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Fundamentals of Esthetic Implant Dentistry
tissue around the rim of the extraction socket is then deepithelialized with a diamond bur or a sharp scalpel. A wide diameter trephine drill that is larger than the diameter of the socket orifice is used to harvest the composite graft from the tuberosity. A slow-speed, high-torque handpiece with copious internal and external saline irrigation should be used during the harvesting procedure to avoid overheating the graft. A green stick fracture of the composite graft is performed at its base to separate it from the donor site. Here, caution must be used not to perforate the maxillary sinus; a preoperative X-ray film or digital imaging can help determine the extent of drilling needed. The keratinized layer of the graft core is then peeled with a sharp scalpel to remove only the surface epithelium, leaving almost 3 mm of connective tissue attached to the bone core. If the bone core is found to be larger than the socket orifice, it should be pared so that it will fit snugly in the socket. The apical third of the extraction socket is subsequently filled with demineralized freeze-dried bone and a puffy coat containing PDGF. Afterward, the composite graft is introduced into the socket and tapped gently into place using a mallet and a blunt instrument. Upon seating, the surface of the composite graft should conform to and be level with the crestal contour of the socket; it may be positioned slightly below the surrounding marginal gingival. This is to allow for epithelial migration from the sides of the socket on top of the connective tissue graft. The connective tissue portion of the graft is then sutured to the surrounding gingival tissues. A provisional removable prosthesis should not be allowed during the first few weeks after surgery when this technique is used, because the composite graft may move upon pressure and become sequestrated due to premature loading of the bone that results from fitting the surface of the prosthesis. The osteotomy hole of the donor site can be filled with any bone-grafting material or heavily packed with collagen sponge. Primary wound closure can be achieved by undermining the soft tissue edges, or preferably, an acrylic template may be used to seal the area of the defect until it heals by secondary intention. This technique reduces the risk of morbidity, because the quality of the bone harvested from the tuberosity offers the best environment for blood circulation and bone formation in its wide cancellous compartments. A fair enhancement of the soft tissue quality and quantity over the socket is also offered (it attains the exact color and texture of the surrounding tissues). It also offers faster and more predictable bone regeneration inside the socket, thus improving the overall prognosis for any future implant placement. (See Figures 5.6A–G.)
A Figure 5.6A. Sever gingival recession with accompanied bone loss that mandates clinical management.
B Figure 5.6B. The two involved teeth have been removed and replaced with two dental implants in immediate placement.
C Figure 5.6C. The removed natural crowns have been prepared to act as provisional crowns for the implants (non-functional immediate loading).