Histological and Histomorphometric Assessment With Inflammatory Profile Analysis of Bone Tissue After Horizontal Ridge Augmentation Using Customized Porous Zirconia Shell

September 26, 2026 updated by: Mohammed Mahmoud Abed

Histological and Histomorphometric Assessment With Inflammatory Profile Analysis of Bone Tissue After Horizontal Ridge Augmentation of the Lower Posterior Mandible Using a Novel Customized Porous Zirconia Shell Technique: Clinical Case Study

The goal of this clinical study is to learn whether a custom-made porous zirconia shell can support good-quality new bone when widening the lower back jaw before dental implant placement. The study includes adults whose jawbone in this area is too narrow for implants (Seibert Class I defects).

The main question it aims to answer is: What is the quality of the new bone formed under a porous zirconia shell, and how much inflammation does the tissue show?

Participants will:

  • Receive gum treatment and a CBCT scan before surgery
  • Have bone augmentation surgery, in which a digitally designed porous zirconia shell is fixed over a mixture of their own bone and xenograft
  • Return after 2 weeks for suture removal and a check of the wound
  • Return after 6 months for a CBCT scan, removal of the shell, collection of a small bone sample (biopsy), and dental implant placement

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Horizontal bone loss in the posterior mandible often prevents dental implant placement. The Khoury technique uses thin autogenous cortical bone plates to rebuild the ridge, but harvesting these plates causes donor-site morbidity, is technically demanding, and is limited by available bone. Zirconia is biocompatible, mechanically strong and osteoconductive, and has shown low inflammatory response. However, it has not been studied as a shell replacing autogenous bone plates.

In this single-arm study, 10 adults with Seibert Class I defects in the posterior mandible will first receive non-surgical periodontal therapy. Compliance will be checked after 1 month. A zirconia shell with 1.5 mm pores will be digitally designed from each patient's CBCT scan, milled on a 5-axis machine, then cleaned and sterilized.

Under local anesthesia, buccal and lingual full-thickness flaps will be raised and the recipient bone decorticated. Autogenous bone chips will be harvested from the mandibular body with a bone chip maker and mixed 1:1 with xenograft. The shell will be fixed over the graft with 3-4 buccal screws. The flaps will be advanced and closed with a double-layer suture.

After 6 months, the shell will be removed, a core biopsy will be taken, and an implant will be placed. The biopsies will be fixed in 10% formalin and analyzed histologically, histomorphometrically and for tissue inflammatory response.

Study Type

Interventional

Enrollment (Estimated)

10

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Egypt
    • Giza Governorate
      • Giza, Giza Governorate, Egypt
        • Recruiting
        • October University for Modern Sciences and Arts (MSA), Faculty of Dentistry
        • Contact:
        • Contact:
        • Sub-Investigator:
          • Ahmed Reda Abd Elrahman, PhD
        • Principal Investigator:
          • Mohammed Mahmoud Abed, BDS
        • Sub-Investigator:
          • Nada Abdelmonem Zazou, PhD
        • Sub-Investigator:
          • Mahmoud Ibrahim Nassar, PhD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Age more than 21 years old
  • Horizontal bone loss in the lower posterior area (Seibert Class I)
  • Enough inter-arch space for placement of implant-supported prosthesis
  • Motivated patient to have the treatment
  • Good oral hygiene

Exclusion Criteria:

  • Patients with systemic conditions that could interfere with the healing process
  • Pregnant females
  • Smokers
  • Poor oral hygiene

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Customized Porous Zirconia Shell

Participants with horizontal bone defects in the posterior mandible receive ridge augmentation using a patient-specific porous zirconia shell fixed over a 1:1 mixture of autogenous bone and xenograft. After 6 months, the shell is removed, a bone biopsy is taken, and a dental implant is placed.
Device: Customized porous zirconia shell

A CAD/CAM-milled zirconia shell with 1.5 mm pores, designed from each patient's CBCT scan and fixed with 3-4 buccal screws over a 1:1 mix of autogenous bone chips and xenograft. It replaces the autogenous cortical plates used in the Khoury technique and is removed after 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Quality of Newly Formed Bone Assessed by Descriptive Histological Analysis of the Core Biopsy
Time Frame: 6 months after ridge augmentation (at shell removal and implant placement)

Histological analysis of the core bone biopsy harvested from the augmented site. Specimens will be fixed in a 10% formalin solution. Descriptive analysis of the cells and tissue structure of the augmented site within the biopsy (Dellavia et al., 2021).
6 months after ridge augmentation (at shell removal and implant placement)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of Newly Formed Bone (% of Total Biopsy Area)
Time Frame: 6 months after augmentation

Histomorphometric measurement of the new bone area as a percentage of the total biopsy area.
6 months after augmentation
Percentage of Residual Graft Material (% of Total Biopsy Area)
Time Frame: 6 months after augmentation

Histomorphometric measurement of the remaining graft particle area as a percentage of the total biopsy area.
6 months after augmentation
Percentage of Soft Tissue (% of Total Biopsy Area)
Time Frame: 6 months after augmentation

Histomorphometric measurement of the non-mineralized connective tissue area as a percentage of the total biopsy area.
6 months after augmentation
Inflammatory Cell Infiltration Score
Time Frame: 6 months after augmentation

Semi-quantitative tissue response score from 0 (no inflammatory cells) to 4 (severe cellular infiltrate or tissue necrosis), based on the presence of lymphocytes, macrophages, foreign body giant cells, eosinophils and neutrophils.
6 months after augmentation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Mohammed Mahmoud Abed

Investigators

  • Study Director: Nada Abdelmonem Zazou, PhD, October University for Modern Sciences and Arts (MSA)
  • Study Chair: Ahmed Reda Abd Elrahman, PhD, October University for Modern Sciences and Arts (MSA)
  • Study Director: Mahmoud Ibrahim Nassar, PhD, October University for Modern Sciences and Arts (MSA)

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 15, 2025

Primary Completion (Estimated)

May 1, 2027

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

September 16, 2026

First Submitted That Met QC Criteria

September 24, 2026

First Posted (Actual)

September 25, 2026

Study Record Updates

Last Update Posted (Actual)

September 30, 2026

Last Update Submitted That Met QC Criteria

September 26, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • REC-D 6206-5

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared to protect patient confidentiality, as stated in the approved protocol. Study results will be published in a peer-reviewed dental journal.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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