The dentin–enamel junction (DEJ) is the border where two different mineralized structures – enamel and dentin – meet. The protein‐rich DEJ, together with the inner enamel region of mature teeth, is known to exhibit higher fracture toughness and crack growth resistance than bulk phase enamel. However, an explanation for this behavior has been hampered by the lack of compositional information for the DEJ and the adjacent enamel organic matrix (EOM). We studied proteomes of the DEJ and EOM of healthy human molars and compared them with dentin and enamel proteomes from the same teeth. These tissues were cut out of tooth sections by laser capture microdissection, proteins were extracted and cleaved by trypsin, then processed by liquid chromatography coupled to tandem mass spectrometry to analyze the proteome profiles of these tissues. This study identified 46 proteins in DEJ and EOM. The proteins identified have a variety of functions, including calcium ion‐binding, formation of extracellular matrix, formation of cytoskeleton, cytoskeletal protein binding, cell adhesion, and transport. Collagens were identified as the most dominant proteins. Tissue‐specific proteins, such as ameloblastin and amelogenin, were also detected. Our findings reveal new insight into proteomics of DEJ and EOM, highly mineralized tissues that are obviously difficult to analyze.
A method of highly sensitive bismuth determination by hydride generation coupled with in-house assembled non-dispersive atomic fluorescence spectrometry was developed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.