In the wave of digital dental diagnosis and treatment revolution, 3D printing resin technology has become the core process in orthodontics, implantation, restoration and other fields by virtue of its micron-level precision, biocompatibility and rapid prototyping ability. This article will systematically analyse the process characteristics and development trend of dental 3D printing resin from the four dimensions of technical principle, material system, process and industry application.
First, the technical principle: precision control of light-curing moulding
Dental 3D printing resin is mainly used in light curing (SLA/DLP) technology, the core principle of which is to irradiate the liquid photosensitive resin with ultraviolet light or laser light, triggering the photopolymerisation reaction so that it can be cured layer by layer.
SLA (Stereolithography): The laser beam scans the surface of the resin point by point, which is suitable for high-precision printing of complex structures, with an accuracy of ±0.025mm, and a layer thickness as low as 25μm, which can accurately restore the details of the occlusal surface of the teeth.
DLP (Digital Light Processing): Curing the entire layer of resin at once through a projector, the printing speed is 3-5 times higher than SLA, suitable for mass production of standardised dental models.
PolyJet technology: combines inkjet and light curing, supports multi-material hybrid printing, and can simultaneously achieve the integration of rigid structures and flexible supports, but with higher equipment costs.
Key Advantage:
Mould-less manufacturing: generates solids directly from digital models, eliminating the traditional gypsum mould-turning step and reducing manual errors.
Surface quality: the surface of the printed part is smooth and does not require post-polishing to meet clinical use standards.
Material utilisation: curing on demand, material waste rate is less than 5%, in line with the trend of green manufacturing.
Second, the material system: biocompatibility and functional breakthroughs
Dental 3D printing resin needs to meet the ISO 10993 biocompatibility certification, and at the same time develop special materials for different clinical needs:
Standard model resin: used for making diagnostic models and orthodontic dental models, with an accuracy of ±0.05mm, moderate hardness (Shore hardness 80-90D), and long-term preservation.
High-temperature-resistant resin: resistant to high temperature of 120℃, suitable for casting metal restorations in the melt mould production, low coefficient of thermal expansion, casting high precision.
Flexible resin: adjustable modulus of elasticity (0.5-2GPa), used for making invisible orthodontic appliances and jaw pads, with high wearing comfort.
Anti-bacterial resin: silver ion or nano titanium dioxide is added to inhibit the growth of oral bacteria and reduce the risk of secondary caries.
Transparent guide resin: light transmittance >90%, used for implant surgery guide, can achieve accurate navigation through CBCT image.
Examples of material innovations:
Kexcelled Dental Series: Introducing low odour and low ash resins with cast surface roughness Ra <0.8μm, reducing the subsequent polishing process.
Graphy TC-85 biomaterial: elasticity range of 300%-400%, force attenuation rate reduced by 60% compared with traditional PETG material, suitable for long-term wear of invisible aligners.
C. Process Flow: Full chain control from data to entity
The process flow of dental 3D printing resin covers data acquisition, model design, printing parameter optimisation and post-processing:
Data Acquisition:
Intraoral scanners (e.g. 3Shape TRIOS, iTero) acquire 3D data of patient's teeth with an accuracy of ±0.02mm.
CBCT scans the alveolar bone structure for implant guide design.
Model design:
Use dental CAD software (e.g. exocad, DentalCAD) for restorative morphology design, occlusal relationship adjustment.
Generate STL format file and set printing parameters (layer thickness, exposure time, support structure).
3D Printing:
Preheat the resin bath to 25-30°C to reduce viscosity and enhance fluidity.
Real-time monitoring of the curing degree between layers during printing to avoid deformation caused by under or over curing.
Post-treatment:
Alcohol cleaning to remove uncured resin, ultrasonic cleaning for 5 minutes to ensure clean surface.
UV light curing box secondary curing (405nm wavelength, 10-15 minutes), to enhance the mechanical properties of the material.
Support structure removal, edge trimming, the final precision needs to meet the clinically acceptable error range (orthodontic model ≤ 0.25mm, implant guide plate ≤ 0.1mm).
Fourth, industry applications: from auxiliary tools to standardised production
Dental 3D printing resin has penetrated
