Development of a digital impression procedure using photogrammetry for complete denture fabrication.

Area of Science:

• Dentistry
• Digital Imaging
• Biomedical Engineering

Background:

• Digitizing dental anatomy is crucial for prosthodontics.
• Conventional impressions can be time-consuming and introduce inaccuracies.
• Photogrammetry offers a novel approach for 3D model creation from 2D images.

Purpose of the Study:

• To validate the effectiveness of a photogrammetric system for digitizing maxillary edentulous residual ridges.
• To compare the accuracy of photogrammetric digital impressions with conventional methods.

Main Methods:

• Maxillary residual ridges of five edentulous patients were impressed using three conventional methods and one photogrammetric system.
• Conventional impressions were used to create plaster models, which were then digitized.
• Three-dimensional (3D) forms from all methods were superimposed and analyzed for differences using a least squares best fit algorithm.

Main Results:

• Optimal imaging conditions for the photogrammetric system were identified as ±15 degrees horizontally and 45 degrees vertically.
• The photogrammetric system (Form A) showed a mean difference of 0.52 ± 0.22 mm compared to a preliminary conventional impression (Form C).
• Differences between the photogrammetric system and conventional final impressions (Forms B and D) were significantly smaller (0.26 ± 0.06 mm and 0.25 ± 0.07 mm, respectively).

Conclusions:

• Photogrammetric system demonstrates feasibility for clinical application in dentistry.
• The system provides a viable method for obtaining digital impressions of edentulous residual ridges.
• Further research may refine imaging protocols for enhanced accuracy.