A CBCT will be performed to assess the anatomy of the subnasal area and plan the position, size, shape and thickness of the PEEK Stent. These data will be transferred to a 3D planning software to generate a digital model. Eventually, the PEEK stents will be milled in a milling machine and sterilized in ethylene oxide before the surgery. Local anesthesia will be administered into the vestibular mucosa along the extension of the anterior maxilla. VISTA technique begins with a vestibular access incision in the midline frenum and 2 bilateral incisions at premolar area. A periosteal elevator will be introduced through the incision and inserted between the bone and periosteum to elevate the tissue, creating a subperiosteal tunnel, extending distally based on the dynamic of the smile. The PEEK stent will be in one piece. They will be placed onto the bone and stabilized with 2 bone graft screw for each side. The midline incision and the lateral incisions will be sutured primarily.

Distance from gingival margin to lower border of upper lip vermilion border will be measured

evaluated using a 10-point visual analogue scale (VAS; 0 = not satisfied, 10 = highly satisfied)