It is someone belief that the two-step edentulous jaw scanning strategy (i.e. first one side and then the other) is not reliable because, in theory, merging the scans of the 2 sides on the midline could cause alterations in the shape of the arch or a loss of accuracy. This hypothesis has never been proven, indeed today it is definitively denied. based on a scientific study published in the Journal of Prosthetic Dentistry (Lo Russo L, et al. Assessment of distortion of intraoral scans of edentulous mandibular arch made with a 2-step scanning strategy: A clinical study. Journal of Prosthetic Dentistry, 2023, in press), for which was used the Lo Russo Retractors.
Here you are the conclusions of this study:
"1. Intraoral scans of the edentulous mandibular arch made with a 2-step scanning strategy do not ex- hibit significant distortion in comparison with conventional elastomeric impressions.
2. Adequate management of the stability of tissues around the residual ridge, favoring accessibility for the scanner, can yield reliable intraoral scans of the edentulous mandibular arch."
From reading this study it emerges, therefore, that the use of the Lo Russo Retractors and the benefits that derive from it (tissue stabilization, retraction of the tongue and cheeks, improvement of accessibility for the scanner tip), allows the creation of scanning conditions that facilitate and improve the acquisition of the scan and guarantee its accuracy.
Here you can find the preview of the paper.
Enjoy the reading!
The two-step scanning strategy of the edentulous mandible does not cause accuracy problems!