Effectiveness of shade selection using the primescan intraoral scanner for communication with the prosthetic laboratory: comparison of accuracy and precision with visual and spectrophotometric methods

• Grant number: 24/16819-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date: August 01, 2025
• End date: July 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Ana Flávia Sanches Borges
• Grantee: Joao Paulo de Souza Borba
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil
• Associated research grant: 23/02207-3 - Evaluation of zirconia reinforced lithium silicate single crowns fabricated in CAD/CAM system: split-mouth randomized controlled clinical trial, AP.R

Abstract

Accurate shade selection in dental rehabilitations is essential for aesthetics and patient satisfaction. Although visual methods, spectrophotometers, and intraoral scanners are widely used, the effectiveness of scanners in communicating shade with the prosthetic laboratory remains uncertain. This study aims to evaluate whether the shade selection tool of the Primescan intraoral scanner and the virtual model it generates are sufficient for laboratory communication and achieving satisfactory shade matching in the fabrication of vitroceramic crowns. Additionally, the accuracy and precision of Primescan will be compared with visual and spectrophotometric methods. A total of 100 single-unit posterior crowns will be fabricated using CAD/CAM technology. Each participant will receive two crowns-one made of lithium disilicate and the other of zirconia-reinforced lithium silicate, randomly assigned, totaling 100 crowns. Shade selection will be performed using visual methods (VITA Classical and VITA Toothguide 3D-MASTER, with and without Smile Lite illumination correction) and instrumental methods (Primescan intraoral scanner and VITA Easyshade spectrophotometer). The only communication with the laboratory will be through the virtual model generated by Primescan and the shade selected by its tool. Final shade matching will be assessed instrumentally (¿E00), by two blinded evaluators, and by patient perception after six months. Accuracy will be determined by the agreement between each method and the spectrophotometer (control), while precision will be assessed based on the consistency of repeated measurements. Statistical analysis will compare the effectiveness of the methods. This study aims to improve clinical protocols, optimizing the aesthetic predictability of dental restorations through enhanced shade selection and efficient communication between clinicians and laboratories.