The AAO’s 2024 member technology survey indicated 43% of members use 3D printers and of those, 96% use their printers to produce retainers while 55% use 3D printers for models for limited clear aligner cases. Dr. Tarek ElShebiny, a member of the AAO Committee on Technology (CTech), also examined these questions in research published in the AJO-DO.

“The results of our Case Western Reserve University study evaluating the uses of 3D printing technology in orthodontic offices across North America closely aligned with the AAO data: Orthodontists primarily used their 3D printers to fabricate plastic retainers from printed models,” says Dr. ElShebiny.

The researchers found that space for equipment/ventilation, digital workflow training deficits, and lack of manpower were major factors preventing orthodontists from incorporating in-office 3D printing.1

“Increasing patient load and being in private practice significantly increased the probability of having a 3D printer,” says Dr. ElShebiny. “These findings support what I observe informally among colleagues: Almost every orthodontist who adopts 3D printing begins with retainer production, because it provides an immediate return on investment and dramatically shortens turnaround time. Limited in-house aligner fabrication is growing as well, but at a slower pace due to additional workflow and training needs.”

In private practice since 2018 near Cleveland, Ohio while continuing to serve as a clinical assistant professor in the Case Western orthodontic program, Dr. ElShebiny purchased his first 3D printer soon after opening his practice and began with printing models for in-house retainer production.

“Several factors influenced my decision to produce retainers in-house, especially cost-effectiveness and speed,” he says. “In-office production significantly lowered lab costs and allowed us to streamline workflow and deliver retainers more efficiently.”

Product Selection Combines Technical and Practical Factors
When selecting a printer for in-house retainer production, Dr. ElShebiny compared stereolithography (SLA) versus digital light processing (DLP) technology.

“These factors determine the accuracy, surface quality, and speed of the prints,” he says. “I also evaluated the size of the build platform, because a larger platform allows more models to be printed at once. Another important consideration was whether the system was open or closed with regard to compatible resins, as this affects flexibility and long-term cost. Budget always plays a role as well.

“Ultimately, I chose printers that offered higher accuracy, faster printing speed, and the largest feasible platform within a reasonable budget,” he says.

Lab set-up for retainer production requires additional equipment including a washer and curing unit to ensure all excess resin is removed and each model is fully post-processed. Dr. ElShebiny recommends investing in a complete system that includes the printer, a wash station, and a curing unit to keep the workflow efficient and predictable.

If you are considering new or replacement products for in-house retainer production, visit AAO Tech Select for side-by-side comparisons of product features from leading manufacturers, including 3D printers and intraoral scanners.

Innovative Step Allows for Retainer Production and Delivery at Debonding
“A major part of our practice workflow involves scanning patients while they still have fixed appliances or clear aligner attachments, then virtually removing the brackets or attachments before printing the models and fabricating the retainers,” says Dr. ElShebiny.

“This virtual-removal process is something we studied and validated in research at Case Western.2

“In many cases, we are able to remove the fixed appliances and deliver the retainer all in the same visit, which dramatically enhances efficiency and improves the patient experience,” he adds. “Our digital workflow evolved particularly for virtual removal of brackets or attachments and the transition from scanning to printing. Staff training was essential and standardizing steps for trimming, labeling, and preparing models helped ensure reproducibility across the team.”

The system’s evolution was a journey for Dr. ElShebiny’s practice. When in-house retainer production began, they fabricated only about 20% of retainers.

“Each month, we increased production by another 20% until we fully transitioned to 100% in-house retainers,” he says. “After that, we expanded into in-house aligner fabrication, beginning with minor crowding, spacing, and replacement trays. We eventually progressed to more complex cases, but careful case selection is essential to ensure the workflow remains efficient and cost-effective.”

Recommended fine-tuning of workflow steps includes:

  • Optimization of layer thickness. “Layer thickness directly affects both model accuracy and the fit of thermoformed retainers,” says Dr. ElShebiny. “This was supported by our research (The influence of 3-dimensional printing layer thickness on model accuracy and the perceived fit of thermoformed retainers).”3
  • Adjustment of print orientation and model positioning. “These steps improve accuracy and reduce print time,” says Dr. ElShebiny.
  • Post-processing refinements. “These include ensuring thorough washing and consistent curing, so the models maintain their dimensional stability,” says Dr. ElShebiny.

In addition, scheduling should ideally coordinate 3D printing time blocks with debonding appointments.

“Schedule coordination ensures reliable production of retainers for debonding day,” says Dr. ElShebiny. “Collectively, all of these workflow refinements have improved efficiency and consistency across our in-house production system.”

AAO TechSelect offer guidance on producing in-house retainers, including a breakdown of fabrication steps.
Learn more by visiting TechSelect, which features detailed product comparison points and workflow steps for complex products including 3D printers and scanners. Product categories also include digital indirect bonding and custom bracket systems, remote monitoring, robotics and tooth movement software. Dr. ElShebiny and his colleagues on AAO CTech vet participating TechSelect partner companies and their products.

1. The uses of 3-dimensional printing technology in orthodontic offices in North America. American Journal of Orthodontics and Dentofacial Orthopedics, 2024;166(1):76–80. doi: 10.1016/j.ajodo.2024.03.014

2. Assessment of virtual bracket removal by artificial intelligence and thermoplastic retainer fit (ElShebiny, T. et al., American Journal of Orthodontics and Dentofacial Orthopedics, 2024;166(6):608–615).

3. The influence of 3-dimensional printing layer thickness on model accuracy and the perceived fit of thermoformed retainers (ElShebiny, T. et al., American Journal of Orthodontics and Dentofacial Orthopedics, 2025;167(4):490–498.e3).