Registering intraoral scans, facial scans and CBCT as multimodal 3D data is a major pain point in digital dentistry. If data from different devices, coordinate systems and formats cannot be aligned in one space, downstream smile design, implant guides and orthognathic simulation are hard to connect.
Why registration is difficult
Intraoral scanning captures the dentition and mucosa, facial scanning captures soft-tissue contours, and CBCT captures bone and tooth roots. Each dataset has its strengths and its own coordinate system. Traditionally, clinicians import data between several programs and align it by hand, which depends on experience and is hard to reuse.
Registration is not just about overlaying two images. It keeps bone, teeth and face consistent within one spatial coordinate system so they can be called up at any point in later design work.
One workflow: from split-screen landmark selection to automatic registration
The system quickly registers bone, tooth and facial 3D data during diagnosis and treatment, building a digital virtual patient without switching between several programs.
In practice, the system offers split-screen display and anatomical landmark selection. The intelligent registration algorithm calculates and selects the optimal spatial position, matching the intraoral scan with the CBCT and facial scan. Clinicians only confirm the key landmarks; the alignment calculation is left to the algorithm.
Three practical capabilities
Point 01 | Bone-to-surface distance measurement: users can select two points on the facial soft-tissue model and the CT hard-tissue model, and the system automatically calculates the Euclidean distance between them to 0.1mm. The value can be used to observe the thickness relationship between bone and soft tissue.
Point 02 | Smile aesthetic simulation: 3D dynamic lip-line extraction traces the smile curve, and dynamic facial cropping and fusion overlay the intraoral model on the facial smile model to preview how teeth and lips fit together.
Point 03 | Integrated composite model export: after intraoral scan, 3D facial scan and cone-beam CT data are registered, the bone and upper and lower jaw 3D models can be exported in one step within the same spatial coordinate system, compatible with STL, OBJ and PLY, for import into third-party orthodontic, implant guide and restorative design software.
Which devices it works with
Registration ultimately depends on the capture device. In oral and maxillofacial settings, for example, the MVS-P6HD offers 3D measurement accuracy of ±0.05mm and volume measurement accuracy of ±0.05ml, with a full scan in under 2 seconds and support for DICOM, STL and PLY input, suited to orthodontic, orthognathic and restorative design work with high accuracy requirements.
Where dynamic expressions and soft-tissue change are involved, the MVS-C4D captures at 16fps with 3D measurement accuracy of ±0.1mm and also supports DICOM import, recording smiling, speaking and other dynamic processes; the MVS-C6HD offers ±0.1mm accuracy and DICOM support for routine oral and maxillofacial scanning. Available functions depend on model and software configuration.
The CASZM multimodal oral 3D data registration system centers on intelligent registration, distance measurement, dynamic smile simulation and integrated model export, helping fuse soft- and hard-tissue data in one coordinate system as a reference for digital dental design.
This article is based on a CASZM WeChat article. View the original article