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 comparespectrophotometric backgrounds - white (WB) withcuspal (C), black (BB) with non cuspal (NC) - in order todetermine if the oral natural conditions could be used as reliablebackgrounds instead of the traditional black and/or whitefor in vivo color matching.Methods: Spectrophotometric measurements were performedon ninety-three upper right permanent central incisor.Among inclusion criteria were A1, A2, A3 (Vita Classicalscale) tooth shade. Each tooth was measured on black, white,cuspal and non cuspal backgrounds. ΔE between black andnon cuspal (ΔEBBNC) and ΔE between white and cuspal(ΔEWBC) were calculated and correlated to human eye colorperception (AT, PT). Opalescence (O) and contrast ratio (CR)were calculated on the four different backgrounds.Results: The comparison between black and oral cavitynatural backgrounds shows high clinical acceptability:98.9% in the central, 96.8% in the gingival and 92.4% in theincisal tooth area. Clinical acceptability between white andoral cuspal backgrounds was 90.3% in the gingival, 79.6% inthe central and 7.6% in the incisal tooth area.CONCLUSIONS: Natural oral black background can alwaysbe used instead of the artificial one, while the natural brightoral background can be used instead of the artificial one onlyfor an overall tooth shade matching.Our results support thenatural backgrounds as valid alternatives to artificial ones.Using individual oral features as referral points, sustain personalizedpractices and provide a sustainable and easy clinicalprocedure.