Onlay Graft Procedure

To the left above 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 left side (arrow).  To the right above 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 that needs to be filled (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 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 situation, many times we take CT-Scans to verify the actual amount of bone available.

The left image 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 arrow).  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.

To 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 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-Tex 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.  One can already appreciate a noticeable increase in ridge thickness.

Five months after the grafting procedure the patient returns for the implant placement procedure.  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.