long-term safety and performance of Ivory Dentin Graft. Ivory Dentin Graft is at least as good as the competitor treatment group (OsteoBiol Gen-Os) for alveolar ridge preservation following tooth extraction.

This clinical investigation is part of the post-market development process of the investigational device of Ivory Graft Ltd. in order to satisfactory validate the safety, tolerability and effectiveness of Ivory Dentin Graft as required by the sponsor's European Union (EU) notified body.

The clinical Investigation was conducted with the stated confirmation applying European regulations; International Conference of Harmonization - Good Clinical Practice (ICH-GCP) guidelines, ISO 14155:2011, and with a relevant subject population for the study objectives. Israeli Ministry of Health registration Number: 20173907.

The purpose of this investigation is to evaluate the safety, tolerability and effectiveness of Ivory Dentin Graft for long-term evaluations, compared to the active comparator, OsteoBiol-Gen-Os® graft, as a treatment for alveolar ridge preservation following tooth extraction.

Long term follow-up: from completion of visit 5 (implant placement) up to 5 years from bone grafting per subject (visits 6-9).

Study design: A prospective, randomized, semi double-blinded with blinded assessments clinical investigation, comparing between subjects grafted with Ivory Dentin Graft (Investigational group) and subjects grafted with OsteoBiol-Gen-Os® (comparator group)

Study population: A total of 41 male and female adult subjects between the ages of 18 to 80 years old requiring alveolar ridge preservation that already had mandibular premolar or molar tooth extraction were included to this ongoing study (NCT03150472; short-term follow-up of 4 months following grafting was completed on September 9, 2020). Twenty-three (23) were previously randomized and grafted with Ivory Dentin Graft (Investigational group) and 18 with the active comparator, OsteoBiol Gen-Os (Comparator group). Five (5) subjects early withdrawn the short-term study resulting in 36 subjects included for this long-term study.

Sample size Justification and Statistical Analysis Plan: The rationale for sample size calculation is based on demonstrating non-inferiority in the study primary endpoint between the investigational and the reference comparator groups. The calculations assume a difference of up to 30% (percent as in unit of measure and not of relative difference) woven bone between the treatments, which will be considered equivalent (non-inferiority) and standard deviation of 32%.

Intended Use: bone graft material for the repair or augmentation of bone defects in dental procedures.

Clinical Follow-up: subjects are medically monitored for any long-term side effects (6 and 10 months, 2.5 and 5 years following their grafting procedure) and their dental condition is also followed by dental hygienist.

Inclusion Criteria:

1. Male or female patient 18 up to 80 years.

2. Patient requiring at least one implant placement following mandibular pre-molar or molar tooth extraction.

3. Alveolar mandibular ridge (empty socket):

   • Height: not less than 10 mm, from the gingival margin to the mandibular nerve canal - as seen in the screening CT scan.
   • Width: not less than 5 mm, from buccal to lingual cortical plates - as seen in the screening CT scan.

4. Ability to give informed consent for the study by patient or legal guardian.

5. Willingness to undergo 7 follow up visits: 1 week, 1, 4, 6 and 10 months, 2.5 years and 5 years following dental graft implantation, as well as unscheduled sick visits.

   Exclusion Criteria:

6. Pregnancy (all women of childbearing age would be questioned and told by the consenting physician regarding that criteria).

7. Known or suspected hypersensitivity to the constituents of the bone graft material (for example porcine collagen)

8. Pathologies or conditions contraindicating surgery or presenting with active acute or chronic infections excluding periapical granuloma (for example osteomyelitis, sinusitis), uncontrolled diabetes

9. Immunologic disorders or autoimmune pathologies, in particular elderly

10. Serious bone diseases of endocrine aetiology

11. Serious disturbances of bone metabolism

12. Ongoing treatment with gluco- or mineralocorticoids, or with agents affecting calcium metabolism (e.g. calcitonin, bisphosphonates)

13. Irradiation therapy, chemotherapy or immunosuppressive therapy in the last 5 years

14. Malignancies

15. Severe Parafunction (bruxism and clenching)

16. Poor oral hygiene or active periodontitis

17. Heavy tobacco smoking habit (> 10 cigarettes per day)

IPD is not intended to be shared as this will be a single site study. The study will be public at ClinicalTrial.gov

Only the graft performing sub-investigator and the study coordinator are un-blinded to subjects allocation - semi double blinded study.