Reliability of a face scanner in measuring the vertical dimension of occlusion

Murali Srinivasan; Florentin Berisha; Innocenzo Bronzino; Porawit Kamnoedboon; Claudio Rodrigues Leles

doi:10.1016/j.jdent.2024.105016

Reliability of a face scanner in measuring the vertical dimension of occlusion

J Dent. 2024 Apr 26:146:105016. doi: 10.1016/j.jdent.2024.105016. Online ahead of print.

Authors

Murali Srinivasan¹, Florentin Berisha², Innocenzo Bronzino², Porawit Kamnoedboon², Claudio Rodrigues Leles³

Affiliations

¹ Clinic of General-, Special Care- and Geriatric Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland. Electronic address: murali.srinivasan@zzm.uzh.ch.
² Clinic of General-, Special Care- and Geriatric Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland.
³ Clinic of General-, Special Care- and Geriatric Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland; School of Dentistry, Federal University of Goias, Goiania, Brazil; Department of Reconstructive Dentistry, Division of Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.

PMID: 38679136
DOI: 10.1016/j.jdent.2024.105016

Abstract

Objective: This study evaluated the reliability of a face scanner in measuring the vertical dimension of occlusion (VDO).

Methods: Fully dentate volunteers (n = 20; mean-age = 30.0 ± 10.7 years) were recruited. Clinical facial measurements were obtained using a digital caliper and a face scanner (Obiscanner, Fifthingenium, Italy). The scans were imported into a mesh-processing software, and the distances were measured digitally. Measurements were obtained for each participant with the jaws positioned in maximal intercuspation (MI) and with increased vertical distances of 2, 4, and 6 mm. Vertical and horizontal measures were obtained using facial anatomical landmarks: Glabella (GL), Pronasale (PrN), Subnasale (SbN), inferior border of the right and left Alare, Labiale superius (Ls), right and left Cheilion (Ch), Soft Pogonion (SPg), right and left Tragus of the ear (Tr), for all selected vertical positions. Data analysis included intra-class correlation coefficient (ICC), pairwise comparison tests, Bland-Altman plots, and Passing-Bablok regression.

Results: 120 VDO measurements (clinical=60, digital=60) were recorded by two independent evaluators. Mean differences between digital and clinical measurements ranged from 0.054 ± 0.14 mm to 0.203 ± 0.13 mm. All parameters were strongly correlated (r > 0.93; p < 0.001). ICC estimates revealed excellent reliability, and the measuring procedure yielded the same results on repeated trials irrespective of the raters and measurement methods. Bland-Altman plots revealed a difference, between digital and clinical measurements, of 1.7 % for the vertical measurements. Regression analysis revealed no significant proportional difference between the two methods, so both can be used interchangeably.

Conclusions: The findings of this study demonstrate that VDO can be measured accurately from face scans using 3D mesh-processing software and that even small changes in the VDO could be detected using the digital methods.

Clinical significance: Findings provide evidence about the reliability of a digital method for jaw relation registrations and may be applied towards incorporating this method into clinical workflows for computer-aided-design/ computer-assisted-manufacturing (CAD-CAM) dentures.

Keywords: 3D Face scan; CAD-CAM complete dentures; Digital complete dentures; Geriatric dentistry; Jaw relations; Removable prosthodontics; Vertical dimension of occlusion.