<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/NCT03242330</url>
  </required_header>
  <id_info>
    <org_study_id>Cairo Uni</org_study_id>
    <nct_id>NCT03242330</nct_id>
  </id_info>
  <brief_title>Two-piece Versus Single-piece Patient-specific Titanium Subperiosteal Implants</brief_title>
  <official_title>Implant Survival in Two-piece Versus Single-piece Patient-specific Titanium Subperiosteal Implants in Atrophied Edentulous Mandibles: Randomized Clinical Trial</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Cairo University</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Cairo University</source>
  <oversight_info>
    <has_dmc>Yes</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>
      The objective of this trial is to find out if there is a difference between single-piece and&#xD;
      two-piece titanium patient-specific mandibular subperiosteal implants in terms of implant&#xD;
      survival, patient satisfaction, and soft tissue dehiscence. This is to enhance both surgical&#xD;
      and prosthetic outcomes for the sake of improved implant longevity, soft tissue health and&#xD;
      patient well-being.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      After obtaining a thorough medical and dental history and performing necessary laboratory&#xD;
      investigations, the following steps will be undertaken:&#xD;
&#xD;
      Preoperative prosthetic preparation:&#xD;
&#xD;
        -  For eligible patients who are already wearing upper and lower complete dentures: The&#xD;
           dentures will be checked for adaptation, fit, stability and occlusion.&#xD;
&#xD;
        -  For eligible patients who are not wearing upper and lower complete dentures:&#xD;
&#xD;
      Preliminary alginate impressions will be made using a perforated stock tray for both the&#xD;
      maxillary and mandibular arches. Impressions are then poured into dental stone to obtain the&#xD;
      diagnostic models. Occlusion blocks will be constructed over the diagnostic models, followed&#xD;
      by bite registration, try-in and delivery of upper and lower complete dentures.&#xD;
&#xD;
      Afterwards, approved complete dentures will be duplicated using laboratory condensation&#xD;
      silicone to construct a radiographic stent. The radiographic stent is prepared by using a&#xD;
      ratio of 3:1 acrylic resin to barium sulphate mixture, and then the patient is sent for a&#xD;
      Cone Beam Computed Tomography (CBCT) scan.&#xD;
&#xD;
      CBCT scanning and virtual design of the patient-specific implant (PSI):&#xD;
&#xD;
      The CBCT scan of the patients - in the form of DICOM files - will be imported into surgical&#xD;
      planning software (Mimics 19, Materialise, Leuven, Belgium). A segmentation process will be&#xD;
      accomplished by using the two dimensional CT cuts to define the image thresholds based on&#xD;
      Hounsfield's units, excluding soft tissue and only highlighting hard tissue (bone). The&#xD;
      maxilla/mandible region will be further isolated by cropping and/or region-growing functions&#xD;
      to remove artifacts and select only the area of interest, followed by the 3D calculation of&#xD;
      the selected regions. The 3D models will be exported in standard triangulation language (STL)&#xD;
      format.&#xD;
&#xD;
      The STL files will then be imported into computer-aided design (CAD) software (3-matic) in&#xD;
      order to create the design of the PSI. The subperiosteal part of the PSI will be drawn on the&#xD;
      surface of the region planned to receive the PSI and then extruded to a thickness of 2.5mm.&#xD;
      The PSIs will be meshed out with 2.5 mm holes to be compatible with 2.0 mm fixation screws.&#xD;
      For the single-piece PSI, the abutments will be placed, guided by the opposing teeth and the&#xD;
      radio-opaque dentures. As for the two-piece PSI, the same design will be repeated without the&#xD;
      addition of the abutment posts.&#xD;
&#xD;
      Fabrication of the patient-specific implant (PSI):&#xD;
&#xD;
      The STL file of the final design will be sent for 3D printing via additive manufacturing&#xD;
      using selective laser sintering (SLS) machine from medical titanium grade (Ti-6Al-4V) Extra&#xD;
      Low Interstitials (ELI).&#xD;
&#xD;
      PSI surface treatment:&#xD;
&#xD;
      The PSI will be subjected to acid etching following a protocol proposed by Juodzbalys et al&#xD;
      to attain micro roughness on the fitting surface of the implant. The PSIs will be etched with&#xD;
      sulfuric acid (H2SO4) for 72 hours followed by Hydrochloric acid (HCl) for 30 hours. After&#xD;
      removal from the acids PSIs will be washed in distilled water.&#xD;
&#xD;
      Cleaning and sterilization:&#xD;
&#xD;
      Implants will be cleaned in an ultrasonic bath of absolute ethyl alcohol solution at ambient&#xD;
      temperature for 30 minutes to ensure the removal of any residues on the fitting surface of&#xD;
      the implant. After being thoroughly cleaned, the PSIs will be wrapped and sterilized using a&#xD;
      class B autoclave.&#xD;
&#xD;
      Surgical phase:&#xD;
&#xD;
      For both groups, under general anesthesia; a mucosal incision 3-5 mm crestal to the vestibule&#xD;
      will be made in the anterior region similar to the genioplasty incision, followed by&#xD;
      dissection over the orbicularis oris and mentalis muscle and incising down to bone using a&#xD;
      scalpel blade #15c mounted on a Bard-Parker® surgical blade handle size 3, to expose the&#xD;
      proposed implant site. The incision will be completed posteriorly after localization of the&#xD;
      mental nerves. After bone exposure the implant will be installed in place and fixed with&#xD;
      2.0mm grade 5 titanium screws.&#xD;
&#xD;
      For two-piece PSIs, the framework will be designed with 3-4 mm endosseous projections at the&#xD;
      anticipated area where the final abutments will be fastened, guided by the position of the&#xD;
      teeth in the proposed prosthetic set-up. The endosseous projections will be designed in order&#xD;
      to accommodate the height of the internal connection that will receive the final abutment in&#xD;
      a second-stage surgery. Unlike single piece PSIs, bone-supported surgical guides will be&#xD;
      designed to aid in the placement and seating of the two-piece PSIs corresponding to the&#xD;
      preplanned osteotomy sites. The flap will be sutured in two layers; the muscle layer will be&#xD;
      closed with 3/0 poliglecaprone resorbable suture material and the mucosa with 4/0&#xD;
      Polypropylene non-resorbable suture material.&#xD;
&#xD;
      Postoperative care and instructions:&#xD;
&#xD;
      The intra oral wounds will be evaluated for any signs of bleeding, hematoma, infection, wound&#xD;
      dehiscence or PSI exposure after 48 hours, then weekly till the end of the first month. The&#xD;
      following medications will be administered:&#xD;
&#xD;
      Long acting corticosteroids: Methylprednisolone Acetate 40 mg/ml intramuscular injection&#xD;
      single dose immediate postoperative.&#xD;
&#xD;
      Anti-inflammatory analgesic: Ketorolac tromethamine 30 mg/amp/2mL intramuscular injection&#xD;
      every 12 hours for the first 24 hours followed by diclofenac potassium 50 mg tablets (every 8&#xD;
      hours for 4 days) Oral antibiotic: Ampicillin/sulbactam 375 mg tablets (every 8 hours for 10&#xD;
      days) Strict oral hygiene measures in the form of regular use of chlorohexidine Gluconate 125&#xD;
      mg/100 mL antiseptic mouth wash (every 8 hours for two weeks).&#xD;
&#xD;
      Prosthetic phase:&#xD;
&#xD;
      The steps of fabrication of the final prosthesis will be initiated 3 months after implant&#xD;
      placement for both groups. For the single-piece PSI group, a closed impression will be made.&#xD;
      For the two-piece PSI group, final abutments will be fastened to the corresponding connection&#xD;
      in the framework in a second stage surgery, followed by a final closed impression a week&#xD;
      later. The final restoration will be constructed from a high impact polymer composite (HIPC)&#xD;
      material via computer numerically controlled (CNC) milling. Occlusal adjustments will be&#xD;
      performed followed by temporary cementation for two weeks until a final approval is obtained&#xD;
      from the patient. Later, the prosthesis will be cemented using glass ionomer self-cured&#xD;
      luting cement.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Not yet recruiting</last_known_status>
  <start_date type="Anticipated">August 2017</start_date>
  <completion_date type="Anticipated">December 2020</completion_date>
  <primary_completion_date type="Anticipated">August 2020</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>None (Open Label)</masking>
    <masking_description>After assignment to interventions, blinding of trial participants, care providers and outcome assessors is not applicable. Data analysts will be blinded.</masking_description>
  </study_design_info>
  <primary_outcome>
    <measure>Implant survival</measure>
    <time_frame>12 months (post-surgery)</time_frame>
    <description>Implant survival will be assessed by evaluation of the following criteria:&#xD;
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.&#xD;
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Implant survival</measure>
    <time_frame>6 months (post-surgery)</time_frame>
    <description>Implant survival will be assessed by evaluation of the following criteria:&#xD;
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.&#xD;
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Implant survival</measure>
    <time_frame>3 months (post-surgery)</time_frame>
    <description>Implant survival will be assessed by evaluation of the following criteria:&#xD;
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.&#xD;
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Patient satisfaction</measure>
    <time_frame>At 1,3,6 and 12 months (after loading of final prosthesis)</time_frame>
    <description>Patient satisfaction is regarded an indicator of quality of healthcare. In this trial, the numerical rating scale (NRS) for patient satisfaction will be used, where patients will be asked to rate their satisfaction on the NRS (11-point ordinal scale) by selecting a whole number (0-10 integers), from 0 (completely dissatisfied) to 10 (completely satisfied). Higher scores portray higher satisfaction.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Soft tissue dehiscence</measure>
    <time_frame>At 1,3,6 and 12 months (post-surgery)</time_frame>
    <description>The investigators will subjectively assess this outcome through clinical examination of the oral tissues. It will be a binary outcome dichotomized to presence or absence of soft tissue breakdown based on the clinical examination.</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Anticipated">156</enrollment>
  <condition>Dental Implant</condition>
  <arm_group>
    <arm_group_label>Two-piece subperiosteal implant</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>The two-piece subperiosteal implant will be designed with an internal connection that will receive its prosthetic counterpart later in the second stage surgery, which will retain the final prosthesis in place. Two-piece constructions allow for undisturbed submerged healing, without being exposed to the oral environment, achieved by attaining primary closure over the inserted implant body.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Single-piece subperiosteal implant</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>The single-piece subperiosteal implant will be designed in the from of a framework with protruding posts that will appear penetrating through the mucosa, and will later carry the overlying superstructure (prosthesis). Single-piece subperiosteal implants do not require a second stage surgery.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Subperiosteal implant</intervention_name>
    <description>Subperiosteal implants are placed and fitted 'onto' the jaw bone just right below the mucoperiosteum; where the post of the metal frame is in a protruding position through the mucosa holding the prosthesis that will be later fitted.</description>
    <arm_group_label>Single-piece subperiosteal implant</arm_group_label>
    <arm_group_label>Two-piece subperiosteal implant</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Completely edentulous male or female patients with atrophied mandibles between the&#xD;
             ages of 50 to 75.&#xD;
&#xD;
          -  Atrophic mandibular ridges in terms of width and height, impeding the possibility of&#xD;
             placing a root form dental implant of at least 3mm in diameter and 8 mm in length.&#xD;
&#xD;
          -  Completely edentulous patients (with the above mentioned criteria) who can't stand a&#xD;
             soft-tissue supported mandibular denture.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Patients having a medical condition that absolutely contraindicates implant placement.&#xD;
&#xD;
          -  Patients with uncontrolled diabetes, assessed by measuring glycosylated haemoglobin&#xD;
             (HbA1c). Patients with an HbA1c level greater than 8 will be excluded.&#xD;
&#xD;
          -  Potentially uncooperative patients who are not willing to go through the proposed&#xD;
             interventions.&#xD;
&#xD;
          -  Moderate-to-heavy daily smokers* (who report consuming at least 11 cigarettes/day).&#xD;
&#xD;
          -  Patients who are satisfied with their soft-tissue supported mandibular denture.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>50 Years</minimum_age>
    <maximum_age>75 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Mariam A. Roshdy</last_name>
    <role>Principal Investigator</role>
    <affiliation>Assistant lecturer, Department of Prosthodontics, Cairo University</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Cairo University</name>
      <address>
        <city>Giza</city>
        <country>Egypt</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Egypt</country>
  </location_countries>
  <reference>
    <citation>Sconzo J. The complete mandibular subperiosteal implant: an overview of its evolution. J Oral Implantol. 1998;24(1):14-5. doi: 10.1563/1548-1336(1998)242.0.CO;2. No abstract available.</citation>
    <PMID>9759036</PMID>
  </reference>
  <reference>
    <citation>Burns DR, Unger JW, Elswick RK Jr, Beck DA. Prospective clinical evaluation of mandibular implant overdentures: Part I--Retention, stability, and tissue response. J Prosthet Dent. 1995 Apr;73(4):354-63. doi: 10.1016/s0022-3913(05)80331-2.</citation>
    <PMID>7783014</PMID>
  </reference>
  <reference>
    <citation>Aras E, Sonmez M, Zora M, Basarir M, Kurtulmus H. The use of prefabricated titanium tissue abutments for the construction of a maxillary subperiosteal implant. J Oral Implantol. 2005;31(5):255-8. doi: 10.1563/1548-1336(2005)31[255:TUOPTT]2.0.CO;2.</citation>
    <PMID>16265856</PMID>
  </reference>
  <reference>
    <citation>OBWEGESER HL. Experiences with subperiosteal implants. Oral Surg Oral Med Oral Pathol. 1959 Jul;12(7):777-86. doi: 10.1016/0030-4220(59)90027-1. No abstract available.</citation>
    <PMID>13674677</PMID>
  </reference>
  <reference>
    <citation>The glossary of prosthodontic terms. J Prosthet Dent. 2005 Jul;94(1):10-92. doi: 10.1016/j.prosdent.2005.03.013. No abstract available.</citation>
    <PMID>16080238</PMID>
  </reference>
  <reference>
    <citation>Weiss CM, Reynolds T. A collective conference on the utilization of subperiosteal implants in implant dentistry. J Oral Implantol. 2000;26(2):127-8. doi: 10.1563/1548-1336(2000)262.0.CO;2. No abstract available.</citation>
    <PMID>11831330</PMID>
  </reference>
  <reference>
    <citation>Falomo OO, Hobkirk JA. A retrospective survey of patients treated with subperiosteal and endosseous implants. J Prosthet Dent. 1988 Nov;60(5):587-90. doi: 10.1016/0022-3913(88)90219-3. No abstract available.</citation>
    <PMID>3058941</PMID>
  </reference>
  <reference>
    <citation>Williamson A, Hoggart B. Pain: a review of three commonly used pain rating scales. J Clin Nurs. 2005 Aug;14(7):798-804. doi: 10.1111/j.1365-2702.2005.01121.x.</citation>
    <PMID>16000093</PMID>
  </reference>
  <reference>
    <citation>Juodzbalys, G., M. Sapragoniene, and A. Wennerberg, New acid etched titanium dental implant surface. Stomatologija-Baltic Dental and Maxillofacial Journal, 2003. 5: p. 101-105.</citation>
  </reference>
  <verification_date>August 2017</verification_date>
  <study_first_submitted>July 31, 2017</study_first_submitted>
  <study_first_submitted_qc>August 3, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">August 8, 2017</study_first_posted>
  <last_update_submitted>August 3, 2017</last_update_submitted>
  <last_update_submitted_qc>August 3, 2017</last_update_submitted_qc>
  <last_update_posted type="Actual">August 8, 2017</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Cairo University</investigator_affiliation>
    <investigator_full_name>Mariam Ahmed Roshdy</investigator_full_name>
    <investigator_title>Assistant lecturer, Department of Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University</investigator_title>
  </responsible_party>
  <keyword>Implant survival</keyword>
  <keyword>Patient satisfaction</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/NCT03242330
org study id: Cairo Uni
nct id: NCT03242330
lead sponsor: 
has dmc: Yes
is fda regulated drug: No
is fda regulated device: No
The objective of this trial is to find out if there is a difference between single-piece and
      two-piece titanium patient-specific mandibular subperiosteal implants in terms of implant
      survival, patient satisfaction, and soft tissue dehiscence. This is to enhance both surgical
      and prosthetic outcomes for the sake of improved implant longevity, soft tissue health and
      patient well-being.
After obtaining a thorough medical and dental history and performing necessary laboratory
      investigations, the following steps will be undertaken:

      Preoperative prosthetic preparation:

        -  For eligible patients who are already wearing upper and lower complete dentures: The
           dentures will be checked for adaptation, fit, stability and occlusion.

        -  For eligible patients who are not wearing upper and lower complete dentures:

      Preliminary alginate impressions will be made using a perforated stock tray for both the
      maxillary and mandibular arches. Impressions are then poured into dental stone to obtain the
      diagnostic models. Occlusion blocks will be constructed over the diagnostic models, followed
      by bite registration, try-in and delivery of upper and lower complete dentures.

      Afterwards, approved complete dentures will be duplicated using laboratory condensation
      silicone to construct a radiographic stent. The radiographic stent is prepared by using a
      ratio of 3:1 acrylic resin to barium sulphate mixture, and then the patient is sent for a
      Cone Beam Computed Tomography (CBCT) scan.

      CBCT scanning and virtual design of the patient-specific implant (PSI):

      The CBCT scan of the patients - in the form of DICOM files - will be imported into surgical
      planning software (Mimics 19, Materialise, Leuven, Belgium). A segmentation process will be
      accomplished by using the two dimensional CT cuts to define the image thresholds based on
      Hounsfield's units, excluding soft tissue and only highlighting hard tissue (bone). The
      maxilla/mandible region will be further isolated by cropping and/or region-growing functions
      to remove artifacts and select only the area of interest, followed by the 3D calculation of
      the selected regions. The 3D models will be exported in standard triangulation language (STL)
      format.

      The STL files will then be imported into computer-aided design (CAD) software (3-matic) in
      order to create the design of the PSI. The subperiosteal part of the PSI will be drawn on the
      surface of the region planned to receive the PSI and then extruded to a thickness of 2.5mm.
      The PSIs will be meshed out with 2.5 mm holes to be compatible with 2.0 mm fixation screws.
      For the single-piece PSI, the abutments will be placed, guided by the opposing teeth and the
      radio-opaque dentures. As for the two-piece PSI, the same design will be repeated without the
      addition of the abutment posts.

      Fabrication of the patient-specific implant (PSI):

      The STL file of the final design will be sent for 3D printing via additive manufacturing
      using selective laser sintering (SLS) machine from medical titanium grade (Ti-6Al-4V) Extra
      Low Interstitials (ELI).

      PSI surface treatment:

      The PSI will be subjected to acid etching following a protocol proposed by Juodzbalys et al
      to attain micro roughness on the fitting surface of the implant. The PSIs will be etched with
      sulfuric acid (H2SO4) for 72 hours followed by Hydrochloric acid (HCl) for 30 hours. After
      removal from the acids PSIs will be washed in distilled water.

      Cleaning and sterilization:

      Implants will be cleaned in an ultrasonic bath of absolute ethyl alcohol solution at ambient
      temperature for 30 minutes to ensure the removal of any residues on the fitting surface of
      the implant. After being thoroughly cleaned, the PSIs will be wrapped and sterilized using a
      class B autoclave.

      Surgical phase:

      For both groups, under general anesthesia; a mucosal incision 3-5 mm crestal to the vestibule
      will be made in the anterior region similar to the genioplasty incision, followed by
      dissection over the orbicularis oris and mentalis muscle and incising down to bone using a
      scalpel blade #15c mounted on a Bard-Parker® surgical blade handle size 3, to expose the
      proposed implant site. The incision will be completed posteriorly after localization of the
      mental nerves. After bone exposure the implant will be installed in place and fixed with
      2.0mm grade 5 titanium screws.

      For two-piece PSIs, the framework will be designed with 3-4 mm endosseous projections at the
      anticipated area where the final abutments will be fastened, guided by the position of the
      teeth in the proposed prosthetic set-up. The endosseous projections will be designed in order
      to accommodate the height of the internal connection that will receive the final abutment in
      a second-stage surgery. Unlike single piece PSIs, bone-supported surgical guides will be
      designed to aid in the placement and seating of the two-piece PSIs corresponding to the
      preplanned osteotomy sites. The flap will be sutured in two layers; the muscle layer will be
      closed with 3/0 poliglecaprone resorbable suture material and the mucosa with 4/0
      Polypropylene non-resorbable suture material.

      Postoperative care and instructions:

      The intra oral wounds will be evaluated for any signs of bleeding, hematoma, infection, wound
      dehiscence or PSI exposure after 48 hours, then weekly till the end of the first month. The
      following medications will be administered:

      Long acting corticosteroids: Methylprednisolone Acetate 40 mg/ml intramuscular injection
      single dose immediate postoperative.

      Anti-inflammatory analgesic: Ketorolac tromethamine 30 mg/amp/2mL intramuscular injection
      every 12 hours for the first 24 hours followed by diclofenac potassium 50 mg tablets (every 8
      hours for 4 days) Oral antibiotic: Ampicillin/sulbactam 375 mg tablets (every 8 hours for 10
      days) Strict oral hygiene measures in the form of regular use of chlorohexidine Gluconate 125
      mg/100 mL antiseptic mouth wash (every 8 hours for two weeks).

      Prosthetic phase:

      The steps of fabrication of the final prosthesis will be initiated 3 months after implant
      placement for both groups. For the single-piece PSI group, a closed impression will be made.
      For the two-piece PSI group, final abutments will be fastened to the corresponding connection
      in the framework in a second stage surgery, followed by a final closed impression a week
      later. The final restoration will be constructed from a high impact polymer composite (HIPC)
      material via computer numerically controlled (CNC) milling. Occlusal adjustments will be
      performed followed by temporary cementation for two weeks until a final approval is obtained
      from the patient. Later, the prosthesis will be cemented using glass ionomer self-cured
      luting cement.
allocation: Randomized
intervention model: Parallel Assignment
primary purpose: Treatment
masking: None (Open Label)
masking description: After assignment to interventions, blinding of trial participants, care providers and outcome assessors is not applicable. Data analysts will be blinded.
measure: Implant survival
time frame: 12 months (post-surgery)
description: Implant survival will be assessed by evaluation of the following criteria:
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate
measure: Implant survival
time frame: 6 months (post-surgery)
description: Implant survival will be assessed by evaluation of the following criteria:
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate
measure: Implant survival
time frame: 3 months (post-surgery)
description: Implant survival will be assessed by evaluation of the following criteria:
a) Persistent pain, and/or b) mobility and/or c) persistent exudate In case of presence of one or more of the previously mentioned criteria, implants will be regarded non-survived.
Presence of persistent pain either spontaneous or during function Presence of clinically detected mobility Evidence of infection in the form of pus formation or persistent inflammatory fluid exudate
measure: Patient satisfaction
time frame: At 1,3,6 and 12 months (after loading of final prosthesis)
description: Patient satisfaction is regarded an indicator of quality of healthcare. In this trial, the numerical rating scale (NRS) for patient satisfaction will be used, where patients will be asked to rate their satisfaction on the NRS (11-point ordinal scale) by selecting a whole number (0-10 integers), from 0 (completely dissatisfied) to 10 (completely satisfied). Higher scores portray higher satisfaction.
measure: Soft tissue dehiscence
time frame: At 1,3,6 and 12 months (post-surgery)
description: The investigators will subjectively assess this outcome through clinical examination of the oral tissues. It will be a binary outcome dichotomized to presence or absence of soft tissue breakdown based on the clinical examination.
arm group label: Two-piece subperiosteal implant
arm group type: Experimental
description: The two-piece subperiosteal implant will be designed with an internal connection that will receive its prosthetic counterpart later in the second stage surgery, which will retain the final prosthesis in place. Two-piece constructions allow for undisturbed submerged healing, without being exposed to the oral environment, achieved by attaining primary closure over the inserted implant body.
arm group label: Single-piece subperiosteal implant
arm group type: Active Comparator
description: The single-piece subperiosteal implant will be designed in the from of a framework with protruding posts that will appear penetrating through the mucosa, and will later carry the overlying superstructure (prosthesis). Single-piece subperiosteal implants do not require a second stage surgery.
intervention type: Device
intervention name: Subperiosteal implant
description: Subperiosteal implants are placed and fitted 'onto' the jaw bone just right below the mucoperiosteum; where the post of the metal frame is in a protruding position through the mucosa holding the prosthesis that will be later fitted.
arm group label: Single-piece subperiosteal implant
arm group label: Two-piece subperiosteal implant
criteria: 
gender: All
minimum age: 50 Years
maximum age: 75 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Mariam A. Roshdy
role: Principal Investigator
affiliation: Assistant lecturer, Department of Prosthodontics, Cairo University
facility: 
country: Egypt
citation: Sconzo J. The complete mandibular subperiosteal implant: an overview of its evolution. J Oral Implantol. 1998;24(1):14-5. doi: 10.1563/1548-1336(1998)242.0.CO;2. No abstract available.
PMID: 9759036
citation: Burns DR, Unger JW, Elswick RK Jr, Beck DA. Prospective clinical evaluation of mandibular implant overdentures: Part I--Retention, stability, and tissue response. J Prosthet Dent. 1995 Apr;73(4):354-63. doi: 10.1016/s0022-3913(05)80331-2.
PMID: 7783014
citation: Aras E, Sonmez M, Zora M, Basarir M, Kurtulmus H. The use of prefabricated titanium tissue abutments for the construction of a maxillary subperiosteal implant. J Oral Implantol. 2005;31(5):255-8. doi: 10.1563/1548-1336(2005)31[255:TUOPTT]2.0.CO;2.
PMID: 16265856
citation: OBWEGESER HL. Experiences with subperiosteal implants. Oral Surg Oral Med Oral Pathol. 1959 Jul;12(7):777-86. doi: 10.1016/0030-4220(59)90027-1. No abstract available.
PMID: 13674677
citation: The glossary of prosthodontic terms. J Prosthet Dent. 2005 Jul;94(1):10-92. doi: 10.1016/j.prosdent.2005.03.013. No abstract available.
PMID: 16080238
citation: Weiss CM, Reynolds T. A collective conference on the utilization of subperiosteal implants in implant dentistry. J Oral Implantol. 2000;26(2):127-8. doi: 10.1563/1548-1336(2000)262.0.CO;2. No abstract available.
PMID: 11831330
citation: Falomo OO, Hobkirk JA. A retrospective survey of patients treated with subperiosteal and endosseous implants. J Prosthet Dent. 1988 Nov;60(5):587-90. doi: 10.1016/0022-3913(88)90219-3. No abstract available.
PMID: 3058941
citation: Williamson A, Hoggart B. Pain: a review of three commonly used pain rating scales. J Clin Nurs. 2005 Aug;14(7):798-804. doi: 10.1111/j.1365-2702.2005.01121.x.
PMID: 16000093
citation: Juodzbalys, G., M. Sapragoniene, and A. Wennerberg, New acid etched titanium dental implant surface. Stomatologija-Baltic Dental and Maxillofacial Journal, 2003. 5: p. 101-105.
responsible party type: Principal Investigator
investigator affiliation: Cairo University
investigator full name: Mariam Ahmed Roshdy
investigator title: Assistant lecturer, Department of Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University
sharing ipd: No