Are braces stronger than aligners?

Yes. Braces exert continuous 3D force (torque) directly onto the tooth and root via a rigid wire, making them biomechanically stronger and more predictable for complex movements compared to the pushing force of flexible plastic aligners.

Can aligners fix a severe overbite or deep bite?

While aligners can improve mild to moderate overbites using attachments and elastics, severe deep bites or skeletal discrepancies typically require the robust vertical control and heavy elastics that only traditional fixed braces can provide.

Do orthodontists prefer braces for complex cases?

Absolutely. For severe crowding, impacted teeth, or large extraction space closures, board-certified orthodontists generally prefer traditional braces due to their precise root control and lack of dependence on patient compliance.

Is Invisalign effective for Class II malocclusions?

Invisalign can be effective for mild to moderate Class II cases, often using mandibular advancement features or elastics. However, severe Class II skeletal issues are less predictably treated with plastic trays alone.

Braces vs. Aligners: A Decision Matrix Based on Clinical Complexity

By Senior Orthodontic Consultant

Updated: 2026

Clinical Case Review

If you search the internet for “Braces vs. Aligners,” 99% of the articles will ask you two questions: “Which is cheaper?” and “Which looks better?” These are the wrong questions.

“Orthodontic treatment choice should be based on biomechanical complexity, not marketing preference.”

The real question you must ask your orthodontist is: “Is my clinical case actually suitable for clear aligners?” While plastic trays are fantastic, they have distinct biological and mechanical limits. Today, we step away from the marketing hype and look at the raw clinical data.

What Determines Clinical Complexity?

Orthodontists don’t just look at crooked teeth; they measure the geometry of your bite. According to standards utilized by the American Association of Orthodontists (AAO), case complexity is determined by:

Severity of crowding: Measured in millimeters (e.g., >8mm is severe).
Vertical issues: Severe Overbites (Deep bite) or Open bites.
Tooth Rotations: Canines or premolars rotated more than 20 degrees.
Skeletal discrepancies: Issues rooted in the jawbone length, not just the teeth.
Impacted teeth: Teeth trapped under the gums requiring forced eruption.

The Biomechanics: Brackets vs. Plastic Trays

To understand why certain cases fail with aligners, we must look at physics.

Traditional Braces

Because brackets are glued directly to the tooth and connected by a rigid wire, they provide true 3D control. They excel at “torque expression”—meaning they can grab a tooth and physically drag its hidden root through the jawbone predictably.

Clear Aligners

Aligners push teeth. They have limited torque control because plastic flexes. To grip a round tooth, they depend heavily on “attachments” (composite bumps glued to your teeth). Even then, complex root movements are mathematically less predictable.

*Clinical Example: A severe Class II malocclusion with a vertical component (deep bite) often overwhelms the pushing capacity of plastic trays, requiring the heavy elastic force systems unique to fixed braces.

The Clinical Decision Matrix

Use this matrix as a baseline reference before consulting your doctor.

Clinical Case Type	Metal/Ceramic Braces	Clear Aligners	General Recommendation
Mild crowding (< 4mm)	Excellent	Excellent	Either (Patient Preference)
Moderate crowding (4–8mm)	Excellent	Good	Case-dependent
Severe crowding (> 8mm)	Excellent	Limited	Braces Preferred
Deep Bite / Overbite	Excellent	Moderate	Often Braces
Skeletal Class III (Underbite)	Necessary	Rarely Sufficient	Braces + Surgical Plan

Real-World Limitations of Aligners

While AI digital scans create beautiful 3D simulations of aligner results, reality doesn’t always match the computer. Limitations include:

Predictability vs Simulation: Teeth are anchored in living bone, not pixels. A tooth may simply refuse to rotate with a plastic tray.
Refinement Stages: Most aligner patients need “refinements”—scanning the teeth again and ordering more trays because the teeth stopped “tracking” the original plan.
Compliance Failures: If you don’t wear them 22 hours a day, they fail. Period.
Attachments Visibility: To move difficult teeth, doctors glue many attachments to your front teeth, making them far less “invisible” than advertised.

Cost vs. Clinical Outcome

Choosing aligners for a severe case to avoid metal can backfire financially. If the aligners fail to achieve the complex movements required, you face Retreatment Cost. You may end up paying for aligners, only to switch to braces mid-treatment to finish the job. Understanding true treatment costs involves assessing predictability, not just the initial quote.

When Aligners Are Truly Ideal

We are not attacking aligners; they are brilliant tools when used correctly. They are the absolute best choice for:

Mild Relapse Cases: You wore braces as a teen but lost your retainer.
Adult Aesthetic Priority: Mild to moderate crowding where aesthetics matter more than perfect biomechanical speed.
Busy Professionals: Fewer emergency visits for broken wires.

The Final Word

Orthodontics is controlled force application, not a cosmetic accessory choice.

If your doctor recommends braces over aligners, it is likely because your roots and jawbone require 3D control that plastic cannot provide. Trust the biomechanics.

Read Our Ultimate Metal vs Invisalign Showdown

Medical Disclaimer: This article serves as an educational resource to explain orthodontic biomechanics. It does not constitute a medical diagnosis. Case complexity and treatment suitability must be determined by an in-person clinical exam and radiographic analysis by a licensed, board-certified orthodontist.

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