Objective To investigate the reliability of electrochemical enzyme-linked immunosorbent assay(ELISA) for the detection of dentin sialophosphoprotein(DSPP) in gingival crevicular fluid(GCF) of orthodontic patients.Methods GCF were collected from the orthodontic patients,and then the amount of DSPP in GCF were detected by electrochemical ELISA and spectroscopic ELISA respectively.The difference between the results of two methods were analyzed.Results In electrochemical ELISA,the second order derivative linear sweep voltammetric peak current was linear with DSPP concentration in the range from 0.25-800.00 ng/L.It was found that the detection limit of the electrochemical method(0.25 ng/L) was much lower than that of the spectroscopic method.The paired-samples rank sum test showed no significant difference between the DSPP concentrations in human GCF samples measured by spectroscopic ELISA procedure and those measured by electrochemical ELISA procedure(P=0.063).Conclusions Electrochemical ELISA is a viable way of detecting DSPP in GCF with higher sensitivity than spectroscopic ELISA.