Comparison of shear bond strength and bonding time of metal flash free orthodontic bracket

Abstract

Purpose: The purpose of this in vitro study is to compare the shear bond strength andbonding time between metal flash-free brackets and conventional metal brackets.Remaining adhesive following removal of orthodontic brackets was also assessed.Materials and Methods: Forty five intact human premolars (N =45, n = 15 per group)were selected and randomly divided into three groups. Group1: Smart clip brackets usedas control group, Group 2: Smart clip APC II flash-free adhesive coated brackets used asfirst experimental group, Group 3: Smart clip APC plus adhesive coated brackets used assecond experimental group. The bonding time was calculated after the teeth wereprepared until the brackets placed in the ideal position in seconds. Shear bond strength(SBS) for each sample was measured. Samples were then examined under X 8magnification light microscopy to assess the remaining adhesive. The shear bondstrength, bonding time and remaining adhesive of each group were statisticallycompared using t-test p<0.05.Results: The mean bonding time of smart clip group (40.1140) had significantlydifference when compared with APC II group (31.0560) (p=0.00), and did not showsignificant difference when compared with the smart clip APC plus (39.5431) group(p=0.638).The mean shear bond strength of smart clip group had significantly higher mean shearbond strength value (11.25120) when compared with APC II (9.42347) and APC plus(8.42867) group (p=0.00 , p=0.00 respectively).The mean residual adhesive of smart clip group (1.73) did not show significantdifference when compared with APC II group (1.93) (p=0.558). The mean ARI of smartclip group had significantly higher mean ARI value (1.73) when compared with APCplus (0.87) group (p=0.033).onclusions: APC flash-free adhesive coated bracket systems had shear bondstrength clinically acceptable. The APC flash free adhesive system is able todecrease the time needed for orthodontic bracket bonding. More adhesive remainingon the bracket appear to be favorable to save chair time during debonding butincrease the risk of enamel surface damage due to enamel fracture on bracketremoval.Key words: Flash free b

Purpose: The purpose of this in vitro study is to compare the shear bond strength andbonding time between metal flash-free brackets and conventional metal brackets.Remaining adhesive following removal of orthodontic brackets was also assessed.Materials and Methods: Forty five intact human premolars (N =45, n = 15 per group)were selected and randomly divided into three groups. Group1: Smart clip brackets usedas control group, Group 2: Smart clip APC II flash-free adhesive coated brackets used asfirst experimental group, Group 3: Smart clip APC plus adhesive coated brackets used assecond experimental group. The bonding time was calculated after the teeth wereprepared until the brackets placed in the ideal position in seconds. Shear bond strength(SBS) for each sample was measured. Samples were then examined under X 8magnification light microscopy to assess the remaining adhesive. The shear bondstrength, bonding time and remaining adhesive of each group were statisticallycompared using t-test p<0.05.Results: The mean bonding time of smart clip group (40.1140) had significantlydifference when compared with APC II group (31.0560) (p=0.00), and did not showsignificant difference when compared with the smart clip APC plus (39.5431) group(p=0.638).The mean shear bond strength of smart clip group had significantly higher mean shearbond strength value (11.25120) when compared with APC II (9.42347) and APC plus(8.42867) group (p=0.00 , p=0.00 respectively).The mean residual adhesive of smart clip group (1.73) did not show significantdifference when compared with APC II group (1.93) (p=0.558). The mean ARI of smartclip group had significantly higher mean ARI value (1.73) when compared with APCplus (0.87) group (p=0.033).Conclusions: APC flash-free adhesive coated bracket systems had shear bondstrength clinically acceptable. The APC flash free adhesive system is able todecrease the time needed for orthodontic bracket bonding. More adhesive remainingon the bracket appear to be favorable to save chair time during debonding butincrease the risk of enamel surface damage due to enamel fracture on bracketremoval.