Aim: Todeterminetheadhesionstrength(measuredasshearbondstrength,SBS)oforthodontic

bracketsusingtwoexperimentalsilane-basedprimersystemsandcompareandcontrasttheireffect.

Materials andmethods: Sixty acid-etchedpremolarswererandomlyassignedinto4studygroups(n¼15).

In group1,bracketswerebondedwithoutprimerbutusingTransbondXTadhesive;ingroup2,Trans-

bond XTprimerwasappliedandbracketbonded;ingroup3,anexperimentalsilane-basedprimerof

1.0vol%of3-acryloxypropyltrimethoxysilane(ACPS)wasappliedbeforebonding;ingroup4,an

experimentalsilane-basedprimerof1.0vol%ofACPSþ0.5% bis-1,2-(triethoxysilyl)ethane(BTSE)was

used. Theadhesionstrength(measuredasshearbondstrength)wasrecordedusingauniversaltesting

machine. Failuretypeswereclassified accordingtotheAdhesiveRemnantIndex(ARI).Contactanglesof

the primersweremeasuredonanenamelslab.

Data wasanalyzedbyANOVAandTukey'smultiplecomparison post hoc analysis.

Results: The meanadhesionstrengthresultswerehighingroup4:15.871.6MPafollowedbygroup3:

12.571.5MPa,group2:11.971.1MPaandthelowestingroup1:08.170.7 MPa.Asignificant difference

in adhesionstrengthwasobservedbetweenallthegroupsexceptforgroup3andgroup4(po0.01).

The ARIscorewasdistributedlargelyto0and1.Oneinstanceofenamelfractureswasrecordedin

group 1.Thecontactanglemeasurementssuggestedthatthelowestvaluewiththeexperimentalprimer

containing (ACPSþBTSE) was, o5° followedbyTransbondXT,41.8674.56°.

Conclusion: The experimentalsilaneprimersystemswerehydrophilicinnatureanddemonstrated

higher adhesion strength compared to traditional orthodontic primers.