How Invisalign Works: Science Behind Clear Aligners

You want straighter teeth but metal brackets do not appeal to you. Maybe you skipped braces as a teen. Maybe your teeth shifted after years without a retainer. Invisalign is the most asked-about orthodontic option at our Cambridge office. The science behind it is simpler than most patients expect.

Invisalign uses a series of custom clear trays to push teeth into planned spots over time. Each tray differs slightly from the last. It nudges teeth a fraction of a millimetre closer every one to two weeks. The system has treated more than 22 million patients worldwide since 1997, per Align Technology.

Dr. Marwan Elaraby, Dr. Marc Farid, Dr. Ruby Singh, Dr. Lily Barsoum, and Dr. Esraa Mostafa are all certified Invisalign providers at Cambridge Centre Dental Care. We proudly use the iTero Lumina scanner to map each patient’s teeth in 3D. That scan feeds a full treatment plan, including a virtual preview of the result.

Key takeaways about how Invisalign works

Clear trays press on specific teeth in a planned order. The force triggers the same bone changes that braces use to move teeth.
Treatment in Ontario runs $3,500 to $8,500 and lasts 6 to 18 months for most adults.
You wear each tray 20 to 22 hours a day and switch to a new one every one to two weeks.
Invisalign treats crowding, spacing, overbites, underbites, and crossbites. Very severe cases may still need braces.
Cambridge Centre Dental Care offers Invisalign visits seven days a week, with evening hours Monday through Thursday.

How do clear aligners move teeth?

Teeth do not sit fused to the jawbone. They connect through a thin layer called the periodontal ligament. When steady pressure pushes on one side of a tooth, the bone on that side slowly breaks down. New bone forms on the other side to fill the gap. Dentists call this bone remodelling.

Braces use wires to create that force. Invisalign uses trays. The biology is the same. Only the tool is different. Each tray targets one or two teeth at a time while holding the rest still. That control keeps the shifts small and on track.

The force per tray is light, about 50 to 100 grams per tooth, similar to the pressure of resting a finger on a key. That level is enough to trigger bone remodelling without causing pain for most patients.

What are the trays made of?

Invisalign trays use SmartTrack, a BPA-free thermoplastic built by Align Technology. The material is firm enough to push teeth with steady force, yet flexible enough to slide on and off.

Each tray comes from a 3D digital model of your teeth at that exact point in treatment. The fit is snug on purpose. That tight contact creates the push that moves the tooth. As your teeth reach the spot the tray calls for, the pressure eases and the next tray picks up the job.

SmartTrack replaced older plastics in 2013. Clinical testing showed it moved teeth more evenly and cut down on unwanted tipping. Patients also reported better comfort day to day.

What happens at each stage of treatment?

Your first scan and treatment plan

Your dentist takes a full 3D scan of your teeth, bite, and gums. Cambridge Centre Dental Care uses the iTero Lumina. It captures the scan in minutes with no putty mould. The scan flows into ClinCheck, the software that maps how each tooth will shift from start to finish.

You see the projected outcome on screen before any trays arrive. Your dentist adjusts the plan if you want changes, all before anything ships to the lab.

Daily wear and tray changes

You wear each set 20 to 22 hours a day. Take them out to eat, drink anything other than water, and brush your teeth. Most patients swap to a new set every one to two weeks.

Each new tray feels tight for the first day or two. That tightness is the force at work. It fades as the teeth settle. Mild aching is normal at the start of each new set and usually passes within 48 hours.

How attachments and refinements work

Some teeth need extra grip to rotate or tilt. Your dentist bonds small tooth-coloured bumps, called attachments, to specific teeth. The tray clicks onto these bumps and uses them like handles to guide the tooth more precisely.

Near the end of treatment, most patients need one round of extra trays called refinements. These fine-tune any small gaps in the alignment. Refinements are a routine part of the process, not a sign of a problem.

What dental issues can Invisalign treat?

Invisalign handles mild to moderate crowding, spacing, overbites, underbites, crossbites, and open bites. Align Technology says the system now covers about 90 percent of the cases that braces treat.

Severe skeletal jaw issues or very complex tooth rotations may still need wire braces. Your dentist checks your scan and tells you which tool fits your case best. At Cambridge Centre Dental Care, Dr. Marwan Elaraby, Dr. Marc Farid, Dr. Ruby Singh, Dr. Lily Barsoum, and Dr. Esraa Mostafa work with both Invisalign and braces through the orthodontics team, so the goal is the right fit for your teeth, not a sales pitch for one product.

How much does Invisalign cost in Ontario?

Full treatment in Ontario runs $3,500 to $8,500. Mild cases sit at the lower end. Complex bite work lands higher. Most patients fall between $5,000 and $7,500.

Many private plans in Ontario cover Invisalign the same way they cover braces, under the orthodontic benefit. Lifetime ortho maximums usually sit between $1,500 and $3,000. The CDCP does not currently cover adult Invisalign.

Cambridge Centre Dental Care accepts all major plans and offers iFinancing to spread the cost. Ask about your coverage at your first visit so there are no surprises.

Invisalign consultations in Cambridge, seven days a week

Cambridge Centre Dental Care is open seven days a week at 355 Hespeler Road, Unit 218, inside Cambridge Centre Mall near the Cineplex entrance. Dr. Marwan Elaraby, Dr. Marc Farid, Dr. Ruby Singh, Dr. Lily Barsoum, and Dr. Esraa Mostafa are all certified Invisalign providers at Cambridge Centre Dental Care. Evening hours run Monday through Thursday until 7 PM. The team speaks seven languages: English, Arabic, Hindi, Spanish, Urdu, Filipino, and Vietnamese. Parking is free.

If you want to know whether clear aligners can straighten your teeth, call Cambridge Centre Dental Care at 519-624-4640 or book a consultation online. The scan takes minutes. You leave with a clear picture of what treatment looks like for your mouth.