Medium-Specific Elemental and Ionic Screening of Archived Denture-Base Immersion Extracts: Matrix Effects, Blank Provenance, and Reporting Requirements

Background/Objectives. Chemical assessment of dental biomaterials in food and beverage media is complicated by endogenous matrix constituents and matrix-dependent analytical recovery, so post-immersion concentrations cannot be assigned to material-derived release without commutable blanks and a traceable normalisation chain. Methods. We re-analysed an archived denture-base dataset of 45 nominal result rows from three coded specimen groups after 30-day static exposure to water, red wine, coffee, diluted ketchup or orange juice. A 16-field panel of ICP-OES elements, ion-selective-electrode fields and sulfate and phosphate equivalents was retained. Fourteen fields entered exact within-medium permutation tests with Benjamini–Hochberg adjustment across 70 tests, while cadmium and chromium remained descriptive owing to mixed censoring. Results. In this exploratory analysis, fourteen comparisons met q < 0.05 and 56 did not, with thirteen of the fourteen qualifying combinations occurring in wine, coffee, ketchup or orange juice rather than water. Separately analysed media therefore produced different sets of coded-group-associated differences in unblanked extract composition, carried by trace elements and recorded anion fields rather than the bulk-ion background. Conclusions. The archive cannot establish absolute net release, exposure, material ranking or biocompatibility. Interpretable biomaterial extraction studies require independently identified specimens, replicated matrix-matched blanks, matrix-specific quality controls and a traceable conversion to mass- or area-normalised endpoints.