When upper back teeth are lost, the resulting bone loss can complicate the placement of dental implants. The maxillary sinuses, located above the molars and premolars, often expand into the space once occupied by the roots of these teeth. This expansion, combined with natural bone resorption, may leave insufficient bone height for implant support. A sinus graft is a surgical procedure that solves this problem by adding bone below the sinus cavity to create a stable foundation for dental implants.
At Montana Center for Implants and Dentures, sinus grafting is offered to help patients with bone loss in the upper jaw restore both function and aesthetics through successful implant placement. This article explains what a sinus graft is, why it is performed, the procedure involved, and how it supports long-term oral health.
What Is a Sinus Graft?
A sinus graft, also called a sinus lift or sinus augmentation, is a surgical technique used to increase the amount of bone in the upper jaw beneath the sinus cavity. The goal is to provide adequate vertical bone height to support a dental implant. The procedure involves gently lifting the sinus membrane and inserting bone graft material into the space created.
According to a comprehensive review in the International Journal of Oral and Maxillofacial Implants, sinus augmentation procedures have a high success rate, with implant survival rates of over 90% when combined with well-planned implant treatment. The same review notes that sinus grafts are among the most predictable bone grafting procedures in implant dentistry.
Why Sinus Grafts Are Necessary for Dental Implants
Dental implants require stable bone to integrate properly. This process, called osseointegration, involves the fusion of the implant post with the surrounding bone. Without sufficient bone height or density, implants cannot be safely placed or may fail prematurely. In the upper jaw, particularly in the area of the molars and premolars, the proximity of the maxillary sinus often limits bone availability.
Tooth loss accelerates bone resorption in the jaw. Studies indicate that the alveolar ridge can lose up to 60% of its width and height within three years following extraction. In the posterior maxilla, this is compounded by sinus pneumatization—a natural process in which the sinus cavity expands, further reducing bone height.
When a patient seeks dental implants in this area, the combination of bone resorption and sinus expansion may leave only 4–5 mm of bone, while most implants require at least 10 mm for stability. This is where the sinus graft becomes essential.
Candidates for Sinus Grafting
Patients who may benefit from a sinus graft typically exhibit one or more of the following conditions:
- Missing upper molars or premolars for more than a few months
- Severe bone loss in the posterior maxilla
- Naturally large sinus cavities
- Prior denture use that has contributed to bone loss
- History of periodontal disease in the upper jaw
At Montana Center for Implants and Dentures, patients undergo a full diagnostic assessment using 3D cone beam computed tomography (CBCT) scans to evaluate sinus anatomy and bone volume. This precise imaging allows the surgical team to determine whether a sinus graft is necessary and which approach will be most effective.
The Sinus Graft Procedure
There are two main techniques for sinus grafting: the lateral window approach and the transcrestal (osteotome) approach.
Lateral Window Technique
This method is used when there is less than 5 mm of bone height. A small window is created in the lateral wall of the maxillary sinus, the sinus membrane is gently elevated, and bone graft material—often a mixture of autogenous bone, donor bone, or synthetic substitutes—is placed in the newly created space. Over the next 4–9 months, the graft material integrates with the patient’s natural bone.
Transcrestal Technique
Also known as the osteotome technique, this is a less invasive approach used when at least 5–6 mm of bone is already present. The sinus membrane is accessed through the same opening created for the dental implant. This method may allow for implant placement during the same surgical procedure.
The decision between these methods depends on bone availability, the patient’s medical history, and the overall treatment plan. Both procedures are typically done under local anesthesia with or without sedation and are performed on an outpatient basis.
Healing and Integration
Following a sinus graft, patients are advised to avoid activities that increase sinus pressure, such as forceful nose blowing, heavy lifting, or flying, for a few weeks. Mild swelling or nasal congestion is normal and typically resolves within a few days.
The grafted area requires time to heal and integrate with the existing bone. This process generally takes 4 to 9 months, depending on the extent of the graft and the patient’s individual healing response. Once sufficient bone volume is achieved, dental implants can be safely placed and restored.
A study published in Clinical Oral Implants Research reported implant survival rates of 92–98% in grafted sinus areas, comparable to implants placed in native bone. This demonstrates the long-term viability and effectiveness of sinus augmentation procedures.
Benefits of Sinus Grafting
The primary benefit of a sinus graft is that it enables patients who were once ineligible for dental implants to receive them successfully. But there are additional advantages that extend beyond the immediate restoration:
1. Improved Oral Function
By making implant placement possible, sinus grafts support the restoration of natural chewing ability. This improves digestion and nutrition, as patients can comfortably eat a wider variety of foods.
2. Bone Preservation
The addition of bone graft material prevents further bone loss in the posterior maxilla, which can otherwise continue unchecked after tooth loss.
3. Enhanced Facial Support
Rebuilding the upper jaw helps preserve facial structure, reducing the sunken or aged appearance that often accompanies significant bone resorption.
4. Long-Term Stability of Dental Implants
Implants placed in augmented sinuses have a similar success rate to those placed in dense, healthy bone, meaning patients can expect long-lasting, stable results.
5. Support for Oral Health
A stable, well-supported restoration minimizes the shifting of remaining teeth and promotes better long-term oral health. Poorly fitting dentures or bridges can accelerate bone loss and tissue damage; implants supported by sinus grafts avoid these issues.
Risks and Considerations
As with any surgical procedure, sinus grafting carries some risk, though complications are relatively rare. These may include:
- Perforation of the sinus membrane (most common complication, but usually manageable)
- Infection or sinusitis
- Graft rejection (uncommon with modern materials and techniques)
- Swelling or bleeding
Patients are carefully screened before the procedure, and pre-existing conditions like chronic sinusitis or uncontrolled diabetes are addressed to reduce risk. At Montana Center for Implants and Dentures, post-operative care and follow-up imaging help ensure proper healing and graft integration.
How Sinus Grafting Fits into a Comprehensive Dental Implant Plan
Sinus grafting is not a standalone treatment. It’s one component of a carefully sequenced plan to restore missing teeth with dental implants. In some cases, the sinus graft is done months before the implant is placed. In others, when bone height allows, it can be performed at the same time.
The planning process includes:
- Comprehensive oral exam
- CBCT imaging
- Medical and dental history review
- Evaluation of sinus anatomy
- Bone density and height measurement
- Customized treatment sequencing
This structured approach ensures that implants placed in the upper jaw have a solid, lasting foundation.
The Montana Center for Implants and Dentures Approach
At Montana Center for Implants and Dentures, our team offers a full range of implant-related procedures, including sinus grafting, under one roof. This reduces the need for outside referrals and keeps your care streamlined and consistent.
Dr. Josh Muir and Dr. Tanner Townsend use advanced diagnostics and precision surgical techniques to deliver outcomes that meet both functional and aesthetic goals. Whether you’re missing a single molar or need a full upper arch reconstruction, our team will determine whether a sinus graft is needed to support your long-term oral health.
We understand that the idea of a sinus graft can sound intimidating, but our patients frequently report minimal discomfort and high satisfaction with the outcome. Most importantly, the procedure opens the door to implant treatment for individuals who might otherwise be told they aren’t candidates.
Final Thoughts
A sinus graft is a powerful tool in implant dentistry that makes it possible to rebuild the upper jaw and support stable, long-lasting dental implants. When performed correctly, it enhances both functionality and aesthetics while protecting long-term oral health.
At Montana Center for Implants and Dentures, we take the time to evaluate each case individually. If you’re missing upper back teeth and have been told that implants aren’t possible due to bone loss, a sinus graft may be the key to restoring your smile and your confidence.
If you’re ready to explore whether this treatment is right for you, contact our team today to schedule a consultation. We’ll walk you through every step of the process and help you make a decision based on your goals, health, and long-term success.
Sources
- Wallace, S.S., Froum, S.J. “Effect of Maxillary Sinus Augmentation on the Survival of Endosseous Dental Implants.” Clinical Oral Implants Research, 2003.
- Chan, H.-L., et al. “Long-term outcomes of sinus augmentation: A systematic review.” Journal of Clinical Periodontology, 2014.
- Jensen, O.T. The Sinus Bone Graft. Quintessence Publishing, 2006.
- Misch, C.E. Contemporary Implant Dentistry, 3rd Edition. Mosby Elsevier, 2008.
