Effect of time on bond strength in indirect bonding.
The purpose of this in vitro investigation was to determine the influence of a reduced time interval before debonding on shear bond strength of stainless steel brackets bonded with a custom base indirect technique. A total of 135 bovine permanent mandibular incisors was randomly divided into nine groups of 15 specimens each. Three base composite-sealant combinations were investigated: (1) Phase II base composite, Custom I.Q. sealant, (2) Phase II base composite, Maximum Cure sealant, and (3) Transbond XT base composite, Sondhi Rapid Set sealant. Shear bond strength was measured for three different debonding time intervals: (1) time of transfer tray removal as recommended by the manufacturer, (2) 30 minutes after bonding of the sealant, and (3) 24 hours after bonding of the sealant. For groups bonded with Maximum Cure or Sondhi Rapid Set sealants, no influence of debonding time on shear bond strength was found. The Custom I.Q. sealant groups showed significantly lower bond strength measurements when debonded at the recommended tray removal time, and the Weibull analysis indicated a higher risk of bond failure at clinically relevant levels of stress. All base composite-sealant combinations showed acceptable bond strength at 30 minutes and 24 hours after bonding of the sealant.
Klocke
Arndt
A
Department of Orthodontics, College of Denistry, University of Hamburg, Germany. klocke@uke.uni-hamburg.de
Shi
Jianmin
J
Vaziri
Farhad
F
Kahl-Nieke
Bärbel
B
Bismayer
Ulrich
U
D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D003188:Composite Resins; D001840:Dental Bonding / Q000295:instrumentation* / Q000379:methods*; D017005:Dental Debonding; D003799:Dental Stress Analysis; D008422:Materials Testing; D016910:Orthodontic Brackets; D011897:Random Allocation; D019279:Resin Cements; D033081:Shear Strength; D013193:Stainless Steel; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors
D003188:Composite Resins; C090340:Reliance resin cement; D019279:Resin Cements; C477791:Sondhi Indirect Bonding Resin; C477790:Transbond XT; C487385:custom I.Q. sealant; C087211:maximum cure; D013193:Stainless Steel