This article focuses on 3D dental printing. It explains its principle, including layered manufacturing and different techniques. It details the advantages like precision and cost savings. Also, it presents applications in implant, ortho, and restoration. Finally, it explores future trends.
3D Dental Printing Overview
Definition of 3D Dental Printing
3D dental printing is the application of 3D printing technology in the dental field. It is a technology that builds various objects for dentistry, such as dental models and 3D objects related to orthodontic and implant treatments, based on digital model files. It uses bondable materials like powdered metals and plastics and constructs them layer by layer. Compared with traditional dental manufacturing processes, it has many unique features. Traditional processes like machining often have limited forming freedom. In contrast, 3D dental printing adopts the additive manufacturing method, enabling customized production without the need for molds. Moreover, the production time is greatly reduced, which can shorten the dental treatment cycle. It can even be manufactured directly inside the dental clinic.
Importance of 3D Dental Printing
With the development of modern dentistry, patients’ demand for personalized treatment is increasing. Since everyone’s tooth structure and oral shape are different, the traditional manufacturing method of dental products based on standardized molds can hardly meet the personalized needs of many patients. However, 3D dental printing technology can well meet this challenge. It can accurately manufacture the required dental products according to the oral characteristics of each patient, which is of great significance in improving the dental treatment effect and patient satisfaction.
Advantages of 3D Dental Printing
Advantages in Precision and Personalization
High Cutting Precision
In terms of precision, studies have shown that when making resin composite dental crowns, the size precision of DLP 3D-printed dental crowns is higher than that of traditional milling methods. The produced models are more accurate with fewer minute differences. This means that 3D dental printing can achieve more precise manufacturing of dental products. For the production of dental crowns, dentures, models or appliances required for orthodontic treatment, the fit is better and can better adapt to the patient’s oral structure.
Personalization Ability
In terms of personalization, each patient’s tooth shape, arrangement, missing situation and oral size are different. 3D dental printing technology can customize dental products according to different patients’ oral scan data or models. For example, when manufacturing components related to dental implant surgery, implants and abutments can be made according to the specific shape of the patient’s alveolar bone and tooth root. In orthodontic treatment, personalized appliances can be made according to tooth arrangement, whether it is a traditional metal appliance or a transparent invisible appliance.
Advantages in Efficiency and Cost-Effectiveness
Improving Production Efficiency
3D dental printing can greatly improve the production efficiency of dental products. Taking the process of making dental models as an example, the traditional plaster model for making dental crowns and dentures is a manual process, which is slow. And it takes a long time for the model to be ready during the production process. However, 3D printing constructs layer by layer. After importing the intraoral scan data into the 3D printer, the dental model can be output quickly. Especially when making emergency dental models or multiple sets of comparative models, the efficiency improvement is huge. If making temporary dental crowns or bridges, compared with the traditional milling process, it is not only faster but also can quickly obtain the products that meet the needs at a low cost, facilitating patients to receive dental treatment in time.
Reducing Costs
Considering cost-effectiveness, first, it reduces material waste. Traditional dental manufacturing methods such as casting may cause material waste due to factors such as molds and cutting. 3D dental printing adds materials layer by layer based on the required amount, so the material usage is more accurate relatively, reducing material costs. Second, it saves labor costs. For example, in the process of making dental models, the traditional method may require more labor participation. But 3D printing may only require the operator to import the data and perform some simple equipment operations and post-processing, reducing labor expenditure and also improving economic efficiency accordingly.
Application Cases of 3D Dental Printing
Application in Dental Implant Field
Dental Implants and Implant Guides
In the field of dental implants, 3D printing has shown significant advantages. For example, when manufacturing 3D-printed dental implants, the doctor first obtains the medical image data of the patient’s remaining tooth roots and alveolar bone tissue structure. Then, the data for designing the bionic tooth root tissue and the outer structure of the surrounding alveolar bone tissue are extracted from this data to establish a three-dimensional model. After that, the file is transferred to the 3D printing device for physical printing through format conversion.
The implant guide is a key application of 3D printing in dental implants. The surgical guide is a disposable device that can be directly placed on the patient’s teeth. It has holes that specifically guide the implant to be placed at the correct angle and depth. This application solves the problem that it is difficult to place the implant in the correct position due to the inconvenient observation of the internal angle of the mouth during the operation. It makes the placement accuracy of the implant about three times that of manual placement, greatly improving the success rate of dental implant surgery and reducing the risk of complications.
Application in Orthodontics Field
Orthodontic Models and Appliances
In orthodontics, 3D-printed digital models play an important role. In the traditional orthodontic clinical diagnosis and treatment process, the process of making orthodontic models using plaster models is relatively complicated, including multiple processes such as taking impressions with impression materials and plaster casting. Now, tooth data can be obtained through intraoral scanning. Then, the required resin orthodontic models can be made using stereolithography 3D printing technology. Its precision, strength and storability are significantly better than those of plaster models, and the production speed is also faster. Moreover, 3D-printed transparent invisible orthodontic appliances have become an important application direction in the orthodontic field. 3D-printed transparent invisible orthodontic appliances do not require the traditional film pressing operation and can be directly printed. Patients can take them away on the same day, which has overturned the existing production process of orthodontic appliances.
Application in Dental Restoration Field
Dental Crowns, Bridges and Dentures
For the manufacturing of dental crowns and bridges, 3D-printed resin dental crowns and bridges not only have high precision for temporary use but also have good aesthetics. They are also more cost-effective and have a faster production speed than traditional milling processes. In the production of dentures, 3D printing, as an emerging technology, can simplify the production process of dentures and produce dentures in a faster and cheaper way. Although there are currently limitations in aesthetics and low-resolution printers, it is still constantly developing and making progress.
Technical Principles of 3D Dental Printing
Layered Manufacturing Principle
Similar to other 3D printing technologies, the core principle of 3D dental printing is layered manufacturing, also known as additive manufacturing. Its basic operation process is to divide a three-dimensional object model into layers according to a certain thickness. Then, through a computer-controlled printing device, the object is constructed layer by layer. For example, when making a dental model with a complex internal structure, the computer software first divides the digital model of the dental model into layers. Suppose the thickness of each layer is a certain value (such as 0.1 mm). Then, the printer prints according to the shape information of each layer. This layered manufacturing method can produce complex shapes and internal structures that are difficult to achieve by traditional manufacturing methods, such as some dental restorations with fine textures or porous structures.
Different Printing Technology Principles
DLP (Digital Light Processing) Method
The DLP method is a common technology in dental 3D printing. It belongs to a type of stereolithography method. In this method, a projector irradiates ultraviolet light on the liquid resin to harden it. It processes in a planar manner and layers on the surface of the liquid photosensitive resin. So, the layering speed is fast. It can create various complex shapes with high precision and a wide range of size variations of high-definition 3D objects. However, if the DLP method tries to increase the printing area, the resolution will decrease. And there are also large differences in precision brought by different light sources. Some high-end products use 4K projectors to ensure a good printing range and speed.
SLA (Stereolithography Apparatus) Method
The SLA method is also a type of stereolithography method. It irradiates ultraviolet light at a point to harden the photosensitive resin. The difference between this method and the DLP method is that the SLA method irradiates ultraviolet light at one point at a time. This allows it to expand the lamination area. And the device is easier to increase in volume and power generation design. But the lamination time of the SLA method is longer than that of the DLP method. That is, the printing speed is relatively slow.
Inkjet Method
The inkjet method is a modeling method that realizes lamination by spraying powder and exposing it. It is sometimes also called the material injection method. Its layers are formed by stacking points. So, it takes a long time to stack one layer. But the advantage of the inkjet method is that it can stack in a large range. Thus, it can create high-definition and realistic dental objects. For example, some dentures or tooth models with fine surface textures can reproduce the texture of the tooth surface in the mouth more realistically through the inkjet method.
FDM (Fused Deposition Modeling) Method
The FDM method is also called the fused deposition modeling method. It is a method of modeling by melting filamentous materials with heat. In dental 3D printing, for example, when making relatively simple dental models or basic tooth models, the FDM method can be used. It uses filamentous materials such as specific plastic filaments. The filaments are heated and extruded by the nozzle and deposited layer by layer according to the digital model to finally form the shape of the required dental object. Although the FDM method may not have the highest precision among some other methods, its equipment cost is low, the materials are easy to obtain, and the operation is relatively simple.
Future Development Trends of 3D Dental Printing
Technology Improvement and Innovation
Improving Printing Speed and Precision
Future 3D dental printing technology needs to continuously improve printing speed and precision. At present, photopolymerization technologies such as SLA and DLP have achieved certain results in precision, but there is still room for improvement in printing speed. For example, high-speed, layerless restoration photopolymerization 3D printers are considered to be one of the future development directions suitable for the dental industry. With the development of materials science and optical technology, it is expected to develop new resin materials and high-resolution printing light source equipment. This can improve the printing speed while maintaining or further improving the precision, which will be beneficial to the faster and more accurate manufacturing of dental implants and other products with extremely high precision requirements.
Expanding the Range of Applicable Materials
In addition to the currently commonly used materials such as resin, a small amount of metal and ceramic, it is expected to expand the range of 3D dental printing materials in the future. With the diversification of the demand for dental implants, materials such as titanium metal have shown an increasing demand trend in dental 3D printing implants. It may further develop more metal materials with better biocompatibility and excellent mechanical properties for 3D printing dental products. At the same time, some new composite materials may also be developed to manufacture dentures, dental crowns and other products with both aesthetics and functionality. For example, the research and development of composite dental materials with better wear resistance, less discoloration and good matching with tooth structures is expected to continuously make breakthroughs.
Cost Reduction and Application Popularization
Reducing Equipment and Material Costs
From the perspective of cost reduction, if 3D dental printing technology is to be further popularized at present, the equipment cost needs to be reduced. Dental laboratories and individual dentists have a relatively higher acceptance of low-cost photopolymerization systems. With the popularization of 3D printing technology and market competition, relevant equipment manufacturers may adjust the selling price by improving the production process and expanding the production scale to reduce the cost of 3D dental printers. In terms of material cost, with the research and development and large-scale production of new materials, for materials with high cost such as biocompatible resin, it is possible to reduce the material cost, thus reducing the overall cost of 3D dental treatment and enabling more patients to accept the application of 3D printing technology in dental medicine.
Promoting Personalized and Universal Treatment
With the reduction of costs, the personalized advantages of 3D dental printing technology will be more reflected in the oral health treatment of the whole population. For example, in the field of orthodontic treatment, more patients can be provided with personalized customized appliances, not just limited to high-end consumers. In the field of dental restoration, patients with missing teeth will be easier to obtain reasonably priced and personalized dental crowns, dentures and other products. From the perspective of the overall dental treatment market, the application coverage rate of dental 3D printing technology will be increased, truly realizing the comprehensive transformation from traditional dental manufacturing to digital and personalized 3D printing dental manufacturing.
Integration and Intelligent Development
Integrated Development with the Oral Medical Process
In the future, 3D dental printing will be more deeply integrated with the entire oral medical process. It is not only in the current specific dental product manufacturing links. Instead, it starts from the initial examination of patients when they enter the clinic (such as using 3D scanners to collect oral data), to the customization of treatment plans (using computer-aided design software to simulate and design treatment plans with 3D printing data), to the 3D printing of dental objects required during the treatment process (such as dental models, implant guides, etc.) and the subsequent treatment evaluation (comparing the 3D-printed models with the actual treatment effects), forming a complete set of integrated digital oral medical process. This will greatly improve the quality and efficiency of oral medical services and reduce the cumbersome processes and errors in the intermediate links.
Intelligent Auxiliary Diagnosis and Treatment
Intelligence will also become one of the key development trends of 3D dental printing in the future. With the application development of artificial intelligence algorithms in the field of stomatology, 3D dental printing technology can realize auxiliary diagnosis and treatment with the help of intelligent systems. For example, machine learning algorithms can be used to analyze patients’ oral scan data to predict the development trend of dental diseases, so as to formulate a more scientific and reasonable 3D printing dental treatment plan. In the production of appliances, automatic appliance adjustment plans can be made and 3D printed according to the patient’s tooth movement data to improve the correction effect and reduce the number of patient follow-up visits.
