How To:
Sinus Augmentation with
Membrane Removal and
Implant Placement

With the publication of our technique of removing the sinus membrane during sinus augmentation, we experienced a flood of orders for Sinus Graft. Our previous emails were focused on the success and predictability of the technique, but were not focused on the fine points of the surgery. To help our new customers be successful with the technique, we have compiled a “How to” article to help your decision-making process for what many are calling a game changer for sinus augmentation.

Crestal Approach or Lateral Approach

A CT scan is beneficial to understand the 3-dimensional morphology of the graft site, but it is not necessary to perform this surgery.

The primary decision for this method is if you will use the implant osteotomy to remove the membrane and graft or if you will use a small lateral wall osteotomy to remove the membrane and graft. The preferred choice for surgical expediency is to use the implant osteotomy. However, the decision to use the lateral wall or the crest for your access to the sinus is decided by the amount of bone between the crest and the sinus. If there is 4 mm or less of crestal bone, we recommend using the implant osteotomy to remove the membrane and graft the sinus. If there is more than 4 mm of crestal bone, we recommend using the lateral wall. The reason is because when you are working in bone deeper than 4 mm, it is difficult to get the instruments into the sinus, pivot the instrument around the sinus, and confidently remove the membrane. Likewise, it is difficult to get the tip of the bone graft syringe into a deeper osteotomy and predictably inject the graft material on the floor of the sinus. When using the small lateral wall osteotomy, it is easy to remove the membrane from the floor of the sinus and easy to inject the graft material onto the floor of the sinus.

Due to the ease of instrument manipulation, we advise those new to the technique to use the lateral wall method. The sinus membrane is very delicate and there is no need to vigorously scrape the sinus wall. There is no need to remove any bone and no need to create bleeding. If you create any bleeding, you are scraping too excessively. If using the lateral wall method, make crestal incisions in the gingiva and on the buccal, carrying the incisions around the mesial of the anterior tooth. Make a vertical incision on the distal line angle of the tooth anterior to the tooth adjacent to where the implant will be placed. Raise the flap to gain access to the lateral wall of the sinus. No distal vertical incision is usually needed. Do not raise the lingual flap until you have grafted and you need to start your implant osteotomy. This is to prevent bleeding into the patients mouth while working on the buccal. The reason for carrying the vertical incision further away from the lateral wall osteotomy is so you do not have a vertical incision near the lateral osteotomy. The small osteotomy will heal spontaneously and will not need a membrane. After you have made your flap, mix Sinus Graft. You will need to let the graft activate for about 3 minutes before use, but as long as the graft is in the syringe, it will not set even though it is mixed. Use sterile gauze to pick up the syringe tip so no bacteria is carried into the sinus.

When locating where to place the lateral wall osteotomy, simply measure the amount of bone between the crest and sinus and add a few more millimeters above the radiographic location for the floor of the sinus. Because you are going to remove the sinus membrane, simply drill through the lateral wall and into the sinus with a large round bur. Enlarge the osteotomy to approximately 4 mm. Once into the sinus, it is good to get a feeling for the difference between the feel of the sinus membrane and bone. Use a blunt instrument (probe or ball burnisher) to enter the sinus and you will note that the membrane has a velvet feel to it. This will help you know that the membrane is removed because bone will have a grainy feel to it. Once you are into the sinus, either through the implant osteotomy or a lateral osteotomy, we start our membrane removal with an angled curette and finish with a hoe such as a 13K. We use these instruments simply because they are always on our surgical tray. If there are any enterprising dentists reading this: custom designed curettes for sinus membrane removal could be an advantage.

Estimate the amount of bone you need to produce on the floor of the sinus and remove the membrane to at least this distance. The bone graft will bond to bone, but not to the sinus membrane. Where you have membrane, you will not get bone growth.

If you are doing a lateral wall approach, lay the lingual flap and prepare your osteotomy for the implant after you have grafted the sinus. If there has been significant time lapse since placing the graft, possibly due to placing multiple implants, you will want to prepare your implant osteotomy to the full length of the implant. The graft may have hardened and placing an implant into hardened graft can lift the graft off the floor of the sinus. Sinus Graft sets in about 30 minutes once applied into the sinus.

Let’s look at some cases that explore these points.
With approximately 4 mm of crestal bone, the decision is made to graft through the implant osteotomy.
The flap is raised and the membrane is removed first using an angled curette.
After use of the angled curette, a 13K is used to ensure the removal of the sinus membrane.
When grafting through the implant osteotomy, place the syringe tip into the osteotomy and direct the syringe tip toward the lateral walls of the sinus. Rotate the syringe as you inject. This will place the graft material into the floor of the sinus. Inject the 2 cc of graft material where bone regeneration is needed. After injecting the graft material, take a radiograph to confirm placement. If voids are noted, inject another 2 cc syringe into that site.

In this case, voids appear on the floor of the sinus and distal to the osteotomy. A second syringe is prepared and these areas are re-grafted for a total of 4 cc.

Day of surgery with graft complete and implant in place.
Two weeks post-op implant placement.
The graft material is still evident. The graft material will become radiolucent as cells and the vascular supply enter the graft.
3 months post-op, the implant is integrated and the healing abutment is placed and prepared for restoration. Do not expect to see the dense radiopaque sclerotic bone as you see with cadaver bone grafts. The radiopacity seen with cadaver bone grafts is largely due to the mineralization of the residual graft material rather than new bone. When using Sinus Graft, all of the graft material has been resorbed after three months and all of the radiopacity is due to new bone formation. When the implant is loaded, the bone in the sinus will remodel from woven to lamellar bone and the density will increase.

#6 was extracted with complete loss of the buccal wall. #6 was extracted and grafted with Socket Graft Plus and covered with a d-PTFE membrane. At 4 weeks post extraction, the membrane was removed.

11 weeks after extraction of #6.
The patient presents for sinus augmentation and implant placement of #4 and #6 for an implant-supported bridge.
Because there was approximately 6-7 mm of crestal bone, a lateral wall osteotomy was chosen for access to the sinus for membrane removal and grafting.

The sinus membrane is removed and the floor of the sinus is filled with Sinus Graft. The implants are placed. However, a minimal amount of bone exists buccal to #4.

To augment the buccal wall for #4, Socket Graft Plus is grafted over the buccal ridge. In this case, where only a few millimeters of buccal bone is needed to protect #4, no membrane is used to cover the graft. Also, note that in the area of complete loss of the buccal wall of #6, the buccal wall is regenerated with normal healthy vital bone.
Day of surgery
Two week post op. The granular material appearing on the floor of the sinus (arrows) is not in the sinus, but are βTCP particles on the buccal of the maxilla used to augment the buccal ridge.

Implants are restored and have been in function for a few months. This image is 7 months post grafting and implant placement. Bone is at the coronal edge of the implants and bone fills in the sinus. The area of ridge augmentation over the floor of the sinus, as previously noted, continues to remodel as the βTCP particles are resorbed in the newly formed buccal bone.

7 months post implants with implants restored. Good healthy keratinized gingiva with augmented ridge providing good buccal implant support.
We have covered two typical cases where in the one case a crestal osteotomy is preferred and another case where a lateral wall osteotomy is preferred. However, in some cases, chairside judgement is called for as we discuss in the following case.
Failing molar with extreme pneumatization of the maxillary sinus extending between the roots of #14. At the time of extraction, a significant perforation into the sinus was noted.
Day of surgery, 3 months after extraction. Radiographic healing is questionable; sinus augmentation and implant is planned.
Crestal flap exposes deficient crestal healing with soft tissue communication with the sinus. The decision made was to extend the buccal flap reflection and access the sinus with a lateral window approach.
The crestal defects are debrided of soft tissue and the sinus membrane is removed.
A radiographic confirmation shows the fill of the sinus using Sinus Graft.
After the sinus is grafted, the implant is placed.

The crestal defects are grafted with Socket Graft Injectable.

A membrane is not needed for the buccal osteotomy, but due to the proximity of the crestal defects to the crestal incision lines, a d-PTFE membrane is placed.
Day of surgery complete.
Two weeks post-op.
4 weeks post-op.
4 months post-op showing the sinus fully mineralized.
Healing abutment placed at 4 months and referred for restoration.
When using Sinus Graft, all implants are placed simultaneously with grafting irrespective of the amount of crestal bone. Because integration has been proven to occur to the implant surface as the graft material is being converted to bone delayed implant placement is not indicated. In routine sinus augmentation surgeries, the time period from grafting and implant placement and restoration is 3 months. However, in this case with significant crestal defects, restoration was timed at 4 months. When only 1 to 2 millimeters of crestal bone is present at the time of grafting and implant placement, the 4-month healing time period is also advised.

SteinerBio continues to innovate surgical techniques and develop bone graft materials that allow the clinician to stay in the forefront of current technology. With the advent and innovated use of science-based bone graft materials, sinus augmentation can now leap past the sinus membrane for simple, easy and predictable implant placement in the maxillary posterior dentition.


American Society for Bone and Mineral Research (ASBMR)

Tissue Engineering and Regenerative Medicine International Society (TERMIS)