Clear aligners look simple and plastic to the untrained eye. In reality, these aligners could be made of a range of materials. Advances in technology have also created new avenues for aligner manufacturers. According to one study, the ideal aligner material should “exhibit high resilience, low hardness, sufficient elasticity, adequate resistance to varied stress and distortion, excellent transparency, low cytotoxicity and high biocompatibility.” 

What are aligners made of?

There are four primary material categories into which aligners fall: 

  • Thermoplastic polymers: These comprise either amorphous or semicrystalline polymers. The former is usually softer and transparent, with good impact resistance, while the latter is harder and more opaque, conferring hardness and rigidity.
  • Polymer blends: Combining amorphous or semicrystalline polymers improves their mechanical properties even more. The proper blending ratio is needed to determine the blend’s ultimate features. One blend may have better mechanical properties, while another could offer better impact or tensile strength.
  • 3D-printed materials: 3D printing has had a considerable impact on the aligner industry. These aligners lower the risk of error and offer improved accuracy overall, reducing costs and manufacturing time. This process uses different materials from traditional fabrication. The results include a better fit, higher mechanical resistance and improved precision.
  • Bioactive materials: The use of bioactive materials is in its infancy, but the goal is to address oral hygiene. For example, one study looked at coating an aligner in gold nanoparticles as an antibacterial defense. Good results have also been seen with cinnamaldehyde.

What does an aligner’s material impact?

Your orthodontist will know the proper material to address your oral care needs. They will consider the following factors when deciding what material works best:

1) Durability

Aligners are worn for an extended period, typically around 1-2 weeks per aligner set and up to 22 hours per day. Choosing aligners made from a durable material that can withstand the pressures of everyday wear and tear is crucial. High-quality aligners made from a durable material can resist cracking, breaking or warping, ensuring they remain effective and intact throughout your treatment.

2) Comfort

Your comfort is key. If you’re uncomfortable for 22 hours a day, you will not keep up with treatment. The material of clear aligners plays a significant role in their comfort. Aligners should fit snugly and smoothly against your teeth. You should not feel any irritation or discomfort. A high-quality, flexible material can guarantee a comfortable fit throughout your treatment. If your gums feel irritated or you notice abrasions, talk to your orthodontist about getting a new material.

3) Transparency

Many people choose aligners because they want discretion that braces don’t provide. Clear aligners are transparent and can be worn daily without being noticed by most people. The material used should be transparent and able to blend in with your natural tooth color. 

4) Cleanliness

Perhaps most importantly, an aligner’s material impacts how you’ll clean it. Aligners that are non-porous and smooth may be best. This material prevents plaque buildup better and may be easier to clean. 

You may be tempted to ignore the specifics of your aligner’s material, but you can’t be blasé about the material when it comes to cleaning. You can damage your aligner if you clean it with a product that doesn’t play well with the material. Talk to your orthodontist about which cleaning products work best for your aligner’s specific material.

Bottom line

An aligner’s material can significantly influence durability, comfort, transparency and cleaning habits. It could even impact how much invisible aligners cost. Be sure to have a comprehensive discussion with your orthodontist so you know how your aligner’s material impacts your treatment path.