The cumulative effect of error in the digital workflow for complete-arch implant-supported frameworks: An in vitro...

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Digital Dentistry

Background:

• Complete-arch implant-supported prostheses require high accuracy for optimal function and longevity.
• Digital workflows offer potential advantages in fabricating these complex restorations.
• Understanding error accumulation in digital workflows is crucial for clinical success.

Purpose of the Study:

• To quantify and compare error accumulation in complete-digital versus analogue-digital workflows for complete-arch implant framework fabrication.
• To identify specific stages contributing most to inaccuracies in each workflow.

Main Methods:

• Two workflows were evaluated: complete-digital (intraoral scanning) and analogue-digital (conventional casting and laboratory scanning).
• Framework accuracy was assessed using a coordinate measuring machine and inspection software.
• Statistical analysis (Two-way ANOVA) determined the effect of workflow and stage on accuracy.

Main Results:

• Both workflows exhibited expanded uncertainties of approximately 150 μm and 0.8°.
• The Computer-Aided Design (CAD) stage demonstrated the highest accuracy.
• The complete-digital workflow's greatest distortion occurred during data acquisition, while the analogue-digital workflow's occurred during Computer-Aided Manufacturing (CAM).
• The complete-digital workflow showed higher precision in data acquisition but lower trueness at the CAD stage compared to the analogue-digital workflow.

Conclusions:

• Linear distortions were clinically acceptable, but angular distortions were not for either workflow.
• Data acquisition and CAM stages were primary sources of distortion.
• CAD accuracy was influenced by preceding data acquisition errors.
• The analogue-digital workflow demonstrated superior accuracy for complete-arch implant rehabilitation compared to the complete-digital workflow.