Over the past two decades, the dental industry has witnessed the emergence of subtractive manufacturing technologies, particularly milling machines. CAD software has become both reliable and accessible to most dental laboratories. However, a new contender has emerged to challenge the technological superiority of milling: additive manufacturing, or 3D printing.
While this technological evolution was initially seen in the production of fixed prosthetics, it has gradually made its way into the realm of removable prosthetics. Though its adoption was initially slow, the growing demand for digital solutions for removable prosthetics has driven manufacturers to find the ideal combination of materials and 3D printing technology.
For decades, the gold standard in prosthetic fabrication was manual manufacturing with a high degree of reliability. However, this new technology—whether additive or subtractive—has proven capable of surpassing this trusted method, offering the best combination of scalability, aesthetics, cost, and strength. Initially, the limited availability of consumables restricted manufacturers to subtractive methods, but with advancements in 3D printing accuracy and the development of new printable polymers, the next generation holds promise for groundbreaking solutions. Every laboratory has different needs and priorities. In this article, we attempt to compare aesthetics, strength, manufacturing techniques, costs, and the impact of both methods in dental laboratories.
Aesthetics
Initially, the biggest difference between milled and 3D printed dentures was the appearance, largely due to the quality of the printing materials. Early 3D printing materials were often translucent and brittle, resulting in weak and unattractive prosthetics. The biggest challenge was hiding the underlying dental structures at the Cemento-Enamel Junction (CEJ) areas. Many of these early printed prosthetics required labor-intensive external coloring to achieve a satisfactory appearance. However, with the introduction of newer printable polymers, the playing field has been leveled once again. Today, neither method requires external coloring to achieve enhanced aesthetics.
Time and Labor Costs
One of the most significant benefits of entering the digital realm is the increased efficiency it provides. This capability allows for higher production levels without sacrificing product quality. As in most industries, labor is not only the largest expense but also the most valuable asset. Even in this constantly evolving digital landscape, artistry remains the distinguishing factor between a top-tier product and an average one. Digital tools will never replace true craftsmanship, but they provide 21st-century dental labs with the means to increase profitability.
In some laboratories, it has been demonstrated that subtractive methods require 38% less manual processing time compared to analog methods, resulting in a 39% reduction in labor costs per denture. Similarly, 3D printing has been shown to reduce manual processing time by 47% compared to analog methods, leading to a 49% reduction in labor costs per denture. While 3D printing is very similar to milling, it requires 13% less manual processing time, which translates to an 18% savings in labor costs.
Equipment Processing Time
Most 3D printing technologies consistently outperform subtractive methods in terms of production efficiency. To translate this efficiency into a return on investment, it is essential to consider the impact of equipment costs on the overall production cost. The contribution of equipment costs to the final product price is influenced by two factors: the cost of the equipment and the number of units that can be produced in a given time. Equipment costs can only be offset by production capacity. Thus, the equation of units produced per day versus equipment costs plays a key role in calculating your potential return on investment.
Milling vs. 3D Printing Options
Milling offers several options for integrating dental structures with the prosthetic base. Pre-made and custom-made dental structures enable the use of milling even in cases with severely reduced vertical space.
Final Thoughts
Upon evaluating the data on costs, workflow, material properties, and other relevant factors, it becomes clear that this comparison between the two methods is not straightforward. Both systems share most of the positive characteristics of the final product, but the technological weaknesses can make a significant difference in process efficiency.
Both systems are capable of producing strong, aesthetically pleasing prosthetics using a fully digital workflow, without the need for extensive manual processing. Due to the variety of available dental structures, the milling method allows for the production of milled prosthetics for almost all edentulous patients. Having multiple dental structure options enables the technician to execute multiple solutions while considering numerous clinical factors.
However, the inherent limitations of the milling process significantly restrict the production capabilities of the equipment. This limitation also holds true for production volumes. Even if we compare a fully assembled dental and base prosthetic produced through milling to one created through 3D printing, the production volume limitation means that producing larger quantities would require multiple expensive milling units. Therefore, in the end, products must be priced higher to maintain profitability. On the other hand, 3D printing has its limitations, mainly due to the lack of a customizable dental structure and pre-made options. A single printed tooth, even a premium one, may not meet all of the aesthetic demands of clinicians. Ultimately, the advantage that 3D printing offers over milling is the significant scalability and cost savings that come with high-volume production.
That said, each laboratory is unique and prioritizes its own set of criteria. While these two technologies are vastly different, they both produce remarkably similar products. The only question that remains is: which one is right for you?
