3D printing and scanning technology make dentistry develop in the direction of digitization. Obviously, appliances such as dental hoops and fixators have become obsolete. The patient's dental anatomical structure does not need to be printed by occlusal mold, but is obtained by scanning, and then the dental model is made by 3D printing. The whole manufacturing process becomes simple and efficient. Many dental clinics send data files to 3D printing laboratories for production, and many dental clinics have their own 3D printers, which can reduce the waiting time of patients and realize real-time production.

But how accurate are these models? This is a question raised by the University of Oklahoma in a paper entitled "accuracy of 3D printed dental models reconstructed from digital dental prints".

"3D modeling and 3D printing are rapidly developing digital technologies in orthodontics, which can transform the traditional clinical workflow into an all digital format," the researchers said. "There is limited literature on the accuracy of 3D printed dental models, and the purpose of this study was to evaluate the accuracy of two 3D printing techniques."

The two 3D printing technologies are DLP (digital light processing) and LCD. In this study, the researchers used the digital and traditional alginate impressions of 30 patients. According to the digital impression, the 3D printing models were made using DLP and LCD technology respectively, and the alginate impressions were poured with stones. Then the measurement results of the three models (DLP and LCD) are compared with the stone model.

The researchers used intra group correlation coefficients based on the results of tooth measurements and arch measurements. "The intra group correlation coefficients of all recorded measurements are high, which indicates that the measurements of all model types are highly reproducible," the researchers said. "Except for the difference in crown height measurement between stone model and DLP model, the height between all models and measurements remains the same."

Therefore, the researchers concluded that digital impression and 3D printing model are completely feasible for clinical application. At the same time, the project also provides a scientific basis for future research and encourages more dental professionals to turn to 3D printing.