Subperiosteal Dental Implants for Severe Bone Loss

A subperiosteal implant is a custom-made metal framework that sits on top of the jawbone, just beneath the gum tissue, rather than being drilled into the bone the way conventional dental implants are. Originally popular from the 1940s through the 1980s, this implant type fell out of favor when screw-shaped root-form implants proved more predictable over the long term. But advances in 3D imaging and metal printing have brought subperiosteal implants back into serious clinical use, particularly for patients whose jawbones have wasted away so severely that standard implants simply cannot anchor into them.

How Subperiosteal Implants Differ From Conventional Ones

Standard dental implants are endosseous, meaning a surgeon drills a hole into the jawbone and threads a screw-like post into it. Bone then grows directly onto that post over several months. That approach works well when there is enough bone height and width to hold the screw. When the bone has resorbed to the point where there is almost nothing left to drill into, the usual solution involves bone grafting, sinus lifts, or other rebuilding procedures that can span many months and multiple surgeries before an implant is ever placed.

A subperiosteal implant bypasses the bone-volume problem entirely. Instead of going into the bone, a lightweight metal framework is shaped to rest on the bone’s surface. Small titanium screws pin the framework in place, and posts protrude through the gum tissue to support a fixed set of replacement teeth. Each implant is passively adapted to the bone and secured with titanium osteosynthesis screws to achieve primary stability, meaning the framework does not rely on the bone’s density for initial rigidity.¹ Because the prosthetic teeth can often be attached within days rather than months, many patients walk out of surgery with functioning teeth almost immediately.

Why They Disappeared and Why They Came Back

Subperiosteal implants were a go-to option for patients with severely wasted jaws from roughly the 1940s through the 1980s. Then the Brånemark osseointegrated implant arrived and changed everything. Root-form implants had more favorable and predictable long-term outcomes, and subperiosteal designs quickly dropped out of fashion.² The old versions had real problems: they were cast from impressions taken directly on exposed bone during surgery, which was imprecise and traumatic. Bacterial colonization of the framework caused reactive bone loss, infections, hardware exposure, and pain, and many implants had to be removed altogether.

What changed over the past decade is digital technology. Cone-beam computed tomography (CBCT) scans now let clinicians map a patient’s jawbone in three dimensions long before surgery, and computer-aided design paired with metal 3D printing produces a framework that fits the bone surface with a level of precision that casting from a surgical impression never achieved.³ The entire design and manufacturing process happens digitally, reducing patient trauma and allowing the surgeon to rehearse the placement virtually.⁴ The framework is then printed in medical-grade titanium using a laser sintering process and arrives sterile and ready to place. Surgery becomes a single procedure instead of a multi-stage ordeal.

Who Is a Candidate

The primary audience for subperiosteal implants is people with severely atrophic jaws, meaning the jawbone has shrunk so much that standard implants cannot be placed without extensive grafting. This includes patients who have been edentulous (completely toothless) for years or decades, patients whose previous implant-supported restorations have failed due to bone loss, and patients with congenital conditions that prevented normal jaw development.

One case report describes a 44-year-old man with congenital dental agenesis whose earlier all-on-six implant restoration had failed because of peri-implantitis. He was successfully treated with custom subperiosteal implants in both jaws, combining subperiosteal and endosseous support in a single-stage procedure with immediate loading.⁵ Another report details a 23-year-old woman with EEC syndrome, a rare craniofacial condition, who had undergone multiple bone-grafting procedures that still left her unable to receive conventional implants. A custom subperiosteal implant remained stable at 18 months with no complications.⁶

In one institutional case series, eight patients with the most extreme category of maxillary bone loss (Cawood and Howell class VI) were treated with patient-specific subperiosteal implants.⁷ These are patients who, without this option, might face repeated grafting surgeries or be left with removable dentures that fit poorly on a flat, shrunken ridge.

Survival Rates and Clinical Performance

The modern evidence, though still limited to relatively short follow-up periods, is encouraging. A systematic review of additively manufactured subperiosteal implants found that after a weighted mean follow-up of about 21 months, roughly 98% of implants were still in function, with five failures reported across the included studies.⁸ A separate study following 16 patients with 21 custom subperiosteal implants for a median of three years reported implant survival and success rates of about 95% at both the one- and five-year marks, with negligible bone resorption beneath the abutments.

A longer-term analysis using Kaplan-Meier methods found a survival rate of roughly 97% and a success rate of about 92% after the first two years. When researchers tracked the implants for nearly nine years, however, the success rate dropped to around 54% and survival to about 89% when stricter criteria were applied that counted any complication needing intervention as a failure.⁹ Those numbers deserve context: many of the “failures” involved manageable mechanical issues like provisional restoration fractures rather than total implant loss, and the patient population included complex cases that would challenge any implant system.

Complications to Know About

The most commonly reported issue is partial exposure of the implant framework through the gum tissue. In the systematic review mentioned above, about a quarter of implants showed some degree of exposure.¹⁰ That sounds alarming, but many exposures remain asymptomatic and manageable with good hygiene. Still, when gum tissue recedes enough to reveal the metal framework, bacteria can colonize the surface and cause infection. About 5% of patients in that same review developed soft tissue infection or persistent infection requiring treatment.

A scoping review of CAD/CAM subperiosteal implants broke complications into two categories: biological complications like wound dehiscence, bone loss, and implant exposure occurred at a rate of about 4%, while mechanical complications such as provisional restoration fracture, instability, and crown re-cementation occurred at about 7% over follow-up periods of one to four years.¹¹ Many of the mechanical issues involved the temporary prosthesis cracking before the permanent one was fabricated, which is a nuisance more than a crisis.

The historical failure mode that killed the original subperiosteal implants, where bacteria worked their way down the posts and colonized the entire substructure, still represents a theoretical risk with the modern designs. But the improved fit from digital design, along with surface treatments on the titanium framework, appear to have reduced this substantially. Researchers acknowledge that true long-term data beyond five years remains limited for the digitally manufactured versions.

Subperiosteal Versus Zygomatic Implants

When a patient’s upper jaw is too wasted for standard implants, the two main alternatives that avoid bone grafting are subperiosteal implants and zygomatic implants. Zygomatic implants are very long screws (sometimes 50 mm or more) that anchor into the cheekbone instead of the jaw. They have decades of data behind them, but the surgery is aggressive, and complications tend to involve the sinuses.

A five-year comparative study found that survival rates were statistically similar between the two: about 96% for zygomatic and 97% for subperiosteal implants. The difference lay in the complication profiles. Zygomatic implants had sinus-related complications in about 12% of cases and carried risks of orbital damage, while subperiosteal implants showed peri-implantitis in about 6% of cases with better soft tissue stability overall.¹² Interestingly, that study also found that surgical time was actually shorter for subperiosteal implants (averaging about two hours versus roughly three for zygomatic). One practical advantage of subperiosteal designs is that if the implant does fail, it can be removed and replaced, an option that is difficult or impossible with zygomatic implants because the cheekbone pathway cannot easily be reused.

A systematic review comparing the two approaches in the context of graftless rehabilitation echoed similar findings: zygomatic implants showed survival rates around 96% but with sinusitis as a recurring complication, while subperiosteal implants reached about 98% survival with fewer complications when CAD/CAM technology was used, though with shorter follow-up data available.¹³

What Happens to the Bone Underneath

A reasonable concern is whether placing a metal framework on top of bone causes it to deteriorate further. The evidence so far is reassuring. One animal study found that all 18 subperiosteal implants tested were completely osseointegrated, meaning bone actually grew into and around the framework rather than receding from it.¹⁴ In the clinical series following patients for a median of three years, radiological assessments showed negligible bone loss beneath the abutments, averaging less than 0.2 mm at one year.

Biomechanical modeling helps explain why. Finite element analysis, which simulates how forces distribute through structures, has shown that subperiosteal implants spread chewing forces more evenly across the bone surface than conventional implants, reducing the stress peaks that can trigger bone loss at the implant-bone interface.¹⁵ Framework thickness matters: thicker designs (around 2 mm) produced lower stress on the underlying bone than thinner ones (1 mm), because the thinner framework flexes more under load and concentrates pressure.¹⁶ Oblique biting forces, like those generated when chewing on one side, increased displacement risks more than straight vertical loading, which is one reason clinicians pay attention to prosthetic design and bite balance.

Titanium Versus PEEK

Almost all modern subperiosteal implants are printed in titanium alloy, but a polymer called PEEK (polyether ether ketone) reinforced with carbon fiber is gaining attention as an alternative. Titanium is the gold standard for biocompatibility and strength, but it is much stiffer than bone, which raises concerns about stress shielding, where the implant bears so much of the load that the underlying bone atrophies from disuse.

A finite element study comparing titanium and 60% carbon-fiber-reinforced PEEK subperiosteal implants found that while the stress values within the titanium framework itself were roughly twice those in the PEEK version, the stress transmitted to the cortical and spongy bone was nearly identical between the two materials.¹⁷ That suggests PEEK could function as a viable alternative without disadvantaging the bone. A small clinical trial randomly assigned ten patients to receive either porous titanium or PEEK subperiosteal implants. At 12 months, all implants in both groups were functionally stable with no signs of bone loss, mobility, infection, or prosthetic fracture, though one titanium case had wound dehiscence.¹⁸ PEEK also does not produce the metallic artifacts on CT scans that titanium does, which can be an advantage for ongoing monitoring.

How Teeth Get Attached

One of the biggest practical selling points is speed. Because the framework sits on the bone rather than needing to integrate into it before bearing load, many protocols allow provisional teeth to be screwed onto the abutments within 48 hours of surgery.¹⁹ Patients leave the hospital with a temporary fixed bridge that allows them to eat soft foods and function socially while healing progresses. A permanent prosthesis is typically fabricated several months later once the tissues have fully matured.

The impact on quality of life is measurable. A prospective multicentre study tracked patient-reported outcomes using a standardized oral health questionnaire. Before surgery, patients scored an average of about 17 on a scale where higher numbers indicate worse oral health impact. By one year, that score had dropped to about 5, a statistically significant improvement that reflected better chewing ability, comfort, and confidence.²⁰

Applications Beyond Routine Jaw Atrophy

Clinicians are increasingly exploring subperiosteal implants for patients whose jaw defects go well beyond typical age-related bone loss. In oncology, patients who have had parts of their jaw removed during cancer surgery face enormous reconstructive challenges. One reported case involved a 59-year-old man who underwent total maxillectomy for squamous cell carcinoma of the hard palate. Surgeons combined a fibula free flap (bone and tissue transplanted from the leg) with a custom 3D-printed subperiosteal implant that provided a stable framework for prosthetic teeth. Two years after surgery, the patient was disease-free with a fully functional prosthesis and no complications.²¹

These oncological applications represent a frontier where few other implant options exist. After large jaw resections, the remaining anatomy is often so distorted that standard implants, zygomatic implants, and even extensive grafting cannot reliably provide prosthetic support. The ability to digitally design a framework that conforms to whatever bone anatomy remains, however irregular, is what makes subperiosteal implants uniquely suited to this challenge.

Keeping the Implant Healthy Long Term

Maintenance protocols for subperiosteal implants are still being formalized, partly because modern versions have not been in widespread use long enough to generate extensive long-term hygiene data. A narrative review on the topic concluded that professional maintenance needs to be tailored to each patient’s prosthetic complexity, the accessibility of the parts that pass through the gums, tissue condition, and whether any areas of the framework are exposed. The goal is to disrupt bacterial biofilm without traumatizing the soft tissue or scratching the implant surface. Air polishing with low-abrasion powders like glycine or erythritol has been suggested as a minimally invasive option for keeping biofilm under control.²²

At home, patients generally follow a regimen similar to what anyone with implant-supported fixed teeth would use: soft interdental brushes to clean around the abutments, possibly a water flosser, and regular dental visits. Because partial framework exposure is common, some patients have areas of metal visible along the gum line that require extra attention to prevent plaque accumulation.

Regulatory Hurdles for Custom 3D-Printed Devices

Every subperiosteal implant is a one-off, designed and printed for one specific patient’s anatomy. That creates a regulatory puzzle. Traditional medical device approval processes assume standardized products that can be tested in batches, but a custom implant is inherently a batch of one. Regulatory bodies have had to grapple with how to ensure quality when the design changes with every patient. Consistent material powder properties, printing parameters like build orientation and laser power, and post-printing steps such as cleaning, finishing, and sterilization all need to meet strict standards and be documented for each build.²³

In practice, most subperiosteal implants are currently provided under frameworks for patient-specific devices or compassionate use pathways rather than as off-the-shelf cleared products. This means availability depends heavily on geography: some countries have clear pathways for custom-printed medical devices while others require case-by-case approval. Patients interested in this option typically need to be treated at specialized centers with in-house or partnered digital manufacturing capabilities. As the evidence base grows and manufacturing processes become more standardized, broader regulatory clearance may follow, but for now the technology sits in a somewhat liminal space between experimental and mainstream.

What the Cost Picture Looks Like

Precise cost data comparing subperiosteal implants to alternatives are scarce in the literature, partly because the technology is still niche and pricing varies widely by region and facility. What can be said is that the digital design and 3D printing process is expensive on its face. A CBCT scan, digital design by a specialized engineer, titanium powder, and laser sintering all carry costs that do not apply to a standard implant placement. However, the overall treatment cost needs to be weighed against what the alternative pathway involves: bone grafting (which may require donor-site surgery), months of healing, multiple surgical stages, and sometimes repeated attempts when grafts fail. For a patient who would otherwise need three or four surgeries over 12 to 18 months before a single implant screw goes in, a one-stage subperiosteal procedure with immediate teeth may actually prove competitive on total cost and is unquestionably faster. The economic argument becomes stronger as digital manufacturing costs continue to fall and clinical workflows become more streamlined.