Clinical Accuracy of an Intraoral Scanner for Tooth Shade Selection Compared With a Spectrophotometer and Visual Matching: A Comparative Study

OBJECTIVES: This study evaluated the performance of an intraoral scanner (Medit i700) for tooth shade selection by comparing it with a spectrophotometric reference device (VITA Easyshade) and visual observers, using VITA Classical and VITA 3D-Master shade guides. MATERIAL AND METHODS: Sixteen patients (48 right maxillary teeth: central incisor, canine, and first molar) were recruited from the fixed prosthodontics clinic. For each tooth, shade was recorded three times with Medit i700, three visual observers, and VITA Easyshade under standardized daylight conditions using both VITA Classical and VITA 3D-Master guides. Easyshade was used as the reference. Exact shade matching between each method and the reference was calculated as percentages. A secondary analysis focused on the value (brightness) component, assessing exact value match and value acceptability within ± 1 value level. Chi-square tests were applied to explore the influence of method, shade guide, and tooth type on value outcomes (α = 0.05). RESULTS: Exact shade matching was low for all methods and both shade guides. When only value was considered, agreement increased substantially: the intraoral scanner and visual observers achieved moderate exact value matches and high value acceptability (typically > 80% within ± 1 value level of the reference) across both shade guides. Chi-square analysis showed no significant differences in value performance between methods; however, shade guide type showed a significant effect on exact value matching, while value acceptability did not differ. In contrast, tooth type had a statistically significant influence on value outcomes, with higher agreement in molars (and, to a lesser extent, canines) than in incisors (p < 0.05). CONCLUSIONS: Within the limitations of this clinical study, the intraoral scanner Medit i700 did not provide sufficient accuracy for full shade selection, but showed high agreement for value determination. Intraoral scanners should be integrated with spectrophotometric and controlled visual assessment for shade matching in esthetic restorations.