Who is All-on-4 suitable for — and who is better served by something else?

All-on-4 suits someone whose whole jaw is lost or beyond saving, who has enough bone in the front section for four implants (Implantate) to anchor in, whose general health allows a surgical procedure and normal healing, and who is willing to clean a fixed bridge every day for the rest of their life. Age is rarely the deciding factor — people in their seventies and eighties are treated routinely, while a thirty-year-old with a healthy jaw is usually the wrong candidate for entirely different reasons. What genuinely narrows the field is uncontrolled general illness, heavy smoking, untreated gum disease, certain bone medications, and expectations that no dental work can meet. Everything on that list is a conversation, not an automatic refusal — but it has to be an honest conversation, held before the plan is drawn up rather than after.

Most descriptions of this treatment are written for the people it fits. They are accurate and they are incomplete, because a treatment concept is only genuinely useful when you also know who it does not fit.

So this article is organised around the harder half. Below you will find three groups — a clear fit, a “depends on the assessment”, and a “usually better served by something else” — followed by the health factors that move people between the groups. None of it replaces an examination, and the honest limit of any article is that it cannot see your jaw. What it can do is tell you which questions your consultation should answer.

You already wear a full upper or lower denture and are unhappy with it. This is the largest group by some distance. A lower denture (Prothese) in particular has very little to hold onto and tends to lift when you laugh, talk or eat. Moving to teeth fixed on implants removes that daily management. In the upper jaw, a fixed bridge also leaves the palate uncovered, which is why people so often mention that food started tasting like food again.

Your remaining teeth in one jaw have a poor outlook. Several loose teeth from advanced gum disease (Parodontitis), a bridge that has failed, roots that will not support anything further — the point at which patching stops being the sensible answer.

You have lost bone at the back of the jaw. This is the situation the concept was designed around. Because the rear implants are placed at an angle and anchor in the front section, where bone is usually better preserved, full-arch treatment is often possible where a full set of straight implants would first require rebuilding the jaw.

You want fixed teeth rather than something you take out. Not everyone does. But for people who find a removable denture unacceptable — for reasons of function, of taste, or simply of dignity — this is the point of the whole exercise.

You have diabetes, a heart condition, or another chronic illness. Well-managed, these are usually compatible with implant treatment. Poorly controlled, they change the calculation. More on this below.

You smoke. Not an automatic no, but a real risk factor that has to be discussed openly.

You have osteoporosis or take medication that affects bone. This one requires proper assessment and often contact with your treating doctor.

You still have a number of teeth that could technically be kept. Then the question is not really “is All-on-4 for me” but “which concept fits my jaw” — a different comparison, covered in its own article.

Your bone is very reduced even in the front section. Sometimes additional implants, bone grafting (Knochenaufbau) or a different design is the answer. Only a 3D X-ray (DVT) can settle this.

Most of your teeth are healthy. If you have one gap, or two, you need an implant or a bridge for that gap — not a full-arch discussion. Healthy teeth with a good long-term outlook are not removed to make room for a concept, and any recommendation to extract should come with a stated reason for that specific tooth.

You have untreated, active gum disease. Not a permanent exclusion — a sequence. Inflamed tissue is the wrong foundation for implants, so periodontal treatment comes first and the implant plan follows. This adds weeks to the front of the timetable and is not a step worth skipping.

You are not able or willing to maintain it. A full-arch bridge has to be cleaned under as well as around, daily, with interdental brushes and usually a water flosser, plus regular check-ups and professional cleaning (professionelle Zahnreinigung, PZR). Where dexterity is severely limited or there is nobody to help, that is a genuine planning problem and deserves an honest look at removable alternatives, which can be cleaned in the hand.

You are expecting the treatment to solve something it cannot. More on this below, because it is the criterion most often skipped.

This is the part of the assessment that decides most borderline cases.

Diabetes. Implants and diabetes are compatible when blood sugar is well controlled. What matters is the level of control over time rather than the diagnosis itself, because raised blood sugar affects wound healing and the body’s response to infection. Bring your current values to the consultation. Diabetes also interacts with gum disease in both directions, which makes cleaning and check-ups after the treatment particularly important.

Smoking. Smoking reduces blood flow in the gum tissue and is consistently associated with a higher rate of implant complications; German dental associations treat it as one of the significant modifiable risk factors in implantology. It does not automatically rule the treatment out, and no one is going to lecture you. But your dentist needs an honest number rather than a polite one, and many patients use the surgery date as a reason to stop or substantially cut down, at least around the healing period.

Osteoporosis and bone medication. Osteoporosis itself is not an exclusion. What requires careful assessment is medication from the antiresorptive group — some osteoporosis and cancer treatments, given as tablets or infusions — because of their effect on bone healing after surgery in the jaw. This is exactly the situation in which your dentist should be in contact with the doctor prescribing it. Bring the name and dose of everything you take, including anything given by injection or infusion, even if you stopped it some time ago.

Blood thinners. Very common, and generally manageable. They need to be known about in advance so that the surgery can be planned appropriately. Never stop or adjust such medication on your own initiative before a dental appointment — that decision belongs to the doctor who prescribed it.

Radiotherapy to the head or neck, and immunosuppression. Both affect healing in the jaw and require individual assessment, usually in coordination with the treating specialists. Neither is automatically an exclusion, and neither is something to leave unmentioned.

Older patients. There is no upper age limit as such. What is assessed is general health, healing capacity and the ability to manage the aftercare — an active 78-year-old is frequently a better candidate than an unwell 55-year-old. For many older patients the argument is quality of life in the years they have now: being able to eat in company, to speak without adjusting a plate, to stop thinking about their mouth.

Younger patients. Here the caution runs the other way, and for a reason that surprises people. Someone in their thirties facing full-arch treatment usually has an underlying cause — severe gum disease, a systemic condition, an accident — and that cause needs addressing on its own terms. A young jaw also has to carry the result for a very long time, so preserving natural teeth wherever they can be preserved carries even more weight than usual.

Growth. Implants are not placed in a jaw that is still growing, which is why this treatment does not apply to adolescents.

A fixed full-arch bridge is not a repair you can forget about. It is a structure you maintain — and the maintenance is a fair criterion for suitability, not an afterthought.

Manual dexterity. Cleaning under a bridge with interdental brushes needs reasonably steady hands. Where arthritis or a neurological condition makes that difficult, say so at the planning stage. Sometimes the answer is an adapted routine or help at home; sometimes it is a different design.

Regular attendance. Check-ups and professional cleaning are the mechanism by which problems get caught early. The tissue around implants can become inflamed (peri-implantitis) when plaque is left undisturbed, and that is the most common reason implants get into difficulty years after a perfectly successful surgery.

Realism about the routine. The most useful question you can ask at the consultation is not about the surgery. It is: show me exactly what I will have to do every evening. If you look at that and think “no”, that is valuable information — arrived at before treatment rather than after.

Implants replace teeth. They do a great deal, and there are things they do not do.

The comparison that matters. The honest benchmark is not “the healthy mouth I once had” but “my mouth as it is now”. Patients who hold that comparison in mind are, as a rule, the ones who describe the outcome most positively afterwards. Studies report implant survival of around 95 % and above, but no responsible dentist promises an individual outcome, and you should be wary of anyone who does.

A substantial share of people who need full-arch work have been avoiding dentists for years. That avoidance is often the reason the jaw reached this state, and it deserves to be treated as part of the case rather than a character flaw.

Dental anxiety does not disqualify you. Treatment can be carried out under sedation or with laughing gas (Lachgas), which does not remove sensation but does remove the vigilance, and which for many anxious patients is the difference between a treatment they can face and one they cannot. Say it at the first appointment — before the examination, not after. It changes how the whole plan is built, including how appointments are scheduled and how much is explained in advance.

An out-of-hours dental service (Notdienst) covers evenings and weekends across Germany. Our own hours are Monday to Friday 07:30–19:30 and Saturday 08:00–18:00.

Two practical points specific to your situation, both of which affect suitability rather than just convenience.

Your medical history has to survive translation. Medication names differ between countries, and a drug you take under one brand name may be listed differently here. Bring the packaging or a printed list, and if you have had head or neck radiotherapy, bone infusions or major surgery abroad, bring the documentation. This is the one part of the assessment where a language gap can genuinely change a clinical decision.

Your timetable matters. Full-arch treatment involves a surgical day and a healing phase of three to six months before the definitive bridge, plus the formality that a treatment and cost plan (Heil- und Kostenplan, HKP) must go to your statutory health insurance fund (gesetzliche Krankenversicherung, GKV) before treatment begins, with processing times vary from fund to fund. If you are on a contract ending in five months, say so at the first appointment so the plan can be built around it.

For treatment of this scale, patients travel further than they would for a check-up — to Wuppertal from across NRW, with Düsseldorf, Cologne and Bonn all within a short drive, and from further afield in Germany, because being able to discuss your medical history in your own language is worth more than the nearest practice. If that is your position, start with English-Speaking Dentist in NRW, and the treatment itself is described on Dental implants – service page (EN).