Objective To observe the immediate sealing effect of pinus massoniana needle extract（PMNE） applied locally on dentin tubules and provide experimental basis for prevention and treatment of dentin hypersensitivity using PMNE. Method Dentin samples with open dentin tubule were prepared using 37% phosphoric acid gel. 60 samples were randomly divided into ethanol group

rosin-coated group

2% PMNE group

4% PMNE group

8% PMNE group and 8% PMNE-coated group using a random number table

with 10 samples in each group. The surface of samples was transient pre-coated 2 times using ethanol solution

rosin ethanol solution

2%PMNE ethanol solution

4% PMNE ethanol solution

8% PMNE ethanol solution and 8% PMNE film-coating agent in each group respectively. The surface morphologies of dentin in each group after pre-coating were observed using field emission scanning electron microscope（FESEM）

and the area of dentin tubular openings（ADTO） and the percentage area of dentin tubular openings（PADTO） in each group were also measured. The 10 remaining samples were divided into 2 groups

with 5 samples in each group

and the surface of samples was eluted by ethanol after transient pre-coated 2 times using rosin ethanol solution and 8% PMNE film-coating agent respectively. The morphologies of dentin surface were also observed using FESEM. Results The dentin tubules were sealed to different degrees in 2% PMNE group

4% PMNE group

8% PMNE group and 8% PMNE-coated group after the sealing treatment

and the degree of sealing of the tubules openings increased with the increase of PMNE concentration. The ADTO and PADTO of rosin-coated

4% PMNE

8% PMNE and 8% PMNE-coated group were significantly lower than that of the ethanol group

and the differences have statistically significant（P<0.05）.The ADTO and PADTO of 8% PMNE group were higher than those of the 8% PMNE-coated group

but which both had no significant difference with those of the rosin-coated group（P>0.05）.The morphology of dentin surface which pre-coated using 8% PMNE film-coating agent and eluted by ethanol was similar to that of dentin surface which pre-coated using 2% PMNE ethanol solution. Conclusions PMNE local transient pre-coating treatment could obtain good immediate sealing effect of dentin tubules

and the effect of 8% PMNE coating agent is better.