Proceedings/Recueil Des Communications Année : 2025

Cobotized intra-oral digitization: a preliminary study

Résumé

This article investigates the potential of using a collaborative robot (cobot) to perform intra-oral scanning for dental applications. In a field where intra-oral scanners (IOS) have revolutionized dental restorations by offering enhanced digital accuracy and patient comfort, manual operation remains highly dependent on the operator's skill. This dependency can lead to inconsistencies in scan quality and may increase the risk of musculoskeletal disorders due to repetitive movements and awkward postures. This study thus explores whether a cobotized approach could reduce operator bias, improve repeatability, and ultimately serve as a valuable teaching tool in dental training. The experimental setup involves a standardized mandibular model based on a 3D-printed anatomical reference. The model is fixed in an articulator simulating an average 45 mm mouth opening to mimic in-vivo conditions. A Dexis IS3800 wireless IOS, chosen for its compact design and ease of use, is mounted on a UR5e cobot fitted with an adaptive gripper. Two scanning trajectories are tested. The first, called the OVL (occlusal-vestibular-lingual) pathway, entails a continuous movement where the scanner first covers the occlusal surface, then the vestibular side, and finally the lingual side of the mandible. The second, the S-shape pathway, involves scanning the three surfaces for each tooth sequentially before moving to the next. To optimize the scanning process and ensure smooth trajectories, a virtual twin of the experimental setup is created using RoboDK. This digital simulation aids in adjusting the scanner's position and orientation while preventing collisions and identifying any non-visible areas that require further attention. For comparison, an experienced practitioner performed manual scans using the OVL pathway under identical experimental conditions. The resulting STL files from both cobotized and manual scans were then analyzed with Zeiss Inspect optical 3D software. The evaluation focused on metrics such as the number of vertices, facets, and the total digitized surface area. In addition, the study introduced two quantitative criteria: the ratio (Rmesh) of the valid scanned area to the nominal mesh and the weighted normalized distance (wND), which measures the volumetric deviation between the scanned and nominal meshes. Although the manual scans produced a slightly larger digitized surface?attributed to the operator's real-time feedback?the cobotized scans exhibited higher point density and lower variability. In terms of accuracy, manual scanning demonstrated marginally better results, but the difference in wND between the two methods was less than 10 µm, a discrepancy deemed clinically acceptable. Overall, the study suggests that while manual scanning may benefit from immediate corrective actions, the cobotized approach offers superior consistency and repeatability. With further optimization in scanner positioning and pathway refinement, cobotized intra-oral digitization shows promise for reducing operator-related errors and fatigue in dental practices, as well as enhancing dental education.

Fichier principal
Vignette du fichier
Colloque_S_MART2025 Review VF.pdf (553.84 Ko) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Licence

Dates et versions

hal-05078657 , version 1 (22-05-2025)
hal-05078657 , version 2 (18-11-2025)

Licence

Identifiants

  • HAL Id : hal-05078657 , version 2

Citer

Floriane Laverne, Rebecca Allport, Lebon Nicolas. Cobotized intra-oral digitization: a preliminary study. 19ème colloque national S.mart 2025, May 2025, Voguë, France. 2025. ⟨hal-05078657v2⟩
154 Consultations
197 Téléchargements

Partager

  • More