Amnion-Chorion Allograft Barrier Used for Root Surface and Guided Tissue Regeneration

Patients who are referred to the Graduate Periodontics Clinic at Indiana University School of Dentistry for the treatment of severe chronic/aggressive periodontitis will be screened for possible participation in this study. Up to 20 subjects will be accepted into this study.

Written informed consent and authorization will be obtained from all participants and they will be given a copy of the signed informed consent documents.

The procedures listed below are all within standard care for a regenerative therapy around the teeth except the application of the membrane on the root surface prior to the bone grafting. No data collected for this study will be taken from sources outside of that already recorded for standard of care procedures.

Clinical Measurements A single calibrated examiner will perform clinical baseline and 6-month follow up measurements. O'Leary plaque score will be assessed. Six sites of each tooth of probing depth (PD), recession (REC) and clinical attachment level (CAL) will be recorded to the nearest millimeter with a University of North Carolina Probe (UNC Probe). For Glickman grade II furcation defects, in addition to the previous measurements, vertical probing pocket depth (VPD) and horizontal probing depth (HPD) will be measured.

Radiographic assessment will be performed with vertical bite-wing radiographs at baseline and 6-month post-surgical treatment. In order to maximize the standardization of the angulation of radiographs, bite registration will be taken prior to the first radiograph and utilized with beam-guiding device. It will be stored to be used post operatively. Sirona Dental Systems© with 7mA 60kV with 0.16s exposure time will be utilized for all radiographs. Digital #2 films manufactured by Air Techniques Inc. will be used for radiographic assessment. Bony defect (BD) will be defined as the most coronal point where the periodontal ligament space showed a continuous width. If several bony contours could be identified, the most apical one that crossed the root will be defined as the boney defect and the most coronal one as alveolar crest. If the cemento-enamel junction (CEJ) was destroyed by the restorative treatment, the margin of the restoration will be taken as a landmark. Beam guided device will be used as a calibration of measurements. The change of bone fill and angulation will be recorded.

All surgery will be rendered at the Graduate Periodontics Clinic at Indiana University School of Dentistry. All the patients will be treated under local anesthesia (2% lidocaine with 1/100,000epi or 4% articaine with 1/100,000epi). If the patient is willing to receive the surgery under intravenous or oral sedation, those services will be provided based on the necessity. After local anesthesia, intracrevicular incisions will be made and full-thickness mucoperiosteal flaps will be raised both buccally and lingually; the surgeon will try to preserve the maximum extent of the marginal and interdental gingival tissue to obtain primary closure and membrane coverage. Vertical releasing incisions will only be used if necessary to gain access for defect debridement. The alveolar bone will be exposed at least 3 mm beyond the edges of the defect, and periosteal releasing incisions will be made to ensure complete membrane coverage at the time of suturing if necessary. All granulation tissue will be removed, the defects will be debrided, and the roots will be thoroughly scaled and root planed by hand instruments and ultrasonic devices. Following debridement, 17% Ethylenediaminetetraacetic acid (EDTA) solution with cotton pellet will be applied on the root surface for 2 minutes. After thorough irrigation with saline, BioXclude® (Amnion-Chorion Membrane: Food and Drug Administration (FDA) Approved materials for intrabony defects) will be cut into two pieces. The amnion-chorion BioXclude membrane is regulated by the FDA under section 361 of the Public Health Service Act as a "Human cells, tissues, and cellular or tissue-based product" (HCT/P). The FDA does not require pre-market approval for these products like it would with drugs, biologics or devices. Therefore, this product will have no associated "investigational device exemption" (IDE) number. The FDA views using amnion chorion as a wound covering to aid in the healing of tissues throughout the body to be a "homologous use". One goes to the root surface, and coronal portion of the membrane has to be >3mm coronal of CEJ. Once applied the membrane, one drop of saline will be applied to obtain better adaptation of membrane on the root surface. Bone substitutes 0.5cc (Particle size of 0.25-0.5mm of Corticocancellous, Maxxeus®) will be hydrated for at least 10min prior to application, and applied into the defects. The bone particles will not exceed the edge of defects in order to avoid over fill. Following the bone graft will be delivered to the defect. The coronal portion of excessive membrane will be just folded over the graft materials. The other BioXclude membrane will be utilized over the grafts, and will always be placed coronal to the interproximal bone crest so that it completely covers the defect and extends 2 to 3 mm beyond the residual bone. No sutures, pins, or tacks will be used for membrane fixation or stabilization. The orientation of the membrane will not matter. Vertical or horizontal mattress sutures with 5-0 Proline (Monofilament/Nylon) will be placed in the interproximal tissues to obtain primary closure as much as possible.

Intra-surgical Clinical Measurements. Intrabony defects: defect morphology will be measured (1 wall, 2 walls and/or those combinations) from the deepest aspect of the defect from the most coronal side of edge of the defects.

Furcation defects: 1) Cementoenamel junction to roof of furcation (CEJ-ROF); 2) roof of furcation to base of defect (ROF-BOD); 3) roof of furcation to crest of bone at furcation entrance (ROF-COB); 4) crest of bone to base of defect (COB-BOD); 5) root divergence at crest of bone (RDCB); 6) horizontal extent (base) of defect at level of furcation entrance (HBODF); 7) horizontal extent (base) of defect at level of crest of bone (HBOD-C); and 8) cemento-enamel junction to interproximal crest of bone (CEJ-INTPRX)

All patients will receive antibiotics (875mg amoxicillin twice /day) for one week. If participants are allergic to amoxicillin, clindamycin (150mg twice/day) for one week will be prescribed. Analgesics (600mg ibuprofen three times/day) will be prescribed as needed for discomfort. Pt will be seen one, two and four weeks as a post-operative follow up. Patients will be advised to rinse twice daily with 0.12% chlorhexidine for 2 weeks after surgery. Patients will be instructed to refrain from brushing the teeth in the surgical area for 2 weeks. After that, they will be instructed to initiate brushing with an extra-soft toothbrush. Subjects will be recalled at 4-week intervals after 4weeks from surgical procedure for a period of 6 months for plaque scoring, oral hygiene instruction, and professional prophylaxis as needed. No subgingival probing or instrumentation will be performed at the experimental sites until the 6-month follow-up appointment.