Are you a good candidate for Invisalign? An honest suitability check

Clear aligners (Aligner) suit a large share of adults who want their teeth straightened, but suitability is decided by three separate things, not one: whether your mouth is healthy enough to start, whether your particular misalignment falls within what aligners can move, and whether your daily routine will really tolerate wearing them around 22 hours a day. Most people fail on the third point rather than the first two. Untreated decay, active gum disease and unfinished dental work have to be dealt with before treatment begins, whatever your case looks like. In Germany, adults pay for aligner treatment privately as a rule; at our practice in Wuppertal, clear aligner treatment costs 1,049 €, 2,800 € or 3,699 € depending on the scope of the case, and the assessment that tells you whether you are a candidate is free.

Patients usually arrive with the middle question — can aligners fix my teeth? — and are surprised that we start somewhere else. The order matters, because a case that fits the tool perfectly still cannot start if the foundation underneath it is unsound, and the most technically straightforward plan in the world fails if the trays spend their days in a pocket.

So: is your mouth ready, does your case fit, and does your life fit. Take them one at a time.

Aligners move teeth through living bone and against living gum. Anything that compromises either has to be settled first — not as bureaucratic caution, but because moving teeth in an inflamed mouth makes the inflammation worse.

Untreated decay (Karies). A cavity has to be filled before treatment planning, and here is the practical reason: a filling changes the shape of the tooth, and the trays are manufactured to the shape the tooth had on scanning day. Fill first, scan second.

Gum disease (Parodontitis) and gingivitis. Bleeding, swollen gums must be treated and stabilised before any tooth is moved. Where the supporting bone has already been lost, orthodontics is not automatically ruled out — but it becomes a more careful, more closely monitored treatment, planned with the gum condition in view. German dental associations are consistent on this point: periodontal health comes before tooth movement.

Old crowns, veneers and large fillings. They do not disqualify you, but they change the plan. See the dedicated section below.

Loose or failing dental work. A crown that needs replacing is better replaced before, not during, a course of aligners.

Wisdom teeth (Weisheitszähne). Sometimes they need to come out first, sometimes they are irrelevant, and sometimes the decision is deferred. This is judged individually rather than by rule.

Your own routine at home. If plaque control is currently patchy, trays that sit against the teeth for 22 hours a day will not improve matters. A professional cleaning (professionelle Zahnreinigung, PZR) before starting, and a realistic home routine, are part of the preparation rather than an upsell.

Aligners handle the everyday range of adult orthodontics well: mild to moderate crowding, gaps and spacing, front teeth that have drifted over the years, relapse after braces worn as a teenager, and many bite corrections when combined with attachments and elastics.

They get harder as the case gets more three-dimensional — teeth that must be rotated substantially, teeth that need to be moved up or down within the bone, roots that need genuine tipping rather than crown movement. And they reach a hard boundary where the problem is not the teeth at all but the size and position of the jaws, because no removable appliance changes the length of a jawbone.

That capability envelope is a subject in its own right, and it is set out movement by movement in Can clear aligners move every tooth? Possibilities and limits (EN). For the purpose of deciding whether to book an assessment, one sentence covers it: if your concern is how your teeth are arranged, aligners are usually in the running; if your concern is the shape of your jaw or your profile, they may not be.

This is where suitability is actually won or lost, and it is worth being blunt with yourself before someone else has to be.

The 22-hour rule is not padding. The trays only apply force while they are on the teeth. Two hours out is enough for meals and cleaning. Four or five hours out — a long lunch, a dinner, an evening of drinks — is a plan quietly slipping behind schedule.

Grazers struggle. If you eat something small every hour or drink anything other than water throughout the day, aligners will fight your habits every single day. Trays must come out for everything except water, and teeth should be cleaned before they go back in. People who eat three defined meals adapt within a week. Constant snackers usually have to change how they eat, which is a real cost worth acknowledging in advance.

Coffee and tea all day is the classic collision. Hot drinks with trays in can warp the plastic and stain it. This is the single most common complaint from office workers, and the honest answer is that the pattern has to change.

Jobs with constant speaking. Teachers, lawyers, sales people and anyone who presents daily: you will lisp slightly in the first days, and it usually settles within one to two weeks. Aligners are far less visible than brackets, which is why many people in client-facing roles choose them in the first place — but the first fortnight is real.

Travel and shift work. Frequent travellers do well provided they carry the current and next tray, plus a case and a travel brush. Aligners are arguably easier than brackets here, because there is no wire to break in a city where you know no dentist.

Forgetfulness is a diagnosis of sorts. If you already lose sunglasses, keys and headphones regularly, factor that in. Trays wrapped in a napkin at a restaurant end up in the bin — this happens weekly, everywhere, to intelligent adults.

Smoking. Smoking with trays in discolours them, and smoking generally works against gum health during treatment. It is not a formal exclusion, but it is a genuine disadvantage.

Read these eight statements and count how many you can answer with a straightforward yes:

1. My gums do not bleed regularly when I brush. 2. I have no untreated decay that I know of, and I have seen a dentist within the past year. 3. I eat at defined times rather than nibbling continuously. 4. I could realistically restrict hot drinks to defined breaks. 5. I can build a new two-minute habit and keep it for a year. 6. My main concern is the position of my teeth, not the shape of my jaw or chin. 7. I am willing to wear a retainer afterwards — at night, indefinitely. 8. I would rather have a plan in writing than a quick promise.

Six or more, and you are very probably a candidate on the behavioural side. Three or fewer, and the honest conversation is whether fixed braces — which work whether or not you cooperate on a given day — would serve you better. Wanting aligners is not the same as suiting them, and there is no shame in the second answer.

Existing dental work is one of the most common reasons adults assume they are not candidates. Usually they are — with caveats worth knowing.

Crowns (Kronen). Teeth with crowns can be moved. The attachments that grip the tooth bond less reliably to ceramic than to natural enamel, so the plan works around them. Note also that a crown made to fit your old tooth position may look subtly wrong in the new one, and occasionally needs replacing at the end — better budgeted for at the start than discovered at the finish.

Veneers. Same principle, with more aesthetic sensitivity. If you are considering veneers and straightening, the sequence is nearly always: straighten first, then restore. Restoring first and moving afterwards wastes the restorations.

Implants (Implantate). An implant is fused to bone and does not move — ever. Aligners move the teeth around it. One or two implants rarely prevent treatment; several in strategic positions can genuinely limit what is achievable, because the plan loses its anchors and its freedom.

Bridges (Brücken). A bridge splints several teeth into one rigid unit, and those teeth cannot then be moved independently. Depending on where the bridge sits, this ranges from irrelevant to decisive.

Missing teeth. Gaps can be closed orthodontically or preserved deliberately to receive an implant or bridge later. That is a planning decision to make at the beginning, together, because reversing it costs months.

Teenagers. Aligners for adolescents are established, and modern trays include indicators that show whether they have really been worn. Suitability here is as much about the teenager as the teeth: a fourteen-year-old who is organised and motivated does well; one who forgets a PE kit twice a week is better served by an appliance that cannot be removed. Note the German-system point — where a statutory fund covers a young patient’s treatment, aligners are usually a private add-on rather than the standard option.

Adults 20 to 50. The core group, and the one for whom aligners were effectively designed. Bone remodels perfectly well; the practical limits are usually gum health and existing dental work.

Adults over 60. Age alone excludes no one. What matters is how much bone supports the teeth and how stable the gums are. Where support has been lost, forces are kept lighter, movements more modest, and goals more targeted — often improving function and cleanability rather than pursuing a textbook alignment. Many people at this stage are treating a specific problem, and that is a perfectly good reason to treat.

Bring your medication list to the consultation. Some medicines affect bone turnover or gum tissue, and both matter when teeth are being moved. Uncontrolled diabetes raises the risk of gum problems during treatment; well-controlled diabetes is a much smaller consideration. If you are pregnant or planning to be, say so — gums react more strongly to plaque in pregnancy, and the timing of scans and X-rays is planned accordingly. Persistent teeth grinding (Bruxismus) does not rule out aligners, but it shapes the retention plan afterwards.

None of these is a reason to stay away. All of them are reasons to mention things that feel unrelated to your teeth.

The suitability assessment at our practice is a first consultation, and it is free. In practice it means: an examination of the teeth, gums and bite; a digital scan with Primescan, which takes minutes and needs no impression trays; photographs; and X-ray imaging where the roots or unerupted teeth need to be seen. Scans are reviewed with AI support alongside the dentist’s own assessment — the assessment stays with the dentist.

You should leave with three things: a clear statement of what can and cannot be achieved with aligners in your case, an alternative if aligners are not the right tool, and the cost in writing. A digital simulation of the planned result is a planning tool, not a photograph of the future — worth seeing, worth not over-reading. What such images can and cannot tell you is discussed in Invisalign before and after: what the photos show — and what they don’t (EN).

For adults, orthodontics is as a rule not covered by statutory health insurance (gesetzliche Krankenversicherung, GKV) in Germany — so for most adult patients the question is not what the fund pays but what the treatment costs and how it is paid. Our clear aligner treatment is offered at 1,049 €, 2,800 € or 3,699 €, the differences reflecting how much movement the case requires, and instalment payment (Ratenzahlung, subject to a credit decision) is available.

For children and adolescents the mechanism is different: statutory funds grade cases with KIG (Kieferorthopädische Indikationsgruppen) on a scale of 1 to 5 and cover treatment only from grade 3 upwards, with treatment starting before the eighteenth birthday. Grades 1 and 2 count as aesthetic and are paid privately. Aligners for a covered young patient are typically an extra-cost option alongside the standard appliance. The full process is set out in Will my health insurance pay for a brace? (EN).

Private health insurance (private Krankenversicherung, PKV) and supplementary dental cover (Zahnzusatzversicherung) reimburse a share set by the tariff depending on tariff — but nearly always require the plan to be submitted before treatment starts, and most have a waiting period after the policy begins.

Suitability conversations are full of conditionals — if the roots allow, if the gum stabilises, if the wear time holds. Those nuances are exactly what gets lost in a second language, and they are exactly what determines whether you are happy at the end.

We treat patients in English; our team’s working languages also include German, Russian, Turkish, Ukrainian, Arabic, Kurdish and French. That means you get the finding, the alternatives, the limits and the price explained in English, and in writing before anything begins. If you have recently moved here, English-Speaking Dentist in NRW explains the system essentials — the treatment plan, the insurance card, what gets approved before it is done.

Adults routinely travel for aligner treatment, and Wuppertal is well placed for it: Düsseldorf, Cologne and Bonn are within comfortable reach, and patients come to us from across NRW and from further afield in Germany. For a treatment measured in months, thirty minutes to a practice that will explain the limits honestly in your language is not a detour.