An RCT Comparing Xenograft and Allograft for Ridge Preservation

Not Applicable

Completed

Interventions: Device: allograft + x-link collagen membrane
Device: xenograft + non-x-link collagen

Brief Summary: To compare the effectiveness of demineralized freeze-dried bone allograft + cross-linked collagen membrane with xenograft + non-cross-linked collagen membrane for posterior extraction socket ridge preservation.

Detailed Description: Buccal bony wall loss is a common sequela following tooth extraction, and guided bone regeneration (GBR) is a common treatment for the regeneration of ridge form and volume preservation allowing dental implant placement. Many bone augmentation biomaterials are employed to accomplish GBR, and both the medical/ dental community and, subsequently, patients benefit from understanding whether a given GBR biomaterial might be more efficacious. To this end, a randomized, case series comparison of allograft + x-linked collagen membrane versus xenograft + non-x-linked collagen membrane would be beneficial to both the dental community and patients.

The study compares the effectiveness of demineralized freeze-dried bone allograft + x-linked collagen membrane with xenograft + non-x-linked collagen membrane for posterior region extraction socket ridge preservation.

Recruitment & Eligibility

Inclusion Criteria

Subjects 18 to 70-yrs of age
Subject indicated for posterior tooth extraction (from 1st premolar to 1st molar) intended for implant placement, with adjacent teeth intact (for stent indexing)
Subjects with extraction site bony buccal dehiscences at least 1/3 the depth of socket and 1/3 the mesial-distal width of tooth socket
Subjects will have read, understood and signed an institutional review board (IRB) approved Informed Consent Form (ICF).
Subjects must be able and willing to follow study procedures and instructions.

Exclusion Criteria

Subjects with a history of any tobacco use within the last six months.
Subjects with healing disorders (i.e., diabetes mellitus, cancer, HIV, bone metabolic diseases) that could compromise wound healing and/ or preclude implant surgery; or who are currently receiving or have received within two months prior to study entry, systemic corticosteroids, immunosuppressive agents, radiation therapy, and/or chemotherapy which could compromise wound healing and preclude periodontal surgery.
Subjects taking intramuscular or intravenous bisphosphonates.
Subjects who have a known allergy or sensitivity to alginate, latex, collagen or acrylic.
Female subjects who are pregnant or lactating, or who intend to become pregnant during the study duration
Subjects participating in other clinical studies involving therapeutic intervention (either medical or dental).
Subjects, who in the opinion of the investigator, for any reason other than those listed above, will not be able to complete the study per protocol.

Arm && Interventions

Group	Intervention	Description
allograft + x-link collagen membrane	allograft + x-link collagen membrane	Demineralized freeze-dried allograft + x-linked collagen membrane will be used for guided bone regeneration of dehiscence buccal defects post extraction.
xenograft + non-x-link collagen	xenograft + non-x-link collagen	Xenograft + non-x-linked collagen membrane will be used for guided bone regeneration of dehiscence buccal defects post extraction.

Primary Outcome Measures

Name	Time	Method
Bone Ridge Buccal-Lingual and Apico-Coronal Measures at 6 Months	Six Months	The primary efficacy parameter will be ridge volume preservation as measured apico-coronal and buccal-lingual using a preformed and marked stent.

Secondary Outcome Measures

Name	Time	Method
Wound Closure at 4-weeks	4-weeks	Suture line gap will be measured (buccal-lingual) with a UNC-15 Probe, rounding down to the nearest 0.5 mm.
New Bone Plus Graft Content at 6-months	Six Months	New bone and graft content are measured as histomorphometric % vital bone and % mineral (graft remnants) from mid-section bone core biopsies. Histomorphometric analyses are performed with imaging software on composite overview scans. The area of new healing (versus old/ original bony tissues) is demarcated in each section. Within this area, the percentage contributions of each tissue type within the overall area of newly healed tissue is computed, i.e., new bone plus graft content added with connective tissue/ marrow elements totals 100% of the "new healing" area.