[The effects of different enamel etching time on bonding strength].

Objective: The aim of this study was to investigate the effect of short enamel etching time on bonding strength.
Methods: 80 healthy premolars were randomly divided into two equal groups, one was etched for 15 seconds, the other for 60 seconds, after normally bonding Edgewise brackets, the tooth specimen was stored in water at room temperature for 24 hours. An MTS NEW810 100KN testing machine was used to examine the shear force.
Results: Although the bonding strength for 15 seconds etching time was weaker than that for 60 seconds, the means of the bonding strength in 15 seconds group reached 5.8625 MPa.
Conclusion: Etching for 15 seconds could provide enough bond strength for orthodontic practice. Furthermore, the adhesive remained on tooth after debonding was less by comparison with 60 seconds etching group, therefore brackets could be removed easily and the work efficiency could be increased in clinic by means of 15 seconds etching time.