Insights into the structure and composition of the peritubular dentin organic matrix and the lamina limitans

► We analyzed the microstructure and composition of the peritubular dentin organic matrix. ► We found a membrane named lamina limitans covering the dentin tubule walls after demineralization. ► Protruding from the lamina limitans we found noncollagenous filaments forming a complex network. ► Digestion with C-ABC suggested the filaments are primarily composed of glycosaminoglycans. ► Trypsin treatment suggested that lamina limitans is mainly composed of proteoglycan protein cores.