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/NCT05978115</url>
    </required_header>
    <id_info>
      <org_study_id>A01020822</org_study_id>
      <nct_id>NCT05978115</nct_id>
    </id_info>
    <brief_title>Clinical and Radiographic Evaluation of Three Different Modalities for Management of Distal Extension Atrophied Mandibular Ridge: A One Year Prospective Study</brief_title>
    <official_title>Clinical and Radiographic Evaluation of Three Different Modalities for Management of Distal Extension Atrophied Mandibular Ridge: A One Year Prospective Study</official_title>
    <sponsors>
      <lead_sponsor>
        <agency>Mansoura University</agency>
        <agency_class>Other</agency_class>
      </lead_sponsor>
    </sponsors>
    <source>Mansoura University</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>
        Nine patients selected for this study with mandibular free end saddle and atrophied posterior&#xD;
        ridge according to treatment options all patients will be divided randomly into 3 groups:&#xD;
  &#xD;
          -  Group A: included three participants who will receive implant retained partial&#xD;
             overdentures&#xD;
  &#xD;
          -  Group B: included three participants who will receive short implants supported fixed&#xD;
             prosthesis&#xD;
  &#xD;
          -  Group C: included three participants who will receive long implant supported fixed&#xD;
             prosthesis after ridge augmentation.&#xD;
  &#xD;
          -  For Group A: Implant retained partial overdenture The implants will be inserted in first&#xD;
             premolar areas and partial overdenture will be connected with implant by locator&#xD;
             attachment.&#xD;
  &#xD;
          -  For Group B: Short implant supported fixed prosthesis The implants will be inserted in&#xD;
             first premolar, second premolar, and first molar areas without any ridge augmentation&#xD;
             and the implant will be connected by fixed prosthesis&#xD;
  &#xD;
          -  For group C: Long implant supported fixed prosthesis after ridge augmentation The&#xD;
             implants will be inserted in first premolar, second premolar, and first molar areas with&#xD;
             ridge augmentation by using Khoury technique17 and the implants will be connected by&#xD;
             fixed prosthesis&#xD;
  &#xD;
          -  Clinical evaluation will be made in terms of:&#xD;
  &#xD;
               -  Gingival Index (GI)&#xD;
  &#xD;
               -  Plaque Index (PI)&#xD;
  &#xD;
               -  Pocket Depth (PD)&#xD;
  &#xD;
               -  Width of Keratinized Mucosa (KM)&#xD;
  &#xD;
               -  Implant Stability (ISQ).&#xD;
  &#xD;
          -  Radiographic evaluation will include mandibular residual ridge resorption using the&#xD;
             proportional area measurements.&#xD;
  &#xD;
        evaluation periods will be performed at time of insertion T(0), 6 months after insertion&#xD;
        T(6), 12 months after insertion T(6)&#xD;
      </textblock>
    </brief_summary>
    <detailed_description>
      <textblock>
        Introduction Long span distal-extension removable partial dentures (RPDs) are associated with&#xD;
        several problems related to their stability, retention, esthetics, and masticatory&#xD;
        efficiency.1,2 The lack of distal dental support in mandibular Kennedy class I distal&#xD;
        extension-RPDs results in transmission of vertical, horizontal, and torsional forces to&#xD;
        supporting tissues during mastication with subsequent adverse changes in both abutment teeth&#xD;
        and edentulous areas. In addition, constant pressure from the denture base gradually causes&#xD;
        ridge resorption under the denture base.3-5 Prosthodontic management of long span distal&#xD;
        extension partially edentulous patients has expanded with the introduction of Osseo&#xD;
        integrated implants.6 The use of implants to support and retain distal extension partial&#xD;
        overdentures has been reported to minimize RPD dislodgement, provide additional retention and&#xD;
        stability, prevent the development of combination syndrome and improve patient satisfaction&#xD;
        in a cost-effective manner.7,8 Moreover, placing bilateral dental implants distal to canine&#xD;
        area of the residual alveolar ridges is becoming a popular treatment choice in case of&#xD;
        limited height of posterior mandibular ridge7,9,10 Such prostheses can be retained to the&#xD;
        implants with different unsplinted anchors such as ball, Locator, and magnetic attachments.1&#xD;
        Although Implant-supported distal extension prosthesis could be an ideal treatment option,&#xD;
        alveolar resorption, lack of sufficient bone volume and proximity to the inferior alveolar&#xD;
        nerve, presenting a difficult clinical situation for positioning endosseous implants. A bone&#xD;
        height of 10-12mm is generally considered to be the minimal amount of bone required to place&#xD;
        implants of ''sufficient'' length, 9-11mm long, which are most likely to generate good&#xD;
        long-term results and to minimize the risk of permanent damage to the alveolar inferior&#xD;
        nerve.11 Often times, however, the amount of residual bone above the mandibular canal is&#xD;
        &lt;10mm, and implant placement is considered at a higher risk of failure.11To address a case of&#xD;
        reduced bone height in the posterior mandible, either ridge augmentation or placement of&#xD;
        short implant could be the proposed approaches.&#xD;
  &#xD;
        The development of bone augmentation procedures has allowed placement of dental implants into&#xD;
        jawbone areas lacking an amount of bone sufficient for standard implant placement.11 While&#xD;
        augmentation procedures can yield favorable outcomes, they can be associated with significant&#xD;
        postoperative morbidity and complications.12 On the other hand, short implants could be a&#xD;
        simpler, cheaper, and faster alternative to augmentation procedures, even if in some&#xD;
        &quot;critical cases&quot; the residual bone crest above the inferior alveolar nerve is only 5-7 mm in&#xD;
        height, and therefore the surgical augmentation treatment is mandatory.11,12 However, it is&#xD;
        commonly perceived that short implants do not have a good long-term prognosis when compared&#xD;
        with longer implants. Although preliminary findings suggest that short implants may be a&#xD;
        better alternative to various bone augmentation procedures, long-term follow-up evaluations&#xD;
        are indicated to draw definitive conclusion.13-15 Implant-supported removable prostheses&#xD;
        improve patients' satisfaction with treatment and quality of life. When canines are the only&#xD;
        present abutments, insertion of the implants distal the canine areas can provide support and&#xD;
        retention, eliminate the use of unesthetic retentive clasps, and prevent unfavorable&#xD;
        horizontal forces that may damage the abutment periodontium. However, some biological and&#xD;
        mechanical complications remain. Mechanical complications associated with implant-supported&#xD;
        overdentures are loss of retention of attachment systems, the need to replace retention&#xD;
        elements and to reline or repair the resin portion of the denture, and implant fracture.&#xD;
        Despite their success, implant-supported removable prostheses require periodic maintenance.&#xD;
  &#xD;
        Based on the proceeding, three treatment modalities could be the solution for long span&#xD;
        distal-extension removable partial dentures (RPDs); implant retained partial overdenture,&#xD;
        short implant supported fixed prosthesis, and long implant supported fixed prosthesis after&#xD;
        ridge augmentation. Comparing the clinical and radiographic outcomes of the three different&#xD;
        treatment modalities are relatively scarce in literature to explore which treatment is more&#xD;
        appropriate regarding periodontal tissue health and patient satisfaction.&#xD;
  &#xD;
        Aim of the work This study will aim to assess the clinical and radiographic outcomes of three&#xD;
        different treatments modalities for management of distal extension atrophied mandibular&#xD;
        ridge; A; implant retained partial overdenture, B; short implant supported fixed prosthesis,&#xD;
        C; long implant supported prosthesis after ridge augmentation&#xD;
  &#xD;
          -  Clinical evaluation will be made in terms of:&#xD;
  &#xD;
             • Gingival Index (GI)&#xD;
  &#xD;
             • Plaque Index (PI)&#xD;
  &#xD;
               -  Pocket Depth (PD)&#xD;
  &#xD;
               -  Width of Keratinized Mucosa (KM)&#xD;
  &#xD;
               -  Implant Stability (ISQ).&#xD;
  &#xD;
          -  Radiographic evaluation will include mandibular residual ridge resorption using the&#xD;
             proportional area measurements.&#xD;
  &#xD;
        Materials and Methods&#xD;
  &#xD;
          1. Patient selection and grouping:&#xD;
  &#xD;
        Nine patients aged between (45 to 70 years) will be selected from outpatient clinic of the&#xD;
        Removable Prosthodontic Department, Faculty of Dentistry, Mansoura University, Egypt.&#xD;
  &#xD;
          -  All selected participants will be required to have the following inclusion criteria:&#xD;
  &#xD;
             1. Atrophied partially edentulism in the posterior mandible having a residual bone&#xD;
             height of 6-8mm bone between inferior alveolar nerve and crest of the ridge to receive&#xD;
             implants 2. Residual alveolar ridges covered with healthy mucosa without any signs of&#xD;
             inflammation or remaining roots.&#xD;
  &#xD;
             3. Normal maxilla-mandibular relationship with sufficient available restorative space.16&#xD;
  &#xD;
          -  Patients with the following conditions will be excluded:&#xD;
  &#xD;
               1. Diseases that affect bone metabolism, eg: uncontrolled diabetes,&#xD;
                  hyperparathyroidism, and osteoporosis.&#xD;
  &#xD;
               2. Systemic diseases that may affect osteointegration or complicate surgical&#xD;
                  procedures, eg: liver diseases, heart diseases and radiotherapy in head and neck&#xD;
                  region.&#xD;
  &#xD;
               3. Abnormal or harmful habits eg: smoking, bruxism, and clenching.&#xD;
  &#xD;
               4. Uncooperative patients and patients with poor oral hygiene.&#xD;
  &#xD;
          -  The study protocol will be reviewed and approved by ethical committee of the Faculty of&#xD;
             Dentistry, Mansoura University&#xD;
  &#xD;
          -  Detailed written information about treatment strategy will be provided to all&#xD;
             participants who meet the criteria, and then they will sign an informed consent. After&#xD;
             consent will be given, eligible participants will be randomly divided into three groups:&#xD;
  &#xD;
             1. Group A: included three participants who will receive implant retained partial&#xD;
             overdentures 2. Group B: included three participants who will receive short implants&#xD;
             supported fixed prosthesis 3. Group C: included three participants who will receive long&#xD;
             implant supported fixed prosthesis after ridge augmentation.&#xD;
  &#xD;
             2. Surgical and prosthetic procedures:&#xD;
  &#xD;
          -  Cone Beam Computed Tomography (CBCT) will be performed for each patient to mark implant&#xD;
             placement sites, detect magnification errors, and select proper implant lengths. The&#xD;
             implants will be inserted using non-submerged flapless surgical approach with the same&#xD;
             operator in all groups.&#xD;
  &#xD;
          -  For Group A: Implant retained partial overdenture The implants will be inserted in first&#xD;
             premolar areas and partial overdenture will be connected with implant by locator&#xD;
             attachment.&#xD;
  &#xD;
          -  For Group B: Short implant supported fixed prosthesis The implants will be inserted in&#xD;
             first premolar, second premolar, and first molar areas without any ridge augmentation&#xD;
             and the implant will be connected by fixed prosthesis&#xD;
  &#xD;
          -  For group C: Long implant supported fixed prosthesis after ridge augmentation The&#xD;
             implants will be inserted in first premolar, second premolar, and first molar areas with&#xD;
             ridge augmentation by using Khoury technique17 and the implants will be connected by&#xD;
             fixed prosthesis&#xD;
  &#xD;
             3. Evaluation of peri-implant tissues Clinical and radiographic evaluations of&#xD;
             peri-implant tissues will be performed after definite prosthesis insertion (T0), six&#xD;
             (T6) and twelve (T12) months after insertion.&#xD;
  &#xD;
        A. Clinical evaluation&#xD;
  &#xD;
          -  The parameters for clinical evaluation of peri-implant tissue included: plaque index,&#xD;
             gingival index, pocket depth, thickness of keratinized mucosa, and implant stability.&#xD;
  &#xD;
               1. Gingival index (GI):&#xD;
  &#xD;
                  Modified gingival index will be recorded according to Mombelli et al.18, as&#xD;
                  follows: score 0; normal gingival, score 1; mild inflammation (slight change in&#xD;
                  color &amp; slight edema), but no bleeding on probing, score 2; moderate inflammation&#xD;
                  (redness &amp; edema), and bleeding on probing, and score 3; sever inflammation (marked&#xD;
                  redness, edema &amp; ulceration) with tendency to spontaneous bleeding.&#xD;
  &#xD;
               2. Plaque index (PI):&#xD;
  &#xD;
                  Plaque will be assessed according to modified plaque index describe by Mombelli et&#xD;
                  al.18 as follows: score 0; no plaque detected, score 1; plaque recognized only by&#xD;
                  running a probe across a smooth marginal surface of the implant, score 2; plaque&#xD;
                  can be seen by naked eye, and score 3; abundance of soft mater.&#xD;
  &#xD;
               3. Pocket depth (PD):&#xD;
  &#xD;
                  Using a calibrated plastic periodontal probe, the distance between marginal border&#xD;
                  of the gingiva and the tip of the probe will be measured in mm and considered as&#xD;
                  pocket depth (PD).19&#xD;
  &#xD;
               4. The width of keratinized mucosa (KM):&#xD;
  &#xD;
                  The width of peri-implant keratinized mucosa will be measured in mm using a&#xD;
                  calibrated plastic periodontal probe. Differences in color, texture and mobility&#xD;
                  between the keratinized mucosa and the lining mucosa served as markers for the&#xD;
                  detection of the muco-gingival junction.20 KM was then measured as the distance&#xD;
                  between the gingival margin and the muco-gingival junction.&#xD;
  &#xD;
               5. Implant stability (ISQ):&#xD;
  &#xD;
          -  Implant stability will be assessed using resonance frequency analysis (RFA). The&#xD;
             resonance frequencies will be measured with the osstell® device (implant stability&#xD;
             meter) and expressed with ISQ measurement scale (implant stability quotient). 21,22&#xD;
  &#xD;
        B. Radiographic evaluation:&#xD;
  &#xD;
          -  Radiographic evaluation will be assessed using Cone Beam Computed Tomography (CBCT) and&#xD;
             periapical radiographic X ray.&#xD;
  &#xD;
          -  Implant dimensions in the radiographs will be compared with actual implant dimensions to&#xD;
             detect magnification errors. The ratio between implant dimensions in the radiographs and&#xD;
             actual implant dimensions will be used to modify the apparent measurement of&#xD;
             peri-implant bone levels in the radiographs to obtain their actual values.&#xD;
  &#xD;
          -  Crestal alveolar bone changes will be determined along vertical and horizontal planes as&#xD;
             recommended by Elsyad et al. 19,23&#xD;
  &#xD;
          -  For vertical alveolar bone changes: the distance between implant shoulder (A point) and&#xD;
             first bone to implant contact (B point) called DIB, indicates vertical bone level in mm&#xD;
             (AB line)&#xD;
  &#xD;
          -  For horizontal alveolar bone changes: the distance between the marginal bone level (C&#xD;
             point) [ which represents the intersection point of a tangent to the horizontal bone&#xD;
             crest (CD line) and another tangent to the crater-shaped defect (CB line)] and the&#xD;
             implant perpendicularly: indicates horizontal bone level(mm).&#xD;
  &#xD;
          -  Vertical bone loss (VBL) will be calculated by subtracting DIB at T6 and T12 from DIB at&#xD;
             T0. Horizontal bone loss (HBLO) will be calculated by subtracting HBL at T6 and T12 from&#xD;
             HBL at T0.&#xD;
  &#xD;
          -  Crestal alveolar bone changes (vertical and horizontal bone loss) will be measured at&#xD;
             mesial and distal surface of each implant.&#xD;
  &#xD;
        C. Implant survival To estimate the cumulative survival rate, a Kaplan-Meier analysis will be&#xD;
        used, involving the following clinical parameters for success suggested by Albrektsson and&#xD;
        Isidor 24; no clinical problems (pus, suppuration, implant mobility and pain) and limited&#xD;
        change in peri-implant crestal bone level, as assessed by radiographic follow-up: during the&#xD;
        first year of loading ≤ 1.5 mm and annual additional bone loss thereafter ≤ 0.2 mm/year. An&#xD;
        implant was classified as a 'survived implant' when it was still functioning, irrespective of&#xD;
        its conditions and do not need immediate removal, but did not fulfill the success criteria.&#xD;
      </textblock>
    </detailed_description>
    <overall_status>Active, not recruiting</overall_status>
    <start_date type="Actual">August 20, 2021</start_date>
    <completion_date type="Anticipated">February 1, 2024</completion_date>
    <primary_completion_date type="Actual">November 20, 2022</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>Treatment</primary_purpose>
      <masking>Single (Investigator)</masking>
    </study_design_info>
    <primary_outcome>
      <measure>Gingival Index (GI)</measure>
      <time_frame>at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)</time_frame>
      <description>Modified gingival index will be recorded according to Mombelli et al, as follows: score 0; normal gingival, score 1; mild inflammation (slight change in color &amp; slight edema), but no bleeding on probing, score 2; moderate inflammation (redness &amp; edema), and bleeding on probing, and score 3; sever inflammation (marked redness, edema &amp; ulceration) with tendency to spontaneous bleeding.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Plaque Index (PI)</measure>
      <time_frame>at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)</time_frame>
      <description>Plaque will be assessed according to modified plaque index describe by Mombelli et al. as follows: score 0; no plaque detected, score 1; plaque recognized only by running a probe across a smooth marginal surface of the implant, score 2; plaque can be seen by naked eye, and score 3; abundance of soft mater.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Pocket Depth (PD)</measure>
      <time_frame>at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)</time_frame>
      <description>Using a calibrated plastic periodontal probe, the distance between marginal border of the gingiva and the tip of the probe will be measured in mm and considered as pocket depth (PD).</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Width of Keratinized Mucosa (KM)</measure>
      <time_frame>at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)</time_frame>
      <description>The width of peri-implant keratinized mucosa will be measured in mm using a calibrated plastic periodontal probe. Differences in color, texture and mobility between the keratinized mucosa and the lining mucosa served as markers for the detection of the muco-gingival junction. KM was then measured as the distance between the gingival margin and the muco-gingival junction.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Implant Stability (ISQ)</measure>
      <time_frame>at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)</time_frame>
      <description>Implant stability will be assessed using resonance frequency analysis (RFA). The resonance frequencies will be measured with the osstell® device (implant stability meter) and expressed with ISQ measurement scale (implant stability quotient).</description>
    </primary_outcome>
    <number_of_arms>3</number_of_arms>
    <enrollment type="Actual">9</enrollment>
    <condition>Different Treatment Outcomes of Atrophied Distal Extension Cases</condition>
    <arm_group>
      <arm_group_label>short implant supported removable partial overdenture</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
    </arm_group>
    <arm_group>
      <arm_group_label>short Implant supported fixed partial denture</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
    </arm_group>
    <arm_group>
      <arm_group_label>Ridge Augmentation and implant supported fixed partial denture</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
    </arm_group>
    <intervention>
      <intervention_type>Procedure</intervention_type>
      <intervention_name>implant supported prosthesis</intervention_name>
      <description>Group A: short dental implant placement + Removable partial denture Group B: Short implant placement + Fixed partial denture Group c: Bone Augmentation + Implant placement + Fixed Partial denture</description>
      <arm_group_label>Ridge Augmentation and implant supported fixed partial denture</arm_group_label>
      <arm_group_label>short Implant supported fixed partial denture</arm_group_label>
      <arm_group_label>short implant supported removable partial overdenture</arm_group_label>
      <other_name>Bone augmentation for atrophied ridge</other_name>
    </intervention>
    <eligibility>
      <criteria>
        <textblock>
          Inclusion Criteria:&#xD;
  &#xD;
            -  All selected participants will be required to have the following inclusion criteria:&#xD;
  &#xD;
                 1. Atrophied partially edentulism in the posterior mandible having a residual bone&#xD;
                    height of 6-8mm bone between inferior alveolar nerve and crest of the ridge to&#xD;
                    receive implants&#xD;
  &#xD;
                 2. Residual alveolar ridges covered with healthy mucosa without any signs of&#xD;
                    inflammation or remaining roots.&#xD;
  &#xD;
                 3. Normal maxilla-mandibular relationship with sufficient available restorative&#xD;
                    space.&#xD;
  &#xD;
          Exclusion Criteria:&#xD;
  &#xD;
            -  -Patients with the following conditions will be excluded:&#xD;
  &#xD;
                 1. Diseases that affect bone metabolism, eg: uncontrolled diabetes,&#xD;
                    hyperparathyroidism, and osteoporosis.&#xD;
  &#xD;
                 2. Systemic diseases that may affect osteointegration or complicate surgical&#xD;
                    procedures, eg: liver diseases, heart diseases and radiotherapy in head and neck&#xD;
                    region.&#xD;
  &#xD;
                 3. Abnormal or harmful habits eg: smoking, bruxism, and clenching.&#xD;
  &#xD;
                 4. Uncooperative patients and patients with poor oral hygiene.&#xD;
        </textblock>
      </criteria>
      <gender>Male</gender>
      <minimum_age>50 Years</minimum_age>
      <maximum_age>70 Years</maximum_age>
      <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
    </eligibility>
    <overall_official>
      <last_name>Mohamed Shady, MD</last_name>
      <role>Principal Investigator</role>
      <affiliation>Mansoura University Faculty of Dentistry, Prosthodontics department</affiliation>
    </overall_official>
    <location>
      <facility>
        <name>Mansoura University, Faculty of dentistry</name>
        <address>
          <city>Mansoura</city>
          <country>Egypt</country>
        </address>
      </facility>
    </location>
    <location_countries>
      <country>Egypt</country>
    </location_countries>
    <verification_date>July 2023</verification_date>
    <study_first_submitted>July 28, 2023</study_first_submitted>
    <study_first_submitted_qc>July 28, 2023</study_first_submitted_qc>
    <study_first_posted type="Actual">August 7, 2023</study_first_posted>
    <last_update_submitted>July 28, 2023</last_update_submitted>
    <last_update_submitted_qc>July 28, 2023</last_update_submitted_qc>
    <last_update_posted type="Actual">August 7, 2023</last_update_posted>
    <responsible_party>
      <responsible_party_type>Principal Investigator</responsible_party_type>
      <investigator_affiliation>Mansoura University</investigator_affiliation>
      <investigator_full_name>Mohamed shady</investigator_full_name>
      <investigator_title>Assistant Professor</investigator_title>
    </responsible_party>
    <condition_browse>
      <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
      <mesh_term>Atrophy</mesh_term>
    </condition_browse>
    <!-- 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/NCT05978115
  org study id: A01020822
  nct id: NCT05978115
  lead sponsor: 
  has dmc: No
  is fda regulated drug: No
  is fda regulated device: No
  Nine patients selected for this study with mandibular free end saddle and atrophied posterior
        ridge according to treatment options all patients will be divided randomly into 3 groups:
  
          -  Group A: included three participants who will receive implant retained partial
             overdentures
  
          -  Group B: included three participants who will receive short implants supported fixed
             prosthesis
  
          -  Group C: included three participants who will receive long implant supported fixed
             prosthesis after ridge augmentation.
  
          -  For Group A: Implant retained partial overdenture The implants will be inserted in first
             premolar areas and partial overdenture will be connected with implant by locator
             attachment.
  
          -  For Group B: Short implant supported fixed prosthesis The implants will be inserted in
             first premolar, second premolar, and first molar areas without any ridge augmentation
             and the implant will be connected by fixed prosthesis
  
          -  For group C: Long implant supported fixed prosthesis after ridge augmentation The
             implants will be inserted in first premolar, second premolar, and first molar areas with
             ridge augmentation by using Khoury technique17 and the implants will be connected by
             fixed prosthesis
  
          -  Clinical evaluation will be made in terms of:
  
               -  Gingival Index (GI)
  
               -  Plaque Index (PI)
  
               -  Pocket Depth (PD)
  
               -  Width of Keratinized Mucosa (KM)
  
               -  Implant Stability (ISQ).
  
          -  Radiographic evaluation will include mandibular residual ridge resorption using the
             proportional area measurements.
  
        evaluation periods will be performed at time of insertion T(0), 6 months after insertion
        T(6), 12 months after insertion T(6)
  Introduction Long span distal-extension removable partial dentures (RPDs) are associated with
        several problems related to their stability, retention, esthetics, and masticatory
        efficiency.1,2 The lack of distal dental support in mandibular Kennedy class I distal
        extension-RPDs results in transmission of vertical, horizontal, and torsional forces to
        supporting tissues during mastication with subsequent adverse changes in both abutment teeth
        and edentulous areas. In addition, constant pressure from the denture base gradually causes
        ridge resorption under the denture base.3-5 Prosthodontic management of long span distal
        extension partially edentulous patients has expanded with the introduction of Osseo
        integrated implants.6 The use of implants to support and retain distal extension partial
        overdentures has been reported to minimize RPD dislodgement, provide additional retention and
        stability, prevent the development of combination syndrome and improve patient satisfaction
        in a cost-effective manner.7,8 Moreover, placing bilateral dental implants distal to canine
        area of the residual alveolar ridges is becoming a popular treatment choice in case of
        limited height of posterior mandibular ridge7,9,10 Such prostheses can be retained to the
        implants with different unsplinted anchors such as ball, Locator, and magnetic attachments.1
        Although Implant-supported distal extension prosthesis could be an ideal treatment option,
        alveolar resorption, lack of sufficient bone volume and proximity to the inferior alveolar
        nerve, presenting a difficult clinical situation for positioning endosseous implants. A bone
        height of 10-12mm is generally considered to be the minimal amount of bone required to place
        implants of ''sufficient'' length, 9-11mm long, which are most likely to generate good
        long-term results and to minimize the risk of permanent damage to the alveolar inferior
        nerve.11 Often times, however, the amount of residual bone above the mandibular canal is
        <10mm, and implant placement is considered at a higher risk of failure.11To address a case of
        reduced bone height in the posterior mandible, either ridge augmentation or placement of
        short implant could be the proposed approaches.
  
        The development of bone augmentation procedures has allowed placement of dental implants into
        jawbone areas lacking an amount of bone sufficient for standard implant placement.11 While
        augmentation procedures can yield favorable outcomes, they can be associated with significant
        postoperative morbidity and complications.12 On the other hand, short implants could be a
        simpler, cheaper, and faster alternative to augmentation procedures, even if in some
        "critical cases" the residual bone crest above the inferior alveolar nerve is only 5-7 mm in
        height, and therefore the surgical augmentation treatment is mandatory.11,12 However, it is
        commonly perceived that short implants do not have a good long-term prognosis when compared
        with longer implants. Although preliminary findings suggest that short implants may be a
        better alternative to various bone augmentation procedures, long-term follow-up evaluations
        are indicated to draw definitive conclusion.13-15 Implant-supported removable prostheses
        improve patients' satisfaction with treatment and quality of life. When canines are the only
        present abutments, insertion of the implants distal the canine areas can provide support and
        retention, eliminate the use of unesthetic retentive clasps, and prevent unfavorable
        horizontal forces that may damage the abutment periodontium. However, some biological and
        mechanical complications remain. Mechanical complications associated with implant-supported
        overdentures are loss of retention of attachment systems, the need to replace retention
        elements and to reline or repair the resin portion of the denture, and implant fracture.
        Despite their success, implant-supported removable prostheses require periodic maintenance.
  
        Based on the proceeding, three treatment modalities could be the solution for long span
        distal-extension removable partial dentures (RPDs); implant retained partial overdenture,
        short implant supported fixed prosthesis, and long implant supported fixed prosthesis after
        ridge augmentation. Comparing the clinical and radiographic outcomes of the three different
        treatment modalities are relatively scarce in literature to explore which treatment is more
        appropriate regarding periodontal tissue health and patient satisfaction.
  
        Aim of the work This study will aim to assess the clinical and radiographic outcomes of three
        different treatments modalities for management of distal extension atrophied mandibular
        ridge; A; implant retained partial overdenture, B; short implant supported fixed prosthesis,
        C; long implant supported prosthesis after ridge augmentation
  
          -  Clinical evaluation will be made in terms of:
  
             • Gingival Index (GI)
  
             • Plaque Index (PI)
  
               -  Pocket Depth (PD)
  
               -  Width of Keratinized Mucosa (KM)
  
               -  Implant Stability (ISQ).
  
          -  Radiographic evaluation will include mandibular residual ridge resorption using the
             proportional area measurements.
  
        Materials and Methods
  
          1. Patient selection and grouping:
  
        Nine patients aged between (45 to 70 years) will be selected from outpatient clinic of the
        Removable Prosthodontic Department, Faculty of Dentistry, Mansoura University, Egypt.
  
          -  All selected participants will be required to have the following inclusion criteria:
  
             1. Atrophied partially edentulism in the posterior mandible having a residual bone
             height of 6-8mm bone between inferior alveolar nerve and crest of the ridge to receive
             implants 2. Residual alveolar ridges covered with healthy mucosa without any signs of
             inflammation or remaining roots.
  
             3. Normal maxilla-mandibular relationship with sufficient available restorative space.16
  
          -  Patients with the following conditions will be excluded:
  
               1. Diseases that affect bone metabolism, eg: uncontrolled diabetes,
                  hyperparathyroidism, and osteoporosis.
  
               2. Systemic diseases that may affect osteointegration or complicate surgical
                  procedures, eg: liver diseases, heart diseases and radiotherapy in head and neck
                  region.
  
               3. Abnormal or harmful habits eg: smoking, bruxism, and clenching.
  
               4. Uncooperative patients and patients with poor oral hygiene.
  
          -  The study protocol will be reviewed and approved by ethical committee of the Faculty of
             Dentistry, Mansoura University
  
          -  Detailed written information about treatment strategy will be provided to all
             participants who meet the criteria, and then they will sign an informed consent. After
             consent will be given, eligible participants will be randomly divided into three groups:
  
             1. Group A: included three participants who will receive implant retained partial
             overdentures 2. Group B: included three participants who will receive short implants
             supported fixed prosthesis 3. Group C: included three participants who will receive long
             implant supported fixed prosthesis after ridge augmentation.
  
             2. Surgical and prosthetic procedures:
  
          -  Cone Beam Computed Tomography (CBCT) will be performed for each patient to mark implant
             placement sites, detect magnification errors, and select proper implant lengths. The
             implants will be inserted using non-submerged flapless surgical approach with the same
             operator in all groups.
  
          -  For Group A: Implant retained partial overdenture The implants will be inserted in first
             premolar areas and partial overdenture will be connected with implant by locator
             attachment.
  
          -  For Group B: Short implant supported fixed prosthesis The implants will be inserted in
             first premolar, second premolar, and first molar areas without any ridge augmentation
             and the implant will be connected by fixed prosthesis
  
          -  For group C: Long implant supported fixed prosthesis after ridge augmentation The
             implants will be inserted in first premolar, second premolar, and first molar areas with
             ridge augmentation by using Khoury technique17 and the implants will be connected by
             fixed prosthesis
  
             3. Evaluation of peri-implant tissues Clinical and radiographic evaluations of
             peri-implant tissues will be performed after definite prosthesis insertion (T0), six
             (T6) and twelve (T12) months after insertion.
  
        A. Clinical evaluation
  
          -  The parameters for clinical evaluation of peri-implant tissue included: plaque index,
             gingival index, pocket depth, thickness of keratinized mucosa, and implant stability.
  
               1. Gingival index (GI):
  
                  Modified gingival index will be recorded according to Mombelli et al.18, as
                  follows: score 0; normal gingival, score 1; mild inflammation (slight change in
                  color & slight edema), but no bleeding on probing, score 2; moderate inflammation
                  (redness & edema), and bleeding on probing, and score 3; sever inflammation (marked
                  redness, edema & ulceration) with tendency to spontaneous bleeding.
  
               2. Plaque index (PI):
  
                  Plaque will be assessed according to modified plaque index describe by Mombelli et
                  al.18 as follows: score 0; no plaque detected, score 1; plaque recognized only by
                  running a probe across a smooth marginal surface of the implant, score 2; plaque
                  can be seen by naked eye, and score 3; abundance of soft mater.
  
               3. Pocket depth (PD):
  
                  Using a calibrated plastic periodontal probe, the distance between marginal border
                  of the gingiva and the tip of the probe will be measured in mm and considered as
                  pocket depth (PD).19
  
               4. The width of keratinized mucosa (KM):
  
                  The width of peri-implant keratinized mucosa will be measured in mm using a
                  calibrated plastic periodontal probe. Differences in color, texture and mobility
                  between the keratinized mucosa and the lining mucosa served as markers for the
                  detection of the muco-gingival junction.20 KM was then measured as the distance
                  between the gingival margin and the muco-gingival junction.
  
               5. Implant stability (ISQ):
  
          -  Implant stability will be assessed using resonance frequency analysis (RFA). The
             resonance frequencies will be measured with the osstell® device (implant stability
             meter) and expressed with ISQ measurement scale (implant stability quotient). 21,22
  
        B. Radiographic evaluation:
  
          -  Radiographic evaluation will be assessed using Cone Beam Computed Tomography (CBCT) and
             periapical radiographic X ray.
  
          -  Implant dimensions in the radiographs will be compared with actual implant dimensions to
             detect magnification errors. The ratio between implant dimensions in the radiographs and
             actual implant dimensions will be used to modify the apparent measurement of
             peri-implant bone levels in the radiographs to obtain their actual values.
  
          -  Crestal alveolar bone changes will be determined along vertical and horizontal planes as
             recommended by Elsyad et al. 19,23
  
          -  For vertical alveolar bone changes: the distance between implant shoulder (A point) and
             first bone to implant contact (B point) called DIB, indicates vertical bone level in mm
             (AB line)
  
          -  For horizontal alveolar bone changes: the distance between the marginal bone level (C
             point) [ which represents the intersection point of a tangent to the horizontal bone
             crest (CD line) and another tangent to the crater-shaped defect (CB line)] and the
             implant perpendicularly: indicates horizontal bone level(mm).
  
          -  Vertical bone loss (VBL) will be calculated by subtracting DIB at T6 and T12 from DIB at
             T0. Horizontal bone loss (HBLO) will be calculated by subtracting HBL at T6 and T12 from
             HBL at T0.
  
          -  Crestal alveolar bone changes (vertical and horizontal bone loss) will be measured at
             mesial and distal surface of each implant.
  
        C. Implant survival To estimate the cumulative survival rate, a Kaplan-Meier analysis will be
        used, involving the following clinical parameters for success suggested by Albrektsson and
        Isidor 24; no clinical problems (pus, suppuration, implant mobility and pain) and limited
        change in peri-implant crestal bone level, as assessed by radiographic follow-up: during the
        first year of loading ≤ 1.5 mm and annual additional bone loss thereafter ≤ 0.2 mm/year. An
        implant was classified as a 'survived implant' when it was still functioning, irrespective of
        its conditions and do not need immediate removal, but did not fulfill the success criteria.
  allocation: Randomized
  intervention model: Parallel Assignment
  primary purpose: Treatment
  masking: Single (Investigator)
  measure: Gingival Index (GI)
  time frame: at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)
  description: Modified gingival index will be recorded according to Mombelli et al, as follows: score 0; normal gingival, score 1; mild inflammation (slight change in color & slight edema), but no bleeding on probing, score 2; moderate inflammation (redness & edema), and bleeding on probing, and score 3; sever inflammation (marked redness, edema & ulceration) with tendency to spontaneous bleeding.
  measure: Plaque Index (PI)
  time frame: at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)
  description: Plaque will be assessed according to modified plaque index describe by Mombelli et al. as follows: score 0; no plaque detected, score 1; plaque recognized only by running a probe across a smooth marginal surface of the implant, score 2; plaque can be seen by naked eye, and score 3; abundance of soft mater.
  measure: Pocket Depth (PD)
  time frame: at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)
  description: Using a calibrated plastic periodontal probe, the distance between marginal border of the gingiva and the tip of the probe will be measured in mm and considered as pocket depth (PD).
  measure: Width of Keratinized Mucosa (KM)
  time frame: at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)
  description: The width of peri-implant keratinized mucosa will be measured in mm using a calibrated plastic periodontal probe. Differences in color, texture and mobility between the keratinized mucosa and the lining mucosa served as markers for the detection of the muco-gingival junction. KM was then measured as the distance between the gingival margin and the muco-gingival junction.
  measure: Implant Stability (ISQ)
  time frame: at time of insertion of prosthesis T(0), 6 months after insertion T(6), 12 months after insertion T(12)
  description: Implant stability will be assessed using resonance frequency analysis (RFA). The resonance frequencies will be measured with the osstell® device (implant stability meter) and expressed with ISQ measurement scale (implant stability quotient).
  arm group label: short implant supported removable partial overdenture
  arm group type: Experimental
  arm group label: short Implant supported fixed partial denture
  arm group type: Experimental
  arm group label: Ridge Augmentation and implant supported fixed partial denture
  arm group type: Experimental
  intervention type: Procedure
  intervention name: implant supported prosthesis
  description: Group A: short dental implant placement + Removable partial denture Group B: Short implant placement + Fixed partial denture Group c: Bone Augmentation + Implant placement + Fixed Partial denture
  arm group label: Ridge Augmentation and implant supported fixed partial denture
  arm group label: short Implant supported fixed partial denture
  arm group label: short implant supported removable partial overdenture
  other name: Bone augmentation for atrophied ridge
  criteria: 
  gender: Male
  minimum age: 50 Years
  maximum age: 70 Years
  healthy volunteers: Accepts Healthy Volunteers
  last name: Mohamed Shady, MD
  role: Principal Investigator
  affiliation: Mansoura University Faculty of Dentistry, Prosthodontics department
  facility: 
  country: Egypt
  responsible party type: Principal Investigator
  investigator affiliation: Mansoura University
  investigator full name: Mohamed shady
  investigator title: Assistant Professor
  mesh term: Atrophy