Clinical and Radiographic Evaluation of Bone Gain Using Customized 3D Printed Zirconia Barrier Versus Titanium Mesh in Combined Ridge Defects in The Aesthetic Zone: A Randomized Clinical Trial

After a tooth is extracted, the alveolar process undergoes an inevitable dimensional change as part of the post extraction remodeling process. The alveolar process is reduced both in the vertical and the horizontal dimension. Therefore, Bone augmentation procedures have been employed to address this issue. A number of bone grafting materials and membranes have been used including resorbable and non-resorbable membranes. It is well-established that non-resorbable membranes produce greater bone augmentation than resorbable ones in terms of their ability to generate new bone. However, their complications make them a less popular option in everyday clinical practice.

Zirconia surfaces show prominent osteo-conductivity, also it has low affinity to bacterial plaque, small amounts of inflammatory infiltrate and good soft-tissue integration. Therefore, this study aims to introduce customized-3D zirconia barriers as a predictable alternative to titanium mesh with horizontal bone gain used as primary outcome.

A randomized clinical trial designed to evaluate the amount of bone gained clinically and radiographically using customized 3D printed zirconia barrier compared to titanium mesh with 26 sites with combined ridge defect total sample size, 13 sites per arm. Once patient preparation is completed and the radiographs are acquired, the patient will be assigned into an arm in the study to allow for barrier manufacturing.

For the zirconia group from the pre-operative CBCT a 3D model of the alveolar jawbone will be created. A 0.4-0.5 mm-thick barrier will then be designed. It will be designed to cover the planned bone graft and extended a few millimeters wider than the graft perimeter. The barrier will be milled and sintered, after milling and finishing, the zirconia meshes will be cleaned, dis-infected and sterilized. At the time of the surgery and after administration of anesthesia, the full thickness flap of the atrophic area will be elevated adjacent to the defect site. Autogenous bone particulate will be harvested. Autogenous bone will be harvested by using an auto-chip maker (ACM) bur, autogenous bone chips that collected with ACM bur will be mixed with a xenograft at 50:50 ratio. A try-in of the barrier will be performed before grafting the area to verify whether its adaptation to the recipient site will be correct. A part of the graft will be placed into the atrophic area and the other part of it was placed into the inner side of the barrier. The barrier will be then placed and according to the clinical situation, two or three fixation screws were tightened at 10 N/cm.

The titanium mesh group, an aluminum foil will be adapted to the defect site and used as a guide for trimming the titanium mesh and ensure its adequate fit. The titanium mesh will be polished to prevent dehiscence or premature exposure. It will then stabilize over the particulate graft by 2 mm titanium mini screws at the labial and palatal sides. Releasing incisions of the flaps will be the next step in the procedure. Then, suturing was performed with single and horizontal mattress sutures.