Quantitive evaluation of dentin sialoprotein (DSP) using microbeads - a potential early marker of root resorption.

PURPOSE: This study had the aim of comparing two different methods of analysing dentin sialoprotein (DSP) in the gingival crevicular fluid (GCF): the conventional eLISA approach and a new method involving the use of magnetic micro-beads coated with an antibody specific for DSP prior to eLISA analysis.

MATERIALS AND METHODS: GCF was taken from six patients following twelve weeks of orthodontic treatment using paper strips inserted into the mesial and distal sulci of the upper incisors, and analysed using both methods.

RESULTS: Statistical analysis of the results using the Mann-Whitney non-parametric test showed that the micro-bead approach conferred more reliability and less variability on the conventional eLISA approach. Furthermore, this method, for the first time, enables the quantification of the DSP in the sample in ng/μl.

CONCLUSIONS: The innovative micro-bead/eLISA approach proposed provides a reliable means of quantifying the DSP in the GCF.