Subperiosteal Implants: When Nothing Else Works

When the jawbone has resorbed to the point where standard implants no longer have enough bony support, that does not necessarily mean fixed teeth are impossible. In cases of pronounced atrophy of the upper jaw we use advanced implantology techniques such as transnasal, zygomatic, trans-sinus and pterygoid implants, depending on the patient’s individual 3D anatomy and on the plan for the future fixed restoration. In a severely atrophic lower jaw, one of the options, where the indication for it is correct, is customised subperiosteal implants.

In our niche, patients like these are frequent visitors: people who have been told in more than one place that fixed teeth are not possible. This text explains two rarely available techniques, subperiosteal and transnasal implants, when they come into consideration and what the peer reviewed literature says about them today, honestly, with the figures and with the limitations.

The subperiosteal implant: a framework on the bone, not in it

A conventional implant is a screw that goes into the jawbone. A subperiosteal implant works differently. It is a custom made titanium framework that rests on the surface of the remaining bone, beneath the mucosa, with posts emerging from it to which the fixed bridge is attached. The idea is not new, the first versions go back to the middle of the last century, but the frameworks were then made by hand, from an impression of the bone, and the results were inconsistent.

What brought the technique back into serious discussion is digital manufacturing. Today the framework is designed on a computer from the patient’s CBCT scan and produced by additive manufacturing (metal 3D printing), so that it follows the individual anatomy of the remaining bone precisely. That is why modern customised subperiosteal implants can be considered in pronounced atrophy, when the remaining bone does not provide suitable conditions for conventional implant anchorage.

The current data is encouraging, but calls for caution. A 2024 systematic review (Anitua et al.), which covered 227 patients, reported survival of 97.8 per cent over a mean follow-up of 21.4 months. At the same time it also recorded the sensitive point of the technique: in roughly a quarter of the implants (25.6 per cent) there was partial exposure of the framework through the gum, and a smaller proportion of patients had a soft tissue infection. Survival is therefore high, but soft tissue complications are not rare, and there is still not enough long term data.

The transnasal implant: support at the floor of the nose

In pronounced atrophy in the anterior part of the upper jaw, the bone that the front of the bridge would anchor into disappears. This is where the transnasal implant comes in. It uses the denser bone along the floor of the nasal cavity and along the lateral walls, in the region of the inferior nasal concha, where the bone can remain firm even when the alveolar ridge is severely resorbed. Part of the implant passes through that bony bridge between the sinus and the nasal cavity.

In practice, transnasal implants are rarely placed on their own. Most often they complement zygomatic implants, providing additional firm support in the anterior part of the upper jaw. This can reduce or avoid the anterior cantilever, the part of the bridge that has no direct support and is biomechanically less favourable. The description of the Z-Point technique (Oh et al., 2023) cites precisely this as one of the main reasons for using them in severely resorbed jaws.

A series of 10 patients published in 2025 (Eshoiee et al.) reported 18 transnasal implants with 100 per cent clinical success after one year and marginal bone loss of about 0.70 mm, which is comparable to conventional implants. This is a small sample with short follow-up, so the results read as a promising start rather than definitive proof. Even so, in carefully selected patients they show that support at the nasal floor can be stable.

When these techniques come into consideration at all

What these techniques have in common is that they are not the starting point when there is enough bone for standard implants. Our order of reasoning usually goes like this:

• if there is enough bone, a conventional implant or a standard All-on-4,
• if there is not enough bone in the upper jaw for standard implants, then depending on where the remaining bone is, transnasal, zygomatic, trans-sinus or pterygoid implants come into consideration,
• in pronounced atrophy of the lower jaw, where the indication for it is correct, customised subperiosteal implants come into consideration, as do short or ultra-short implants and, in selected cases, lateralisation or transposition of the inferior alveolar nerve (IAN).

A subperiosteal implant is considered when the ridge is severely atrophic and there is not enough bone for standard implant anchorage, while a transnasal implant uses firm bony support alongside the nasal cavity in pronounced atrophy of the premaxilla, that is, the anterior part of the upper jaw. The decision is not made by the patient’s wish or by a list of techniques, but by the 3D analysis of the bone, the position of the sinus, the nerves and the nasal cavity, and general health.

What the path with us looks like

The first step is always an examination and complete digital X-ray diagnostics, including a 2D panoramic image and a 3D CBCT scan, which at our clinic are part of the free first examination. On the basis of the 3D data the procedure is planned digitally, before anyone enters the operating theatre. For patients for whom travelling is difficult, a preliminary assessment based on a scan sent to us is also possible.

We perform procedures as demanding as these under potentiated intravenous analgosedation, the depth of which is adapted to the patient and to the procedure, from lighter sedation, during which the patient cooperates and follows instructions but feels no fear or tension and usually remembers little or nothing of the procedure, to deep sedation, during which the patient essentially sleeps through the procedure.

We support recovery medically, as part of the DENTAL SPA concept: before the procedure we carry out lymphatic drainage, during the procedure ozone therapy and intravenous supplementation with vitamins, minerals and amino acids, and after the procedure torsion field magnetotherapy and, according to indication, hyperbaric oxygen therapy (HBOT). With procedures as demanding as these, DENTAL SPA treatments are not an addition to the main therapy but an integrated part of our perioperative protocol, aimed at creating the most favourable possible conditions for healing, a better postoperative recovery and support for the biological processes that matter for osseointegration. Precisely with techniques where soft tissue healing can be one of the more sensitive points of treatment, this approach to recovery is for us an integral part of the overall treatment planning.

An honest frame for expectations. Subperiosteal and transnasal implants are advanced and technically demanding implantology techniques intended for clearly indicated cases. When they are correctly indicated, precisely planned and expertly performed, they are serious implantology solutions for patients in whom standard techniques are no longer sufficient because of a pronounced lack of bone. Published studies record high survival rates, alongside the fact that long term follow-up for these rarer techniques is still more limited than for conventional implants. That is exactly why the key to success is not choosing the “most advanced” technique, but the correct indication and its precise execution. The method has to be adapted to the patient, not the patient to the method.

Who they are not the right option for

An honest assessment also means saying when something is not for you. These techniques require additional preparation, or are not the first choice, in cases of active inflammation of the sinus or the nasal mucosa, with some general health conditions and medications (for example certain bone medications or recent oncological treatment), with active smoking and poor oral hygiene, and with unrealistic expectations about healing and aftercare. In such cases we suggest preparation, postponement or another route. The number of patients for whom fixed teeth really are not possible is small, but whether advanced implantology techniques can be used always depends on the correct indication, the anatomy and the health status of the particular patient.

The next step. If you have been told that a pronounced lack of bone leaves you no possibility of fixed teeth, a second opinion with a 3D analysis makes sense even when you have already heard “no”. At the free first examination we assess the state of the bone honestly and tell you whether one of the advanced implantology techniques is correctly indicated in your particular case.

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