Onlay Grafting...the following images are very graphical

This collection of images goes through a typical Onlay Graft procedure. This procedure is widely used to treat resorbed bony ridges of the upper or lower jaw. This is usually necessary prior to implant placement in order to insure proper positioning of the implant and better esthetics of the future prosthesis.

To the left you can see a transverse-sectional CT-Scan image of the patient’s upper jaw. Notice how thin the ridge is on the patient’s right side (arrow). To the right you can see a picture of the patient’s upper jaw in a stone cast copy. A Surgical Template is placed over the toothless area to simulate where the actual replacement teeth should be, assuming proper occlusion (bite) and esthetics. Notice the space we need to fill (arrow) in order to create enough room for implants.

The left image shows the pre-surgical condition intraorally. The clinical picture actually does not look too bad in terms of ridge width, however once we open the area up and reflect the soft tissues somewhat, as is shown above on the right, you can appreciate how thin the ridge actually is (arrow). In this case the thick layer of soft tissues (gums) masked the thin bony ridge. Since looks can often be deceiving in these situations, we often take CT-Scans to verify the actual amount of bone available.

The left image above shows the bony ridge exposed with the surgical template in place. This will guide us during surgery as to how far we have to graft the area out (notice the discrepancy as shown by the marker). The two blue double arrows also show the thickness of the tissues in relation to that of the ridge. For this amount of bone needed, we selected the patient’s chin as an appropriate donor site. The picture on the right shows the chin bone exposed.

The image on the right shows the pieces of bone that are going to be transferred from the chin to the upper jaw. The attachment screws are already inserted. The right image shows the chin with the bone pieces removed. You can actually see that we removed all the bone marrow with the graft, since we have only the cortical portion of the other (lingual) side left.

Above the left you can see the bone pieces ready to be transferred to the upper jaw and to the right is a picture of the donor site being treated with a collagen-type material (AviteneÒ), in order to achieve quick hemostasis. After that the mentalis muscle of the chin is re-sutured and re-suspended with resorbable sutures and then the incision is re-sutured to close the wound.

The left image above shows the bone pieces attached to the upper jaw, so that the width of the ridge can be increased. Once the Onlay Graft pieces are firmly attached, the voids are filled in with some ground autogenous bone and sometimes the whole area is covered up with a Gore-TexÒ Membrane. After that the tissues are re-approximated and sutured as you can see on the right.

The donor site is closed and sutured as described above (left). The post-operative complications are usually minimal with this procedure. On the right you can see the upper jaw after 8 weeks of healing.

Five months after the grafting procedure the patient returns for the implant placement. To the left you can see the patient’s upper jaw five months after the grafting procedure, with the original surgical template in place. Notice how we achieved to fill the defect as it was shown above, prior to the grafting procedure. Once we reflect the tissues, you can see the width of bone we gained as compare to the pre-op picture above (right image).

This allows us to place the implants in the right spot to satisfy our pre-established functional and esthetic parameters. To the left you can see the implants placed into the previously grafted area.

Although this procedure is widely used today with great success, we are constantly trying to improve and facilitate grafting procedures for the patient as well as for the surgeon. Concepts like Distraction Osteogenesis may eventually replace many Onlay procedures. This process, in isolated situations, can achieve similar results as the Onlay Grafting procedure within 8 weeks without the necessity of a donor site. Once we have enough confidence in this procedure, it will find its way to this web site.