Comparison of the retentive force for test samples at each time point (Figs. 
PK, NP, and BT showed significantly higher retentive force than the control immediately after application (p < 0.05). No significant difference was observed between DW and the control (p < 0.05). After 10 min of application, PK showed higher retentive force than the control (p < 0.05). NP showed the highest retentive force among the control and test substances (p < 0.05). BT and DW were comparable to the control (p < 0.05). After 20 min of application, PK showed higher retention than the control (p < 0.05). Similar with the 10-min duration, NP showed the highest retentive force among the control and test substances (p < 0.05). BT and DW were also comparable to the control (p < 0.05). After 30 min of application, only NP showed a higher retentive force than the control, PK, and BT. DW showed the highest retentive force among the test substances (p < 0.05). BT and DW were comparable to the control (p < 0.05).
Measuring retentive force (N)