Dentin and Enamel Exposure on Upper Incisors for Bonding Buccal Laminated Veneers: Method Validation and Ex Vivo Quantification

Objectives This study compared the accuracy of postetching macrophotography, a clinically applicable method, with microscope observation (the laboratory reference) for quantifying enamel and dentin surfaces. A secondary objective was to assess the proportion of exposed dentin and enamel at different veneer preparation depths and to develop a classification system to optimize bonding protocols based on dentin exposure. Methods Twenty‐five human maxillary incisors underwent three sequential buccal reduction steps corresponding to ceramic laminate veneer (LV) preparation: minimally invasive preparation (MIP), semi‐invasive preparation (SIP), and invasive preparation (IP). After each preparation step, teeth were etched with 37% orthophosphoric acid for 15 s and subsequently evaluated using optical microscopy at 20× magnification and standardized postetching macrophotography. Enamel and dentin surfaces were quantified on both image sets using ImageJ software. Results During MIP, no dentin was exposed. After SIP, dentin exposure averaged 22% ± 20% for central incisors and 22% ± 15% for lateral incisors ( p = 0.93). After IP, dentin exposure increased to 84% ± 3% for central incisors and 69% ± 14% for lateral incisors ( p = 0.0002). No significant differences were found between the methods in measuring the proportions of dentin. Conclusions Postetching macrophotography provided dentin‐exposure measurements comparable to the reference optical microscopy method, supporting its use as a reliable and clinically applicable assessment tool. MIP and SIP preserved the majority of enamel in maxillary incisors, ensuring favorable bonding. A three‐stage classification system based on dentin exposure was developed to help practitioners adapt bonding protocols. Clinical significance This classification system, combined with a method for assessing residual enamel, offers a guide for customizing bonding protocols in veneer preparation.