---
title: "How Does Invisalign Work? Step by Step"
description: "How Invisalign works: scan, digital plan, attachments, new aligners every 1–2 weeks, then retainers. Each step explained with timings and London fees."
canonical: https://orthodontistslondon.com/guides/how-does-invisalign-work
last_updated: 2026-10-08
---

# How Does Invisalign Work? A Step-by-Step Guide

Updated 10 October 2026. By Orthodontists London.

Invisalign works by moving your teeth in small planned steps with a series of custom clear plastic aligners, each worn for one to two weeks for about 22 hours a day, until the teeth reach the position set out in a digital treatment plan. Most treatments take 6 to 18 months and finish with retainers.

| Step | What happens | Typical timing |
| --- | --- | --- |
| 1. Consultation | Examination of teeth, gums and bite; photos; X-rays if needed | Week 0 |
| 2. 3D scan | Digital scan of both arches replaces messy impressions | Same day |
| 3. Digital plan | Clinician designs and refines each movement; you see the predicted result | 1–3 weeks |
| 4. Fitting | Attachments bonded; first aligners fitted; instructions given | 3–6 weeks after scan |
| 5. Active treatment | New aligners every 1–2 weeks; reviews every 6–10 weeks | 3–18 months |
| 6. Refinements | New scan and extra aligners if needed | 2–4 months |
| 7. Retention | Retainers fitted to hold the result | Long term |

At [Orthodontists London](https://orthodontistslondon.com/) every Invisalign plan starts with an in-person examination. Adult treatment in London starts from around £2,650, and we give you the total fee in writing before you begin.

## How do aligners actually move teeth?

Teeth sit in bone, held by a thin layer of fibres called the periodontal ligament. When steady, gentle pressure is applied to a tooth, the bone on one side is gradually broken down and new bone forms on the other, and the tooth moves. This is the same biology that makes fixed braces work.

Each aligner is made slightly different from the shape of your teeth at that moment. When you put it in, it fits tightly and presses the teeth towards the next position, usually a fraction of a millimetre. Over a week or two the teeth move to fit the aligner. Then you change to the next set, and the process repeats. A full treatment might involve anything from a handful of aligners to more than 40 per arch.

## What happens at the Invisalign consultation?

We start by asking what you would like to change and checking your dental and medical history. Then we examine your teeth, gums and bite, and take photos and a 3D scan. X-rays are taken where needed, for example to check the roots and bone levels. Gum disease or decay needs treating before teeth are moved, so this check is important.

If aligners suit your case, we explain what they can achieve, how long treatment is likely to take, and what it costs. If fixed braces would work better, we tell you. Our comparison of [Invisalign vs braces](https://orthodontistslondon.com/guides/invisalign-vs-braces) covers the main differences.

## How is the digital plan made?

The 3D scan is used to build a model of your teeth. Software proposes how each tooth could move, step by step, to reach the final position. The proposal is only a starting point: your clinician adjusts it, decides where attachments go, where space is needed, whether elastics are required and how fast each tooth should move.

You usually get to see an animation of the planned movement and the predicted end result before you commit. It is a useful guide, but real teeth do not always follow the plan exactly, which is why refinements exist.

## What are attachments and IPR?

**Attachments** are small tooth-coloured bumps of composite material bonded to some teeth. They give the aligner something to grip and push against, which helps with rotations, vertical movements and bite changes. They are removed at the end of treatment and the teeth are polished.

**IPR (interproximal reduction)** is gentle polishing between some teeth to create small amounts of space, usually a fraction of a millimetre. It is used to relieve crowding without extractions. It is done with fine strips or discs and does not usually need anaesthetic.

## What is daily life like with Invisalign?

| Daily routine | What to do |
| --- | --- |
| Wear time | Around 22 hours a day, including overnight |
| Eating | Take aligners out, eat, brush, put them back |
| Drinks | Only cold water with aligners in |
| Cleaning | Brush teeth and aligners morning and night |
| Changing aligners | Every 1–2 weeks, as instructed |
| Storage | Always in the case when out of your mouth |

The first few days of each new aligner can feel tight, and many people find their speech slightly different for a day or two at the start of treatment. Both settle quickly. Our guides to [whether Invisalign hurts](https://orthodontistslondon.com/guides/does-invisalign-hurt) and [eating, drinking and vaping with Invisalign](https://orthodontistslondon.com/guides/eating-drinking-vaping-invisalign) cover what to expect.

## How often do you see the orthodontist during Invisalign?

Usually every 6 to 10 weeks. At reviews we check that the teeth are tracking, look at how each aligner fits, replace any lost attachments, carry out planned IPR and hand over your next sets of aligners. Some practices use photo-based remote monitoring between visits.

## What are Invisalign refinements?

Towards the end of treatment, or sometimes partway through, a few teeth may not have moved exactly as planned. When aligners stop fitting closely, we take a new scan and order a set of refinement aligners to finish the details. Most comprehensive cases have at least one refinement, which usually adds 2 to 4 months. Check whether your quote includes refinements and for how long.

## What happens when Invisalign treatment ends?

Attachments are removed, the teeth are polished and retainers are fitted. Retainers are essential, because teeth tend to drift after any orthodontic treatment. Most people wear a removable retainer every night for at least a year and then several nights a week long term, or have a thin bonded wire fixed behind the front teeth, or both. Our [retainer cost guide](https://orthodontistslondon.com/guides/retainer-cost) explains the choices.

## Who is Invisalign suitable for?

Aligners suit many adults and teenagers with mild to moderate crowding, gaps, relapse after earlier braces and some bite problems. They are less suitable for severe rotations, large vertical movements and some complex bites, where fixed braces are more predictable. You also need healthy teeth and gums, and the discipline to wear the aligners for about 22 hours a day. The examination is what decides it, not an online quiz.

## How much does Invisalign cost?

In London, adult Invisalign typically starts from around £2,650 in central London and £2,800 in outer London, with comprehensive cases costing more. Across the UK, prices range from about £1,500 for minor cases to £5,500 for comprehensive treatment. See our [Invisalign cost guide](https://orthodontistslondon.com/guides/invisalign-cost-uk) for prices by case type.

## Start with a consultation

If you are wondering whether aligners would work for you, the first step is an examination and a scan. [Request a consultation](https://orthodontistslondon.com/#enquire) through our online form and we will be in touch to arrange it.

## Frequently asked questions

### How does Invisalign straighten teeth?

Each aligner is shaped slightly differently from your current teeth and applies gentle pressure. Bone around the teeth remodels, and the teeth move a small step with each new set.

### How many Invisalign aligners will I need?

It depends on your case. Minor cases may need up to about 10 per arch; comprehensive cases can need 40 or more.

### How often do you change Invisalign aligners?

Usually every one to two weeks, as your clinician instructs.

### Do Invisalign attachments damage teeth?

No. They are bonded to the enamel with tooth-coloured material and polished off at the end of treatment.

### Can you see results from Invisalign straight away?

Most people notice small changes within a few weeks, but the full result takes the whole course of treatment.

## Related guides

- [Invisalign Cost in London: 2026 Prices and What’s Included](https://orthodontistslondon.com/guides/invisalign-cost-london)
- [How Much Do Braces Cost in London? (2026 Price Guide)](https://orthodontistslondon.com/guides/braces-cost-london)
- [Does Invisalign Fix an Overbite?](https://orthodontistslondon.com/guides/does-invisalign-fix-overbite)
- [Does Invisalign Hurt? What to Expect](https://orthodontistslondon.com/guides/does-invisalign-hurt)
- [How Long Does Invisalign Take? Timeline by Case Type](https://orthodontistslondon.com/guides/how-long-does-invisalign-take)
- [London Invisalign and Braces Price Index 2026](https://orthodontistslondon.com/tools/london-invisalign-braces-price-index)
- [Orthodontists in London: Invisalign and braces](https://orthodontistslondon.com/)
- [Areas of London we cover](https://orthodontistslondon.com/london-areas)

Next step

## Talk to a London orthodontist

Tell us what you are looking for and we will be in touch to arrange a consultation. There is no obligation to go ahead.

[Request a consultation](https://orthodontistslondon.com/#enquire)