Spectrophotometric measurements and its correlation to human eye color perception. Influence of white/black vs. Cuspal/non cuspal backgrounds on tooth color assessment

BACKGROUND: The aim of this in vivo study was to compare spectrophotometric backgrounds - white (WB) with cuspal (C), black (BB) with non cuspal (NC) - in order to determine if the oral natural conditions could be used as reliable backgrounds instead of the traditional black and/or white for in vivo color matching. Methods: Spectrophotometric measurements were performed on ninety-three upper right permanent central incisor. Among inclusion criteria were A1, A2, A3 (Vita Classical scale) tooth shade. Each tooth was measured on black, white, cuspal and non cuspal backgrounds. ΔE between black and non cuspal (ΔEBBNC) and ΔE between white and cuspal (ΔEWBC) were calculated and correlated to human eye color perception (AT, PT). Opalescence (O) and contrast ratio (CR) were calculated on the four different backgrounds. Results: The comparison between black and oral cavity natural backgrounds shows high clinical acceptability: 98.9% in the central, 96.8% in the gingival and 92.4% in the incisal tooth area. Clinical acceptability between white and oral cuspal backgrounds was 90.3% in the gingival, 79.6% in the central and 7.6% in the incisal tooth area. CONCLUSIONS: Natural oral black background can always be used instead of the artificial one, while the natural bright oral background can be used instead of the artificial one only for an overall tooth shade matching.Our results support the natural backgrounds as valid alternatives to artificial ones. Using individual oral features as referral points, sustain personalized practices and provide a sustainable and easy clinical procedure.