A Tri-Window Intraoral Scanner (Tri-IOS): design and evaluation

Area of Science:

• Biomedical Engineering
• Dental Technology
• Optical Imaging

Background:

• Traditional mono-window intraoral scanners (Mono-IOS) present challenges in speed and accuracy, particularly for complex dental restorations like edentulous arch implant rehabilitation.
• The cumbersome scanning process and insufficient impression accuracy of current systems hinder clinical efficiency and patient outcomes.

Purpose of the Study:

• To introduce and evaluate a novel tri-window intraoral scanner (Tri-IOS) designed to overcome the limitations of Mono-IOS.
• To enhance impression acquisition speed and accuracy for dental implant rehabilitation through simultaneous multi-directional data capture.

Main Methods:

• The Tri-IOS utilizes a U-shaped configuration with three plane mirrors to create three virtual cameras for simultaneous occlusal, buccal, and lingual data acquisition.
• Calibration of virtual camera relative poses is performed using sphere-based fitting, followed by iterative closest point algorithm for precise point cloud integration, tracking, and reconstruction.

Main Results:

• The Tri-IOS features a compact scanner head and achieves synchronized three-directional data acquisition.
• Impression time was reduced to one-third compared to Mono-IOS setups.
• The Tri-IOS demonstrated enhanced local detail and overall shape fidelity, significantly improving accuracy for edentulous arch implant impressions.

Conclusions:

• The Tri-IOS offers substantial improvements in both the speed and accuracy of dental impression acquisition.
• The mirror-based design facilitates miniaturization and productization, indicating strong potential for clinical adoption.
• This advancement is crucial for enhancing intraoral scanner performance and driving product realization in digital dentistry.