenance of soft and hard tissue around the&#xD;
             bone graft area is still inconclusive. Thus, the purpose of this study is to compare the&#xD;
             effects of large and small bone particle sizes on the stability of soft and hard tissues&#xD;
             around the bone graft area within 3 years after implant restoration in the anterior&#xD;
             tooth area.&#xD;
      </textblock>
    </brief_summary>
    <detailed_description>
      <textblock>
        Research Purpose: To compare the effects of large and small bone particle sizes on the&#xD;
        stability of soft and hard tissues around the GBR area within 3 years in the esthetics area&#xD;
        of anterior tooth.&#xD;
  &#xD;
        Research Design and Methods:&#xD;
  &#xD;
          1. Type of study design: prospective intervention single-center randomized clinical trial.&#xD;
  &#xD;
          2. Study period: 3 years, from the date of ethics approval to December 2025.&#xD;
  &#xD;
          3. This study takes a single-blind method. During research process, the researchers can't&#xD;
             avoid knowing the type of abutment used by the subjects during the clinical examination&#xD;
             and operation, so the subjects can only be single-blinded.&#xD;
  &#xD;
          4. Measures to control bias:&#xD;
  &#xD;
        1) Selection bias control: the random number table method was used for grouping, and the&#xD;
        blind method was strictly followed in the research process. During the recruiting period,&#xD;
        researchers need to be fully informed of the subjects to improve their understanding and&#xD;
        compliance with the test. At least two or more contact information should be left in case of&#xD;
        minimizing the missed follow-up, and we can contact the subjects in emergency.&#xD;
  &#xD;
        2) Control of information bias: rigorous design of case report form, setting up two&#xD;
        researchers to collect data independently and try to collect the data of objective&#xD;
        indicators, conduct regular researcher training and unify the evaluation criteria.&#xD;
  &#xD;
        3) Confounding bias control: improve the research design, control the grouping of single&#xD;
        variables, and adopt reasonable statistical analysis methods.&#xD;
  &#xD;
        5. When recruit subjects, we will strictly follow the exclusion and inclusion criteria. When&#xD;
        subject who meets the following withdrawal criteria, we will terminate the experiment :&#xD;
  &#xD;
          1. Implant complications during the study, including but not limited to peri-implantitis&#xD;
             and implant fracture, which resulting in implant failure&#xD;
  &#xD;
          2. Subjects with poor compliance, unable to review regularly, and do not pay attention to&#xD;
             oral hygiene maintenance in daily life&#xD;
  &#xD;
          3. Subjects voluntarily asked to withdraw from the study&#xD;
  &#xD;
        6. Design plan and specific arrangements: Subjects are expected to participate in clinical&#xD;
        trials for 3 years, and need to complete follow-up. Complete preoperative examinations and&#xD;
        records will be carried out before surgery, such as gender, age, implant position, smoking,&#xD;
        gingival biotype, keratinized gingival width and so on. Imaging examinations, including&#xD;
        parallel projection X-rays and CBCT, are required on the day of surgery, 6 months after&#xD;
        surgery, 1 year，2 years and 3 years after implant restoration. Gingival tissue information&#xD;
        collection (such as mesial and distal gingival papilla, soft tissue color, texture, level and&#xD;
        contour, and alveolar ridge) on the day of completion of implant restoration, and 1-year, 2&#xD;
        years and 3 years after implant restoration for Pink Esthetic Score (PES) .&#xD;
  &#xD;
        7. Trial suspension criteria: According to the clinical trial protocol:&#xD;
  &#xD;
          1. Controllable adverse events occur, or safety problems are found, which can be reasonably&#xD;
             controlled by improving the research design or means. Suspend and adjust clinical trial&#xD;
             protocols in a timely manner.&#xD;
  &#xD;
          2. Some subjects could not avoid the influence of specific risks, so the trial was&#xD;
             suspended in time and susceptible subjects were excluded.&#xD;
  &#xD;
          3. The data obtained are extremely statistically significant. Apply for an interim&#xD;
             analysis.&#xD;
  &#xD;
        8. Criteria for termination of the trial:&#xD;
  &#xD;
          1. There are serious adverse events, and the adverse events are likely to be related to the&#xD;
             intervention in the trial.&#xD;
  &#xD;
          2. External information (such as other high-quality research or evidence) proves that the&#xD;
             intervention is ineffective or effective, and the current clinical trial is not&#xD;
             necessary to continue.&#xD;
  &#xD;
          3. According to the planned interim analysis to achieve the expected difference in&#xD;
             efficacy, if it has been observed that the intervention program of the experimental&#xD;
             group is significantly better than that of the control group.&#xD;
  &#xD;
        9. The clinical observations, clinical examination values, imaging measurements, and clinical&#xD;
        scale scores generated by the investigator's examination in this study, and original records&#xD;
        were made. The source data record shall indicate the record time, record source and recorder.&#xD;
  &#xD;
        10. Sample size calculation: In this study, subjects will be randomly divided into two groups&#xD;
        (large bone particles or small bone particles) through a table of random numbers. The sample&#xD;
        size of this study is estimated by G*Power software. To satisfy statistical significance, set&#xD;
        the conditions as t tests, α=0.05, 1-β=0.8, ES d=0.8 and the minimum sample size of each&#xD;
        group is calculated to be 21. Based on the standard of 10% loss to follow-up rate, the number&#xD;
        of subjects recruited in each group of this study is set to be 23.&#xD;
  &#xD;
        11. 1) The clinical examination data were measured and averaged by two independent&#xD;
        clinicians, recorded in the case collection form, and analyzed by a third person using spss&#xD;
        19.0 statistical software to evaluate whether there were statistical differences. The imaging&#xD;
        data were called and analyzed by submitting an application to the Affiliated Stomatology&#xD;
        Hospital of Zhejiang University School of Medicine. During the process, the patient's real&#xD;
        name was hidden, and the data quality assurance management was carried out according to the&#xD;
        following requirements: Exclude all missing data, unused data and illogical data.&#xD;
  &#xD;
        2) Screening and sorting out the test data that meet the inclusion criteria, forming a data&#xD;
        set of observational safety and various clinical effects and conducting statistical analysis.&#xD;
  &#xD;
        3) Modification procedure for deviation from the original statistical analysis plan: submit a&#xD;
        deviation report form to the ethics committee. In addition to the deviation statement, the&#xD;
        table shows the frequency of each type of deviation and its impact on the research results.&#xD;
        Behavior is explained and there are actions taken for deviations from the plan.&#xD;
  &#xD;
        4) All records related to the identity of the subjects are kept confidential, and these&#xD;
        materials will not be disclosed to the public outside the scope permitted by relevant laws&#xD;
        and/or regulations.&#xD;
  &#xD;
        12. Statistic analysis: For the collected measurement data, if there is normal distribution&#xD;
        data with roughly equal variance, the parameter method (t-test) is used, otherwise, a&#xD;
        nonparametric test (Mann-Whitney u test) was used. For the collected counting data (the score&#xD;
        of soft tissue around the implant), we used chi-square test.&#xD;
  &#xD;
        13. Informed consent:&#xD;
  &#xD;
          1. This study will be conducted by the research doctor in the Oral Implantation Center of&#xD;
             Zhejiang University Affiliated Stomatology Hospital,and the subjects will be informed&#xD;
             and informed consent will be obtained before surgery.&#xD;
  &#xD;
          2. The informed consent process conforms to the principles of complete notification, full&#xD;
             understanding, and independent choice; the expression of informed consent is easy to&#xD;
             understand and conforms to the level of understanding of the subject group.&#xD;
  &#xD;
          3. This study does not involve vulnerable groups and all subjects will sign the informed&#xD;
             consent form by themselves.&#xD;
  &#xD;
        14. Adverse event reporting:This study did not include measures and interventions other than&#xD;
        routine clinical treatment, and had no other adverse effects on the subjects.&#xD;
  &#xD;
        In the event of an adverse event, we will report it as follows:&#xD;
  &#xD;
          1. Various adverse events: Take timely measures to deal with them and record them in the&#xD;
             case report form.&#xD;
  &#xD;
          2. Serious adverse events (SAE): take measures to deal with them timely, and record in a&#xD;
             case report form, stop the trial at the decision of the investigator, immediately report&#xD;
             to the ethics committee, drug clinical trial institutions and sponsors, and report to&#xD;
             national and provincial food within 24 hours Drug Administration.&#xD;
      </textblock>
    </detailed_description>
    <overall_status>Active, not recruiting</overall_status>
    <start_date type="Actual">May 20, 2023</start_date>
    <completion_date type="Anticipated">December 31, 2027</completion_date>
    <primary_completion_date type="Anticipated">December 31, 2026</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>
      <intervention_model_description>The researchers prospectively and continuously recruited subjects who underwent implant therapy with xenogeneic bone graft material in the Oral Implantation Center of the Stomatology Hospital Affiliated to Zhejiang University School of Medicine, and all subjects who signed written informed consent were divided into 2 groups (large bone particles and small bone particles) through a table of random numbers.</intervention_model_description>
      <primary_purpose>Treatment</primary_purpose>
      <masking>Triple (Participant, Care Provider, Outcomes Assessor)</masking>
      <masking_description>This study takes a single-blind method. During research process, the researchers cannot avoid knowing the type of abutment used by the subjects during the clinical examination and operation, so the subjects can only be single-blinded. The clinical examination data will be measured and averaged by two independent clinicians. The data will be analyzed by a third person.</masking_description>
    </study_design_info>
    <primary_outcome>
      <measure>The change of Vertical facial alveolar bone level (VFBL) from baseline</measure>
      <time_frame>The operation day, 6 months after operation, 1/2/3-year after implant restoration</time_frame>
      <description>The distance from implant shoulder to the highest point of middle facial bone plate</description>
    </primary_outcome>
    <primary_outcome>
      <measure>The change of Pink esthetic score (PES) from baseline</measure>
      <time_frame>The day of completion of implant restoration, 1/2/3-year after implant restoration</time_frame>
      <description>Gingival tissue information collection include mesial and distal gingival papilla, soft tissue color, texture, level and contour, and alveolar ridge. The minimum value is 0, and the maximum value is 14, the higher scores mean a better outcome.</description>
    </primary_outcome>
    <secondary_outcome>
      <measure>The change of horizontal bone thickness from baseline Facial alveolar bone thickness (HFBT)</measure>
      <time_frame>The operation day, 6 months after operation, 1/2/3-year after implant restoration</time_frame>
      <description>Horizontal bone thickness of implant shoulder (HFBT1) and 2mm below the shoulder (HFBT2).</description>
    </secondary_outcome>
    <number_of_arms>2</number_of_arms>
    <enrollment type="Anticipated">46</enrollment>
    <condition>Implant Site Reaction</condition>
    <arm_group>
      <arm_group_label>Large Bone Particles</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>The size of the bone particles that will be used for GBR is 1-2mm.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Small Bone Particles</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>The size of the bone particles that will be used for GBR is 0.25-1mm.</description>
    </arm_group>
    <intervention>
      <intervention_type>Device</intervention_type>
      <intervention_name>Heterograft</intervention_name>
      <description>Heterograft (Geistlich, Gegreen, Heal-All) will be used to repair bone defect in the esthetic area of the anterior teeth with simultaneous implant placement. According to the bone particle size, it can be divided into large bone particles(1-2mm) and small bone particles(0.25-1mm).</description>
      <arm_group_label>Large Bone Particles</arm_group_label>
      <arm_group_label>Small Bone Particles</arm_group_label>
    </intervention>
    <eligibility>
      <criteria>
        <textblock>
          Inclusion Criteria:&#xD;
  &#xD;
            -  1) 18 years old and above&#xD;
  &#xD;
            -  2) Patients with missing maxillary anterior teeth and insufficient horizontal bone&#xD;
               mass of alveolar ridge who indeed need GBR&#xD;
  &#xD;
            -  3) One-wall or two-wall bone defects&#xD;
  &#xD;
            -  4) There is no infection and tooth extraction residue at the implant site&#xD;
  &#xD;
            -  5) Simultaneous implant placement&#xD;
  &#xD;
            -  6) Subjects who voluntarily join the test cohort and sign the informed consent&#xD;
  &#xD;
          Exclusion Criteria:&#xD;
  &#xD;
            -  1) Severe periodontitis or uncontrolled periodontitis&#xD;
  &#xD;
            -  2) History of head and neck radiotherapy&#xD;
  &#xD;
            -  3) History of bisphosphonate administration and injection&#xD;
  &#xD;
            -  4) Uncontrolled severe systemic diseases&#xD;
  &#xD;
            -  5) Patients with heavy smoking&#xD;
  &#xD;
            -  6) Onlay bone graft is needed for bone resorption&#xD;
  &#xD;
            -  7) Three-wall or four-wall bone defects&#xD;
        </textblock>
      </criteria>
      <gender>All</gender>
      <minimum_age>18 Years</minimum_age>
      <maximum_age>70 Years</maximum_age>
      <healthy_volunteers>No</healthy_volunteers>
    </eligibility>
    <overall_official>
      <last_name>Li Weida</last_name>
      <role>Principal Investigator</role>
      <affiliation>Stomatological Hospital Affiliated to Zhejiang University School of Medicine</affiliation>
    </overall_official>
    <location>
      <facility>
        <name>The Stomatologic Hospital, School of Medicine, Zhejiang University</name>
        <address>
          <city>Hangzhou</city>
          <state>Zhejiang</state>
          <zip>310003</zip>
          <country>China</country>
        </address>
      </facility>
    </location>
    <location_countries>
      <country>China</country>
    </location_countries>
    <reference>
      <citation>Zhou Y, Gao J, Sheng M, Qi W, Jin J, He F. Facial alveolar bone alterations and gray value changes based on cone beam computed tomography around maxillary anterior implants: A clinical retrospective study of 1-3 years. Clin Oral Implants Res. 2020 May;31(5):476-487. doi: 10.1111/clr.13583. Epub 2020 Feb 12.</citation>
      <PMID>31990412</PMID>
    </reference>
    <reference>
      <citation>Kheur MG, Kheur S, Lakha T, Jambhekar S, Le B, Jain V. Does Graft Particle Type and Size Affect Ridge Dimensional Changes After Alveolar Ridge Split Procedure? J Oral Maxillofac Surg. 2018 Apr;76(4):761-769. doi: 10.1016/j.joms.2017.11.002. Epub 2017 Dec 2.</citation>
      <PMID>29202263</PMID>
    </reference>
    <verification_date>August 2023</verification_date>
    <study_first_submitted>May 17, 2022</study_first_submitted>
    <study_first_submitted_qc>August 27, 2023</study_first_submitted_qc>
    <study_first_posted type="Actual">August 31, 2023</study_first_posted>
    <last_update_submitted>August 27, 2023</last_update_submitted>
    <last_update_submitted_qc>August 27, 2023</last_update_submitted_qc>
    <last_update_posted type="Actual">August 31, 2023</last_update_posted>
    <responsible_party>
      <responsible_party_type>Sponsor</responsible_party_type>
    </responsible_party>
    <patient_data>
      <sharing_ipd>No</sharing_ipd>
    </patient_data>
    <!-- Results have not yet been posted for this study                                          -->
  </clinical_study>
  
  
text: 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/NCT06020040
  org study id: DHZhejiangU-2022（061）
  nct id: NCT06020040
  lead sponsor: 
  has dmc: No
  is fda regulated drug: No
  is fda regulated device: No
  After implant restoration, the surrounding tissue, including the gingiva and alveolar bone,
        will inevitably reconstruct. The study found that gingival recession was easy to occur in the
        aesthetic area of upper anterior teeth within 1 year after implantation, which was mainly due
        to the absorption of labial alveolar bone. In order to avoid absorption, the thickness of the
        labial bone plate should not be less than 2mm, which is difficult to achieve in the anterior
        tooth area. Therefore, guided bone regeneration (GBR) should be performed in the implant
        area, which can provide more than 5mm bone increment in the vertical and horizontal positions
        with long-term stability, being beneficial for the maintenance of the buccal contour and the
        stability of the soft and hard tissues in the aesthetic area.
  
        In this study, the inorganic bone matrix extracted from bovine bone (Geistlich, Gegreen,
        Haiao, etc.) was used for GBR in the area with insufficient bone volume in the anterior
        dental implant area. The commercially available xenogeneic bone graft substitutes can be
        divided into large particles (1-2mm) and small particles (0.25-1mm) according to the particle
        size. Previous studies have found that in 6 months after implantation, the change of vertical
        bone height around the implant (i.e. the height from the top of alveolar ridge to the
        shoulder of the implant) is related to the particle size of bone powder, and large particles
        of bone powder may have better performance in maintaining the vertical bone height due to the
        following reasons:
  
          1. Large bone particles may show better mechanical properties and better mechanical
             compression resistance.
  
          2. Large bone particles may show more reasonable pore size and porosity, which may provide
             better environment for the growth of new bone.
  
          3. Large bone particles may achieve more reasonable and balanced bone remodeling. However,
             the effect of bone particle sizes on the maintenance of soft and hard tissue around the
             bone graft area is still inconclusive. Thus, the purpose of this study is to compare the
             effects of large and small bone particle sizes on the stability of soft and hard tissues
             around the bone graft area within 3 years after implant restoration in the anterior
             tooth area.
  Research Purpose: To compare the effects of large and small bone particle sizes on the
        stability of soft and hard tissues around the GBR area within 3 years in the esthetics area
        of anterior tooth.
  
        Research Design and Methods:
  
          1. Type of study design: prospective intervention single-center randomized clinical trial.
  
          2. Study period: 3 years, from the date of ethics approval to December 2025.
  
          3. This study takes a single-blind method. During research process, the researchers can't
             avoid knowing the type of abutment used by the subjects during the clinical examination
             and operation, so the subjects can only be single-blinded.
  
          4. Measures to control bias:
  
        1) Selection bias control: the random number table method was used for grouping, and the
        blind method was strictly followed in the research process. During the recruiting period,
        researchers need to be fully informed of the subjects to improve their understanding and
        compliance with the test. At least two or more contact information should be left in case of
        minimizing the missed follow-up, and we can contact the subjects in emergency.
  
        2) Control of information bias: rigorous design of case report form, setting up two
        researchers to collect data independently and try to collect the data of objective
        indicators, conduct regular researcher training and unify the evaluation criteria.
  
        3) Confounding bias control: improve the research design, control the grouping of single
        variables, and adopt reasonable statistical analysis methods.
  
        5. When recruit subjects, we will strictly follow the exclusion and inclusion criteria. When
        subject who meets the following withdrawal criteria, we will terminate the experiment :
  
          1. Implant complications during the study, including but not limited to peri-implantitis
             and implant fracture, which resulting in implant failure
  
          2. Subjects with poor compliance, unable to review regularly, and do not pay attention to
             oral hygiene maintenance in daily life
  
          3. Subjects voluntarily asked to withdraw from the study
  
        6. Design plan and specific arrangements: Subjects are expected to participate in clinical
        trials for 3 years, and need to complete follow-up. Complete preoperative examinations and
        records will be carried out before surgery, such as gender, age, implant position, smoking,
        gingival biotype, keratinized gingival width and so on. Imaging examinations, including
        parallel projection X-rays and CBCT, are required on the day of surgery, 6 months after
        surgery, 1 year，2 years and 3 years after implant restoration. Gingival tissue information
        collection (such as mesial and distal gingival papilla, soft tissue color, texture, level and
        contour, and alveolar ridge) on the day of completion of implant restoration, and 1-year, 2
        years and 3 years after implant restoration for Pink Esthetic Score (PES) .
  
        7. Trial suspension criteria: According to the clinical trial protocol:
  
          1. Controllable adverse events occur, or safety problems are found, which can be reasonably
             controlled by improving the research design or means. Suspend and adjust clinical trial
             protocols in a timely manner.
  
          2. Some subjects could not avoid the influence of specific risks, so the trial was
             suspended in time and susceptible subjects were excluded.
  
          3. The data obtained are extremely statistically significant. Apply for an interim
             analysis.
  
        8. Criteria for termination of the trial:
  
          1. There are serious adverse events, and the adverse events are likely to be related to the
             intervention in the trial.
  
          2. External information (such as other high-quality research or evidence) proves that the
             intervention is ineffective or effective, and the current clinical trial is not
             necessary to continue.
  
          3. According to the planned interim analysis to achieve the expected difference in
             efficacy, if it has been observed that the intervention program of the experimental
             group is significantly better than that of the control group.
  
        9. The clinical observations, clinical examination values, imaging measurements, and clinical
        scale scores generated by the investigator's examination in this study, and original records
        were made. The source data record shall indicate the record time, record source and recorder.
  
        10. Sample size calculation: In this study, subjects will be randomly divided into two groups
        (large bone particles or small bone particles) through a table of random numbers. The sample
        size of this study is estimated by G*Power software. To satisfy statistical significance, set
        the conditions as t tests, α=0.05, 1-β=0.8, ES d=0.8 and the minimum sample size of each
        group is calculated to be 21. Based on the standard of 10% loss to follow-up rate, the number
        of subjects recruited in each group of this study is set to be 23.
  
        11. 1) The clinical examination data were measured and averaged by two independent
        clinicians, recorded in the case collection form, and analyzed by a third person using spss
        19.0 statistical software to evaluate whether there were statistical differences. The imaging
        data were called and analyzed by submitting an application to the Affiliated Stomatology
        Hospital of Zhejiang University School of Medicine. During the process, the patient's real
        name was hidden, and the data quality assurance management was carried out according to the
        following requirements: Exclude all missing data, unused data and illogical data.
  
        2) Screening and sorting out the test data that meet the inclusion criteria, forming a data
        set of observational safety and various clinical effects and conducting statistical analysis.
  
        3) Modification procedure for deviation from the original statistical analysis plan: submit a
        deviation report form to the ethics committee. In addition to the deviation statement, the
        table shows the frequency of each type of deviation and its impact on the research results.
        Behavior is explained and there are actions taken for deviations from the plan.
  
        4) All records related to the identity of the subjects are kept confidential, and these
        materials will not be disclosed to the public outside the scope permitted by relevant laws
        and/or regulations.
  
        12. Statistic analysis: For the collected measurement data, if there is normal distribution
        data with roughly equal variance, the parameter method (t-test) is used, otherwise, a
        nonparametric test (Mann-Whitney u test) was used. For the collected counting data (the score
        of soft tissue around the implant), we used chi-square test.
  
        13. Informed consent:
  
          1. This study will be conducted by the research doctor in the Oral Implantation Center of
             Zhejiang University Affiliated Stomatology Hospital,and the subjects will be informed
             and informed consent will be obtained before surgery.
  
          2. The informed consent process conforms to the principles of complete notification, full
             understanding, and independent choice; the expression of informed consent is easy to
             understand and conforms to the level of understanding of the subject group.
  
          3. This study does not involve vulnerable groups and all subjects will sign the informed
             consent form by themselves.
  
        14. Adverse event reporting:This study did not include measures and interventions other than
        routine clinical treatment, and had no other adverse effects on the subjects.
  
        In the event of an adverse event, we will report it as follows:
  
          1. Various adverse events: Take timely measures to deal with them and record them in the
             case report form.
  
          2. Serious adverse events (SAE): take measures to deal with them timely, and record in a
             case report form, stop the trial at the decision of the investigator, immediately report
             to the ethics committee, drug clinical trial institutions and sponsors, and report to
             national and provincial food within 24 hours Drug Administration.
  allocation: Randomized
  intervention model: Parallel Assignment
  intervention model description: The researchers prospectively and continuously recruited subjects who underwent implant therapy with xenogeneic bone graft material in the Oral Implantation Center of the Stomatology Hospital Affiliated to Zhejiang University School of Medicine, and all subjects who signed written informed consent were divided into 2 groups (large bone particles and small bone particles) through a table of random numbers.
  primary purpose: Treatment
  masking: Triple (Participant, Care Provider, Outcomes Assessor)
  masking description: This study takes a single-blind method. During research process, the researchers cannot avoid knowing the type of abutment used by the subjects during the clinical examination and operation, so the subjects can only be single-blinded. The clinical examination data will be measured and averaged by two independent clinicians. The data will be analyzed by a third person.
  measure: The change of Vertical facial alveolar bone level (VFBL) from baseline
  time frame: The operation day, 6 months after operation, 1/2/3-year after implant restoration
  description: The distance from implant shoulder to the highest point of middle facial bone plate
  measure: The change of Pink esthetic score (PES) from baseline
  time frame: The day of completion of implant restoration, 1/2/3-year after implant restoration
  description: Gingival tissue information collection include mesial and distal gingival papilla, soft tissue color, texture, level and contour, and alveolar ridge. The minimum value is 0, and the maximum value is 14, the higher scores mean a better outcome.
  measure: The change of horizontal bone thickness from baseline Facial alveolar bone thickness (HFBT)
  time frame: The operation day, 6 months after operation, 1/2/3-year after implant restoration
  description: Horizontal bone thickness of implant shoulder (HFBT1) and 2mm below the shoulder (HFBT2).
  arm group label: Large Bone Particles
  arm group type: Experimental
  description: The size of the bone particles that will be used for GBR is 1-2mm.
  arm group label: Small Bone Particles
  arm group type: Experimental
  description: The size of the bone particles that will be used for GBR is 0.25-1mm.
  intervention type: Device
  intervention name: Heterograft
  description: Heterograft (Geistlich, Gegreen, Heal-All) will be used to repair bone defect in the esthetic area of the anterior teeth with simultaneous implant placement. According to the bone particle size, it can be divided into large bone particles(1-2mm) and small bone particles(0.25-1mm).
  arm group label: Large Bone Particles
  arm group label: Small Bone Particles
  criteria: 
  gender: All
  minimum age: 18 Years
  maximum age: 70 Years
  healthy volunteers: No
  last name: Li Weida
  role: Principal Investigator
  affiliation: Stomatological Hospital Affiliated to Zhejiang University School of Medicine
  facility: 
  country: China
  citation: Zhou Y, Gao J, Sheng M, Qi W, Jin J, He F. Facial alveolar bone alterations and gray value changes based on cone beam computed tomography around maxillary anterior implants: A clinical retrospective study of 1-3 years. Clin Oral Implants Res. 2020 May;31(5):476-487. doi: 10.1111/clr.13583. Epub 2020 Feb 12.
  PMID: 31990412
  citation: Kheur MG, Kheur S, Lakha T, Jambhekar S, Le B, Jain V. Does Graft Particle Type and Size Affect Ridge Dimensional Changes After Alveolar Ridge Split Procedure? J Oral Maxillofac Surg. 2018 Apr;76(4):761-769. doi: 10.1016/j.joms.2017.11.002. Epub 2017 Dec 2.
  PMID: 29202263
  responsible party type: Sponsor
  sharing ipd: No