Abstract: Abstract： Objective To investigate the remineralizing therapy of deep caries and in vitro biomimetic remineralization of demineralized dentin by phosphorylated chitosan/amorphous calcium phosphate compound (P-chi/ACP) and tripolyphos⁃ phate (TPP). Methods Thirty-two extracted human molars were cut and completely demineralized. Two samples were used to show the characteristics by transmission electron microscopy (TEM). The other 30 samples were divided into two groups: fifteen samples were treated by P-chi/ACP and TPP (P-chi/ACP+TPP group), the other fifteen samples were not treated by TPP (P-chi/ACP group). All of the samples were distinguished into experimental side and control side, and then they were set on the in vitro model for 1 week. Micro-computed tomography (μCT) and TEM were used to assess the effects of reminer⁃ alization. Results μCT detection revealed that the mineral density were higher in the experimental sides (125.42±12.16 and 119.39±8.64) than that of control sides (96.96±10.56 and 105.27±9.42) in both groups (P < 0.01). TEM figures showed that hierarchical intrafibrillar remineralization was realized in samples of P-chi/ACP+TPP group, while trace amounts of hi⁃ erarchical remineralization was detected in P-chi/ACP group. Conclusion Fully demineralized dentin appears to have the potential to be remineralized with the application of P-chi/ACP. The ultrastructure of samples is better in P-chi/ACP+TPP group than that of P-chi/ACP group.

Key words: dentin, bionics, phosphorylated chitosan, sodium tripolyphosphate, remineralization