Wanting straighter teeth without metal brackets is the easy part. Whether you’re a good candidate for Invisalign® comes down to how far your teeth have to move. Mild to moderate crowding, spacing, and rotation usually qualify. Bigger bite problems often need fixed braces instead.
What can Invisalign correct?
Clear aligners handle cases where teeth need to shift rather than be rebuilt around. The American Association of Orthodontists lists what aligner treatment addresses. Gapped teeth, crowding, overbite, underbite, open bite, crossbite, and crooked teeth are all on that list. Mild to moderate versions of each respond best.
What those look like in an actual mouth:
- Crowding, where teeth overlap because the arch is narrower than the teeth need. Mild and moderate crowding moves well.
- Spacing, meaning gaps between teeth that drifted apart or never met. Several small gaps close more predictably than one big one.
- Mild rotation, where a tooth is turned in its socket rather than out of line with the arch.
- Relapse after earlier braces, which is common in people who stopped wearing a retainer and watched the front teeth drift back.
- Bite issues at the milder end, including a deep bite, a small open bite, or a crossbite on one or two teeth.
The pattern behind that list is worth noticing. Aligners are good at tipping teeth and sliding them short distances.
That’s the line your dentist is really checking. How the aligners produce any movement at all explains why the line falls there, and it’s worth reading before you commit to wearing them.
Mild to moderate is doing a lot of work in that list, and it isn’t a judgment about how your teeth look to you. It describes how far each tooth has to travel, which gets measured in millimeters on a scan rather than assessed in a mirror.
That’s why two people with similar-looking crowding can get different answers. The one with a tooth that needs moving twice as far is a different case, even though the smiles look alike.
What can Invisalign not correct?
Some movements are hard for a removable appliance to produce. Severe crowding, large gaps, and teeth rotated past a certain point are the usual reasons a dentist says no. So are bite problems that need the jaw relationship changed. The American Association of Orthodontists notes that some cases are treated more predictably with braces.
Severe crowding is the most common one. Where there’s no room for teeth to move into, something has to give. Either the arch gets widened, or teeth come out to make space, and neither is a small addition to the plan.
Large gaps are the mirror image. Moving a tooth a long way bodily is different work from tipping it. Fixed brackets do it more reliably, because a bracket grips the tooth while an aligner presses on it.
Severe rotation runs into the same limit. A round tooth like a premolar gives a smooth plastic shell very little to push against. Past a certain angle the aligner slips rather than turns it.
Then there are the bite problems that aren’t really about the teeth. A significant overbite or underbite is often a difference in how the jaws sit relative to each other. Moving the teeth can disguise that. It doesn’t change the relationship underneath, which sometimes needs surgery in an adult.
Being told braces are the better answer is a normal outcome, not a rejection. The American Dental Association treats fixed braces and removable aligners as two routes to the same result. Which one you get is chosen by what the case needs. A referral to an orthodontist for a complex case is the same logic.
Will you actually wear them?
Wear time is the candidacy factor nobody lists, and it’s the one you can answer yourself. The American Association of Orthodontists puts the requirement at least 22 hours a day. Each aligner is worn about a week. That leaves roughly two hours for meals, for drinks other than water, and for brushing.
Aligners only move teeth while they’re in.
Two hours is less than it sounds. Three meals, a coffee, and brushing twice uses most of it. Every one of those means taking the aligners out, putting them somewhere, and putting them back.
Time out of the mouth isn’t neutral either, because teeth drift back toward where they started. That’s also the main reason one course runs longer than another.
Some working lives make this genuinely hard. If you talk for a living, the first days in a new aligner can affect your speech. If you graze through the day rather than eating at set times, the aligners spend those hours in a case.
Say that at the assessment rather than finding out three months in. Wear time rules people out for practical reasons rather than clinical ones, and there’s nothing wrong with landing there.
Fixed braces work while you sleep, while you eat, and while you forget about them. For some people that reliability is the deciding advantage.
Does age or existing dental work affect candidacy?
Age doesn’t, on its own. Adults at any age can be candidates as long as the gums and the bone holding the teeth are healthy. Existing dental work matters more. Crowns and bridges change how the aligner grips, and an implant won’t move at all, because it’s fused to the bone.
The implant point catches people out. A natural tooth sits in a socket and shifts when steady pressure is applied. An implant is joined to the bone and stays exactly where it was placed, so a plan involving one has to move everything else around it.
Crowns and veneers move fine, since the root underneath is what’s moving. What they affect is the small tooth-colored attachments bonded to teeth during treatment. Those bond differently to porcelain than to enamel.
A bridge is the harder case. It splints two or more teeth into a single unit, and a unit can’t be moved tooth by tooth.
Gum health comes before all of it. Teeth can’t be moved safely through inflamed or infected tissue, so gum disease gets treated first and the aligners wait. That’s a sequencing issue rather than a no.
What happens at the assessment?
Photographs, an intraoral scan, and a digital treatment plan. The scan builds a 3D model of your teeth, and the plan shows the movement step by step before a single aligner is ordered. That’s what turns candidacy from an opinion into something you can look at.
The scan takes a few minutes. A small wand passes over the teeth and the model appears on a screen beside you. Nothing has to set in your mouth, and there is no tray to sit still around.
From that model, we map the whole course of treatment out as a sequence of positions. You see where the teeth start and where the plan says they finish.
If the movement your case needs isn’t achievable this way, that shows up here rather than halfway through. It’s the main reason a candidacy answer from a scan is worth more than one from a photograph.
This is also where the awkward questions get answered. How long, how much, what happens if a tooth doesn’t track as planned, and whether anything else needs treating first. Asking all of them is reasonable, and none of them commits you to anything.
What a good candidate walks away with
Straighter teeth without visible brackets is the obvious part. The less obvious part is knowing before you start whether the plan is realistic for your case, and whether 22 hours a day fits the life you actually have.
Both are answerable in one appointment. Whether you’re a good candidate for Invisalign isn’t a judgment call, it’s something the scan shows.
If you want that answer rather than an estimate, request a smile consultation at our office in Rohnert Park. We’ll scan your teeth and show you the plan. No commitment, just a conversation about your options, including the ones that aren’t aligners.
