Effect of Healing Time on New Bone Formation Following Tooth Extraction and Ridge Preservation With Demineralized Freeze-Dried Bone Allograft
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 46
- Locations
- 2
- Primary Endpoint
- Percent New Vital Bone Formation
Study Overview
Brief Summary
Bone grafting following tooth extraction is commonly performed to preserve bony ridge dimensions adequate to support subsequent implant placement. Alveolar ridge resorption commonly occurs following tooth extraction, and the decrease in bone volume has the potential to make dental implant therapy impossible without surgery to reconstruct the ridge. The aim of ridge preservation grafting is to prevent or minimize this resorptive process, thereby preserving an adequate volume of bone for implant placement. Ridge preservation generally involves placement of a particulate bone graft material in the tooth socket, followed by use of a membrane or similar substance over the socket entrance to contain the bone graft. Various grafting materials have been recommended for these ridge preservation procedures, including demineralized freeze-dried bone allograft (DFDBA). The timing of dental implant placement following ridge preservation procedures is controversial, and few studies have examined the effects of different healing time intervals between ridge preservation and implant placement. The purpose of this project is to evaluate the formation of new bone at a site where tooth extraction has been performed followed by grafting using DFDBA. Two different study groups are included, one having the dental implant placed 8-10 weeks after tooth extraction and ridge grafting, the other having the dental implant placed 18-20 weeks after extraction and grafting.
Detailed Description
The purpose of this study is to compare healing following tooth extraction and ridge preservation with DFDBA at a healing time point 8-10 weeks after treatment compared to a healing time point 18-20 weeks after treatment. There have been no studies to determine differences in new bone formation using DFDBA for this purpose at various healing time points post-grafting. The primary objective is to histologically determine the amount of new bone formation and residual graft material present at the two healing time points after grafting with DFDBA. Histologic healing will be compared based on three criteria: % of new vital bone formation, % of residual graft material, and % of nonmineralized connective tissue/bone marrow. The null hypothesis is that there will be no difference between the % new bone formation at 8-10 weeks after grafting compared to 18-20 weeks after grafting.
This entire protocol involves procedures that are standard care. There will be two subject groups in this study. All subjects will require extraction of a non-molar tooth, followed by replacement of the missing tooth with a dental implant. In order to ensure that the bone core removed during implant osteotomy preparation is taken totally within the confines of the former tooth socket, the tooth to be extracted will have a position and angulation that is the same as the implant that will replace the tooth. Each group will have 22 subjects. Only one tooth will be evaluated in any given subject.
Both groups will consist of subjects who will have cortical DFDBA grafted into the extraction socket for ridge preservation following tooth extraction. Group 1 will have a biopsy core taken at the time of implant placement 8-10 weeks after socket grafting. Group 2 will have a biopsy core taken at the time of implant placement 18-20 weeks after socket grafting. Allocation of subjects into group 1 or 2 will based on randomization once enrolled into the study. Subjects will be asked to draw a sealed envelope out of a stack of envelopes, each containing a single slip of paper coded with #1 or a #2. This will determine the treatment group.
All of the bone graft materials used in this study will come from the same donor (LifeNet Health). The materials will be procured and processed in the same manner and will have the same particle size and percent residual calcium. This greatly decreases potential variability inherent in bone taken from different donors or processed in different manners.
At the time of subject enrollment, the following standard care procedures will be performed: Impressions will be made for fabrication of diagnostic casts and radiographs will be taken of the tooth to be extracted. A clear measurement stent will be made on the cast for vertical and horizontal ridge dimensions.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 89 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Patient currently a patient at dental school or eligible for treatment at dental school
- •Patient resides within 50 mile radius of dental school
- •A single rooted tooth that has been identified by dental faculty as requiring extraction
- •Have adequate restorative space for a dental implant-retained restoration
- •Have at least 10mm of alveolar bone height, without impinging on the maxillary sinus or inferior alveolar canal.
- •Have a dehiscence of the buccal or lingual bony plate of the tooth socket extending no more than 50% of the total depth of the socket.
- •Female patients who have undergone a hysterectomy, tubal ligation, or menopause, and non-pregnant women of child-bearing potential.
Exclusion Criteria
- •not meeting inclusion criteria above
- •Active localized or systemic infection other than periodontitis.
- •Inadequate bone dimensions or restorative space dimensions to place a dental implant
- •Presence of a disease entity, medical condition or therapeutic regimen which decreases probability of soft tissue and bony healing, e.g., poorly controlled diabetes, chemotherapeutic and immunosuppressive agents, autoimmune diseases, history of bisphosphonate use or long-term steroid therapy.
- •Positive medical history of endocarditis following oral or dental surgery.
- •Sensitivity or allergy to Bacitracin, Gentamicin, Polymyxin B Sulfate, alcohol and/or surfactants (per package insert)
Outcomes
Primary Outcomes
Percent New Vital Bone Formation
Time Frame: after removal of bone core from site of dental implant placement at 18-20 weeks following tooth extraction and grafting
Bone core biopsy will be evaluated histologically for percent new vital bone formation
Secondary Outcomes
- Change in Buccal Ridge Height(at time of implant placement at 8-10 or 18-20 weeks following tooth extraction and grafting)
- Change in Ridge Width(at time of implant placement at 8-10 or 18-20 weeks following tooth extraction and grafting)
Investigators
Brian L Mealey
Graduate Program Director, Periodontics
The University of Texas Health Science Center at San Antonio