The Use of Raman Spectroscopy in the Assessment of the Infiltration Depth of Experimental and Commercial Resin Materials in Extracted Teeth

Early enamel lesions result from pH imbalance in the oral cavity, causing subsurface de-mineralization. Resin infiltration has emerged as a minimally invasive treatment option that can halt lesion progression, filling and stabilizing enamel while improving esthetics and microhardness. Raman spectroscopy provides rapid, non-destructive analysis of enamel by detecting molecular vibrations that reflect its chemical composition and structural changes. It allows efficient characterization and depth profiling of dental tissues and materials. Raman spectra also enable quantitative assessment of compositional and structural alterations within enamel. This study aimed to assess the penetration depth of two experimental infiltration materials and a commercial resin within incipient demineralization enamel lesions using Raman spectroscopy. Artificial enamel lesions were created on three extracted human teeth. The samples were treated with a commercial resin infiltrate and two experimental resin infiltrates, with a modified recipe, following the manufacturer's protocol. Each tooth was sectioned into a 1 mm thick disk. Raman spectra were recorded at sequential depths across both the control (untreated) and infiltrated surfaces of each disk. Characteristic peaks corresponding to infiltrate's organic matrix and enamel's phosphate and carbonate groups were employed for assessing penetration depth.