The best clear aligner material
- Jesper Hatt DDS
- Aug 23
- 6 min read
Every dentist wants the “secret sauce” behind the best clear aligner material - whether it’s PETG’s crystal clarity, SmartTrack®’s gentle resilience, or the futuristic promise of 3D‑printed resins. I get it, and I understand why I hear this question every week. In this post, you’ll get:
A side‑by‑side comparison of today’s leading aligner plastics: their strengths, weaknesses, and ideal use cases.
Insights on soft vs. hard durometers: why flexible sheets excel at crown tipping and rigid trays rule root control.
An inside look at 3D‑printed aligners: the game‑changing possibilities and the real‑world complexities you need to know.
A reality check on material obsession: why focusing on plastic first can leave you chasing marginal gains and what to tackle before you swap one tray for another.
A step‑by‑step guide to matching your chosen material (and trimline design) to your optimized workflow, software platform and local support network.
Read on to discover which aligner materials shine in specific scenarios and why mastering your planning, software and service foundations will always deliver the most dramatic improvements to your outcomes.
Proven classics: PETG & TPU (SmartTrack®)
PETG (Polyethylene Terephthalate Glycol): Widely used in early aligners (e.g., EX30®), PETG boasts excellent transparency and rigidity, ensuring crisp tooth movements. Its mechanical and optical properties make it a reliable choice for predictable staging PMC.
SmartTrack® (Thermoplastic Polyurethane): Introduced by Invisalign in 2013, SmartTrack® improved elasticity and recovery over PETG, delivering smoother seating and gentler forces. Clinical studies show its multi‑layer PU structure enhances comfort and control, speeding up tooth movement with fewer mid‑treatment tweaks Diamond BracesPMC.
Key point: Whether you choose PETG or TPU, both conventional materials can achieve excellent results, so long as your staging, attachments and biomechanics are spot on.
Soft vs. hard aligner polymers: Crown movement vs. root control
When selecting an aligner material, understanding its mechanical properties is key to predictable outcomes. Clinical and in‑vitro evidence suggests that softer, low‑durometer sheets excel at tipping crowns, while stiffer, high‑durometer materials are superior at guiding root movements.
Crown movement: Soft, flexible sheets
Low‑durometer PET‑G or TPU blends (thickness ≈ 0.5 mm) allow gentle, continuous forces ideal for controlled tipping and minor rotations.
Study findings: In one in‑vitro trial, thin PET‑G aligners induced an average 2.8 mm incisal edge displacement with almost no root apex movement (–0.2 mm) over the test period afjbs.com. This “pure tipping” action is valuable for fine‑tuning crown positions without over‑stressing the periodontal ligament.
Pros:
Increased patient comfort and ease of seating
Lower insertion forces reduce soreness
Effective for simple alignment and finishing movements
Cons:
Insufficient stiffness for bodily translation or torque
Greater risk of unwanted relapse if over‑relied upon
Ready to take your aligner treatments to the next level?
Discover expert strategies, step-by-step guidance, and proven methods for mastering aligner orthodontics in our new book, Mastering Aligner Orthodontics. Whether you're using SureSmile, Invisalign or another major aligner system, this book is your ultimate resource for achieving predictable, profitable results. From diagnosis and treatment planning to digital planning with either SureSmile, Invisalign, ClearCorrect or Spark including "how to" guides for every system - it is all covered in the book.
Empower your practice and deliver the exceptional care your patients deserve.
Root Movement: Hard, Rigid Sheets
High‑durometer materials (thickness ≥ 0.75 mm) such as advanced PET‑G or multi‑layer TPU (SmartTrack®) generate the moment couples necessary for true root torque and bodily translation.
Study findings: Thicker PET‑G aligners produced significant root movement (1.2 mm) with minimal crown shift (–0.1 mm), demonstrating effective root control (p < 0.001) afjbs.com.
Pros:
Precise control of root angulation and bodily movements
Maintains form over longer wear cycles
Improves staging accuracy
Cons:
Firmer aligners can feel bulkier and may require refined trimming
Higher insertion forces can increase initial discomfort
Balancing Comfort and Control
Some practices benefit from a hybrid approach:
Initial crown alignment with softer, thinner trays to boost patient compliance and rapid tipping movements.
Subsequent root torque and bodily shifts using a firmer, thicker material to lock in deep‑seated movements.
By matching material stiffness to the specific movement goal - tipping vs. torque - you may harness the best of both worlds: patient comfort and biological efficacy. It is worth considering trimline design as well as it plays a major role in force transmission.
2. The 3D‑Printing frontier
3D‑printed aligners promise on‑demand production and innovative designs—variable thickness zones, built‑in hooks or pressure points. Early research shows printed aligners can match—and sometimes exceed—the trueness and precision of thermoformed sheets (0.140 mm vs. 0.209 mm RMS error) sweeth.pro.
But in practice, 3D printers add complexity:
Lab investment & training: You need an in‑house lab and a dedicated technician.
Handling risks: Resins can be allergenic and require strict safety protocols.
Software gaps: No current platform fully leverages zone‑specific thickness or integrated attachments. Add to that the challenges related to data transfer from the scanner to the planning software and from the planning software to the printing software. Currently we have observed significant challenges in this regard.
Material stability: Long‑term durability still lags behind established thermoformers PMCFrontiers.
The Clear Aligner material isn’t magic - Planning is!
Imagine blaming a flimsy aligner when a case derails. In reality, even the most advanced plastic with an ideal trimline design and changing physical proportions, can’t rescue a plan that overlooks root angulation, bone support or patient compliance.
The three pillars of predictable treatment are:
Accurate Diagnosis & Realistic Planning: Your ability to identify red flags, stage movements and sequence biomechanics is paramount.
Patient Communication & Compliance: No plastic will compensate for a patient who skips wear time. Clear expectations and motivational support are essential.
Precision Execution: Once your plan is solid, any reputable material, whether PETG, SmartTrack® or a printed resin, can deliver the outcome you designed.
Receive more free tips and tricks for your clear aligner treatments. Follow us on LinkedIn:
Matching material to your workflow
Even the most advanced material can’t deliver predictable results without the right platform and support. Start by choosing an aligner system whose software lets you:
Precisely modify movements (translation, rotation, torque) and fine‑tune staging speed to respect biological limits.
Customise attachments, cutouts and pressure points directly in your 3D setup - no clumsy workarounds.
Control movement velocity so you avoid over‑ambitious shifts that can stress bone or soft tissue.
Segment teeth with surgical accuracy, ensuring that both roots and crowns follow your intended paths.
When your digital plan flows seamlessly through scan ingestion, model alignment, tooth segmentation, prescription editing and final tray production - all under one calibrated industry standard - you’ll see:
Fewer mid‑course corrections
Less time removing old attachments and bonding new ones
Higher first‑pass tracking rates
Equally crucial is local support. Material choice is only a fraction of the equation; delays, production errors, software glitches or integration hiccups can grind your workflow to a halt. A partner with on‑the‑ground service teams solves delivery issues, answers design questions, manages software updates and smooths integrations, so you never waste time or risk patient trust.
Master your clinical diagnosis, orthodontic treatment planning and staging strategy first, then let the right material, platform and local support align perfectly with your workflow for consistently efficient, successful treatments.
Develop deep expertise with One aligner brand
Finally, commit to a single aligner system long enough to truly master its nuances. As you treat dozens, or even hundreds, of cases with the same platform, you’ll uncover its strengths, recognise its limitations, and learn clever workarounds that ensure consistently predictable outcomes.
Once you’ve delivered 200+ cases using one brand, you’ll have the clinical confidence and operational insight needed to explore alternative systems. Fully aware of the criteria required to hit your treatment goals every time.
The best clear aligner material in summary
No single plastic holds the secret to flawless aligner outcomes. PETG and SmartTrack® sheets both deliver reliable performance, and 3D‑printed resins hint at tomorrow’s innovations. But none can compensate for a missing diagnosis, a poorly staged plan or a disengaged patient. Predictable success comes from mastering the clinical fundamentals: accurate case selection, realistic biomechanics, clear patient communication and pairing them with a robust software platform and dependable local support. Nail these core elements first, and any well‑chosen material will faithfully bring your virtual plan to life.
If you found this deep dive helpful, subscribe to the AlignerService blog for more insider tips on clear‑aligner treatments. You’ll receive 1–2 concise updates each month—no fluff, just the strategies and shortcuts you need to plan and execute with confidence.
Kind regards
Jesper Hatt DDS
P: +41 78 268 00 78
AlignerService
We are dentists helping dentists create realistic, safe and predictable treatment plans with clear aligners.
Currently more than1500 dental practices in 19 different countries use our service on a regular basis. We offer expert guidance in the following clear aligner systems: Invisalign, SureSmile, ClearCorrect, TrioClear, Angel Aligners and Spark.
AlignerService is a preferred partner of ClearCorrect and TrioClear.