Zygomatic Implants

What Are Zygomatic Implants?

Zygomatic implants are long implants used when the upper jaw has lost too much bone to hold a standard implant. A standard implant sits inside the jawbone; a zygomatic implant is placed from inside the mouth and anchors its tip in the cheekbone (zygoma). The support for a fixed bridge then comes from the cheekbone, which is not affected by tooth loss, rather than from the upper jaw bone that has shrunk after the teeth were lost.

The method exists as an alternative to bone augmentation. A Cochrane review describes zygomatic implants as a way to place implants in a severely resorbed upper jaw without bone grafting and to fit a fixed bridge early; the same review notes that the procedure is technically demanding and may be associated with serious complications (PubMed 42489150). Those two points sum up the treatment: a shorter route, but a more involved operation.

A zygomatic implant is not a tooth on its own but part of a bridge plan. In most cases it carries a fixed bridge for the whole upper jaw that is screwed onto the implants and that you do not remove yourself. Where the bone can hold four or six implants, the same goal is met with full mouth dental implants, and one or a few missing teeth are replaced with standard dental implants. How long zygomatic implants last, and what affects that, is covered in more depth in how long do zygomatic implants last.

Who Are Zygomatic Implants For?

They are considered for people whose upper jaw bone has resorbed too far for standard implants. The usual causes are many years without teeth, advanced gum disease and long use of a removable denture. Bone loss after tumour surgery or trauma to the upper jaw is another group. A systematic review of 10 studies found that the main indication was extreme upper jaw bone loss, while noting that the studies did not share one definition of extreme bone loss and that clearer indications need further research (PubMed 37391575).

When they are not the first choice matters just as much. If the bone is enough for standard implants, or can be made enough with bone grafting and a sinus lift, zygomatic implants are usually not the first option, because those routes reach the same goal with less extensive surgery. Untreated sinus infection is dealt with first. If general health will not allow a long operation, the plan changes.

Diabetes control, regular medication and smoking are discussed at the examination. Smoking is a measured risk factor for implant failure: across 292 publications, implants in smokers had an odds ratio for failure of 2.402 (PubMed 35056347). Your expectations, how many operations you are willing to have and how long you are prepared to wait are part of the decision too. Suitability is only clear once the CBCT scan has been read.

How Are Zygomatic Implants Placed?

Planning rests on a 3D CBCT scan. The scan shows how much bone is left in the upper jaw, whether the cheekbone is thick enough to hold the implant, the state of the sinuses and the floor of the eye socket. From these measurements the path of each zygomatic implant and the number needed are set. At Mosdent the number of implants, the bridge type and whether an interim bridge can be fitted early are written into the plan after the examination.

The path the implant takes to the cheekbone depends on the technique: the classic route through the sinus, a technique that opens a slot in the sinus wall, and a route outside the sinus. A meta-analysis of 35 studies found survival highest with the classic and extra-sinus techniques and lowest with the sinus slot technique, and the authors stressed that case and technique selection is key to reducing complications (PubMed 37847828). The shape of the bone and the sinus wall decides which technique is used.

Because the work is close to the sinus and the eye socket, the operation takes longer than standard implant surgery and is carried out under sedation or general anaesthesia. Once the zygomatic implants are in, standard implants are added at the front if the plan calls for them. How firmly the implants hold is measured during surgery, and that measurement decides when the interim fixed bridge can go in.

Treatment Process

1. 01Examination and CBCT: Remaining bone, the sinuses, the cheekbone and general health are assessed on a 3D scan; the path and number of zygomatic implants are planned.
2. 02Surgery: Zygomatic implants are placed under sedation or general anaesthesia; standard implants are added at the front if the plan calls for them.
3. 03Interim Fixed Bridge: If the implants are firmly stable at placement, an interim fixed bridge is screwed on shortly afterwards; if not, they heal without load.
4. 04Final Bridge: Once bone and soft tissue healing has been checked, records are taken and the final bridge is screwed onto the implants.
5. 05Check-ups: The sinuses, the gum around the implants and the bridge screws are checked regularly; a blocked nose or facial pain should be reported early.

How Long Does Treatment Take?

The timeline depends on your bone and on how soon after surgery the interim bridge can be fitted, so it is listed as case-dependent. The clearest difference from a graft-based plan is that the months of waiting for a graft to heal fall away. In the randomised trial assessed by a Cochrane review, time to fixed teeth averaged 1.3 days with zygomatic implants and 444 days with standard implants placed in grafted bone (PubMed 42489150).

Treatment is completed in two stages. The first covers the scan, surgery and an interim fixed bridge. The interim bridge restores appearance and speech, but it is not designed for heavy biting. In the second stage, once bone and soft tissue healing has been checked, new records are taken for the final bridge, which is then screwed onto the implants.

Immediate loading, meaning an interim bridge fitted shortly after surgery, is well studied with zygomatic implants. In a review of 68 studies, the 26 studies that used only immediate loading had a significantly lower failure rate than the 34 studies using delayed loading (PubMed 27422530). If the implants are not stable enough, they heal without load and the timeline lengthens.

For visitors from abroad, the dates for both stages are set at the first examination, and the follow-up schedule is written into the plan.

How Long Do Zygomatic Implants Last?

Long-term data on zygomatic implants come from a wide body of studies. A review by Chrcanovic and colleagues pooling 68 studies, 2,161 patients and 4,556 zygomatic implants recorded 103 failures and a 12-year cumulative survival of 95.21%, with most failures detected within the first 6 months after surgery (PubMed 27422530). In other words, once an implant has come through the healing period, the chance of losing it later falls.

A more recent meta-analysis included only studies with at least 3 years of follow-up. Across 18 studies, the 1,349 zygomatic implants placed in 623 patients had mean survival of 96.2% at 6 years, and bridge survival was 94% (PubMed 37405545). The authors judged long-term survival comparable to standard implants and found significantly higher survival with immediate loading than with delayed loading.

Direct comparisons exist too. In 18 studies with at least 5 years of follow-up, covering 2,972 zygomatic and 2,462 standard implants in 1,709 patients, mean survival was 96.5% and 95.8%, with no significant difference between the groups (PubMed 36373779). These are averages; smoking, oral hygiene and regular check-ups shape an individual result.

Patients' own assessments have been measured as well. A systematic review of patient-reported outcomes found clear gains in quality of life, especially in chewing and appearance, and zygomatic implant survival of 98.3% after a mean follow-up of 46.5 months (PubMed 35044889).

Options: Classic, Quad and Graft-Based Plans

Zygomatic implants are used in different layouts. In the classic layout, one zygomatic implant is placed on each side and joined to standard implants at the front in one bridge. If the front of the jaw also lacks bone, two zygomatic implants go on each side, a plan known as quad zygoma. If bone loss affects one side only, a single zygomatic implant is joined to standard implants on that side. In the review of indications, the quad layout was used in 107 patients, the classic layout in 88 and the one-sided layout in 14 (PubMed 37391575).

Results for the quad layout have been pooled separately. A meta-analysis of 11 studies and 166 patients found implant survival of 98%, and the most frequent complications were sinusitis in 12% and implant malposition in 11% (PubMed 33600519). The authors conclude that survival is high but that the rate of complications should not be underestimated.

The alternative to zygomatic implants is a graft-based plan. The upper jaw bone is built up with graft material and a sinus lift, the graft is left to heal, and standard implants are placed afterwards. This route takes longer but involves less extensive surgery. In some cases pterygoid implants, which anchor in bone at the back of the upper jaw near the base of the skull rather than in the cheekbone, are another option; the choice depends on where the remaining bone is.

Risks and Limitations

Sinusitis is the most common complication of zygomatic implants. In the review of 68 studies, sinusitis occurred in 2.4%, soft tissue infection in 2.0%, numbness in 1.0% and an opening between mouth and sinus in 0.4%; the authors noted that many studies did not report these complications, so the figures may be underestimated, and that sinusitis can appear several years after surgery (PubMed 27422530). A long-term meta-analysis found sinusitis prevalence of 14.2% at 5 years (PubMed 37405545).

Sinusitis varies clearly with technique. A meta-analysis comparing 18 sinus lift studies with 9 zygomatic implant studies found sinusitis in 1.11% after a sinus lift and 3.76% after zygomatic implants; among zygomatic techniques it was 0.00% with the extra-sinus route, 4.36% with the intra-sinus route and 21.62% with the sinus slot technique (PubMed 37266797). Technique is therefore chosen with the sinuses in mind, not only the bone.

Complications around the eye are rare but serious. A systematic review on this topic found infraorbital numbness to be the most common problem, followed by entry into the eye socket during surgery; of 41 cases with reported outcomes, 10 needed further procedures and 5 had irreversible damage (PubMed 39310386). These risks are why detailed CBCT planning and an experienced surgical team are essential.

Zygomatic implants are used only in the upper jaw. No implant treatment promises a lifelong result: the bridge can break, screws can loosen and inflammation can develop around an implant. Treatment is therefore planned together with follow-up appointments.

Aftercare

Swelling and bruising of the face are expected in the first days after surgery; avoid blowing your nose hard and take the prescribed medication as directed. Soft foods are best while the interim bridge is in place. A blocked or runny nose, cheek pain or a bad smell can be signs of sinusitis and should be reported without waiting; because sinusitis can appear years after surgery, this advice still applies after the final bridge is fitted.

Daily care means cleaning the underside of the bridge and the points where the implants come through the gum. A water flosser, interdental brushes or thick floss can be used, and which one fits under your bridge is chosen together once the final bridge is in. The point where a zygomatic implant comes through can sit close to the palate, so this area is shown to you separately. At check-ups the bridge is removed when needed and the gum around the implants and the screws are examined.

Smoking harms healing and the long-term result, so stopping is discussed as part of treatment. If you grind your teeth at night, a night guard may be advised to reduce the load on the bridge. How often you are seen is written into your plan, and for visitors from abroad the way follow-up is arranged is agreed at the first examination.