human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: This study evaluated the shear bond strength of stainless steel brackets bonded to enamel with a new fluoride-releasing orthodontic adhesive system . A total of 140 extracted human bicuspids were r and omly divided into four groups . Group I ( Transbond XT ) was a control group in which enamel was etched with phosphoric acid . For the remaining groups , enamel was conditioned with a self-etching primer ( SEP ) : Group II ( Transbond Plus ) , Group III ( BeautyOrtho Bond ) , and Group IV ( BeautyOrtho Bond + Salivatect ) . Stainless steel brackets were bonded to all tooth sample s. After which , the sample s were stored , thermocycled , tested , and statistically analyzed . Besides bond strength evaluation , the adhesive remnant index ( ARI ) was also evaluated . The shear bond strengths of Groups II , III , and IV were significantly lower than Group I , and Group II was significantly greater than that of Group III . Concerning ARI scores , no significant differences were found between the groups . Further , no enamel fracture was observed during shear bond test with the new SEP . In conclusion , when enamel was conditioned with the new SEP , the mean values of shear bond strength yielded were lower than when it was etched with 37 % phosphoric acid . Nonetheless , these mean values were higher than the average suggested by Reynolds as optimum for clinical treatment The purpose of this study was to determine the effect of changing the crosshead speed of the testing machine on the shear bond strength of orthodontic brackets to enamel while st and ardizing all the other variables . Forty freshly extracted human molars were bonded using the Transbond XT adhesive system ( 3 M Unitek , Monrovia , Calif ) . The teeth were r and omly divided into two groups . In group I , the shear bond strength was measured at a crosshead speed of 5.0 mm/min , and in group II the shear bond strength was measured at a crosshead speed of 0.5 mm/ min . Within half an hour from the initial bonding of each tooth , an occlusogingival load was applied to the bracket , producing a shear force at the bracket-tooth interface . This was accomplished by using the flattened end of a steel rod attached to the crosshead of a Universal Test Machine ( Zwick GmbH & Co , Ulm , Germany ) . The t-test results ( t = 2.71 ) indicated that there was a significant difference ( P = .014 ) in the shear bond strengths between the group tested at a crosshead speed of 5.0 mm/min and the group tested at a crosshead speed of 0.5 mm/min . The mean shear bond strengths for the two groups were 7.0 + /- 4.6 MPa and 12.2 + /- 4.0 MPa , respectively . These findings indicated that it is important to identify the parameters included in shear bond testing in order to enable meaningful comparisons of the performance of different material The purpose of our study was to determine the effect of a 35 % hydrogen peroxide bleaching agent on the shear bond strength of metallic orthodontic brackets . Sixty premolars were r and omly divided into 3 groups of 20 each . Teeth in group A were etched with 37 % phosphoric acid before bonding metallic premolar brackets . Teeth in the other 2 groups were bleached with a 35 % hydrogen peroxide in-office bleaching agent according to the manufacturer 's recommendations . Twenty bleached teeth ( group B ) were bonded immediately , and the other 20 ( group C ) were stored in artificial saliva for 30 days before bonding . Shear bond strength of these brackets was measured on a universal testing machine and recorded in MPa . Adhesive remnant index ( ARI ) scores were determined after the brackets failed . Data were analyzed with analysis of variance ( ANOVA ) and chi-square tests . The shear bond strength values of groups A , B , and C were 12.9 + /- 3.4 , 12.0 + /- 4.6 , and 14.8 + /- 4.0 MPa , respectively . Results of ANOVA showed no statistically significant differences in shear bond strengths between groups ( P > .05 ) . ARI scores were significantly different in all groups . The unbleached group 's failures were primarily at the bracket/adhesive interface , whereas the bleached groups either showed cohesive failures within the adhesive or failed at the adhesive/enamel interface . The results of this study suggest that office bleaching with hydrogen peroxide does not adversely affect the bond strengths of brackets bonded immediately after bleaching or 30 days after bleaching , even though bleaching can result in differences in the failure site The objective of this in vitro bonding study was to evaluate the effectiveness of 2 moisture-insensitive primers , Assure ( Reliance Orthodontic Products , Itasca , Ill ) and MIP ( 3 M Unitek , Monrovia , Calif ) compared with a control hydrophobic primer , Transbond XT ( 3 M Unitek ) . Six groups of 40 premolars were acid etched and bonded using metal orthodontic brackets with the following in vitro protocol s : ( 1 ) Transbond XT primer and adhesive applied to a noncontaminated surface ; ( 2 ) Assure primer applied after saliva contamination ; ( 3 ) MIP primer applied after saliva contamination ; ( 4 ) Assure primer reapplied after saliva contamination ; ( 5 ) MIP reapplied after saliva contamination ; and ( 6 ) Assure adhesive applied after saliva contamination of the primer . All bonded specimens were stored in deionized water at 37 degrees C for 30 days and thermocycled for 24 hours before debonding . Brackets were debonded using a shear-peel load on a testing machine , bond strength was measured in megapascals , and bond failure was analyzed by using the adhesive remnant index . In vitro shear-peel bond strengths were acceptable for all groups , and the bond strengths for Assure and MIP were not significantly affected by saliva contamination . The mean shear-peel bond strength of the control ( 14.82 MPa ) was significantly higher ( P < .001 ) than the contaminated groups with the exception of MIP group 5 ( 14.02 MPa ) . The values of the Assure primer and adhesive were less than the MIP primer and its respective adhesive ; however , the hydrophilic Assure adhesive resin applied to a saliva-contaminated surface had acceptable bond strength . Bond failure analysis ( adhesive remnant index ) mainly showed adhesive bond failures . An increased frequency of enamel fractures at debond was noted , with the control group ( 1 ) and the MIP groups ( 3 and 5 ) having 22.5 % , 12.5 % , and 15 % , respectively . The Assure groups had no enamel fractures It has been cl aim ed that different ion solutions containing sulfate induce crystal growth and might be a better alternative than conventional acid etching for enamel pretreatment in bracket bonding . It should thus combine optimal bond strength with easy and quick debonding . Two clinical experiments were performed to test this hypothesis . The first experiment dealt with the debonding procedure . Following conditioning with dilute sulfuric acid which contained sodium sulfate ( to be termed solution A ) on one side of the mouth and etching with 37 % phosphoric acid on the other , brackets were bonded on the maxillary and m and ibular incisors of twenty dental nurse students . Debracketing and a subsequent cleanup procedure were performed after 2 days . The mode of loosening was mainly between the enamel surface and adhesive on the crystal-growth-conditioned teeth and between the bracket mesh and adhesive on the teeth etched with phosphoric acid . This difference in mode of loosening was statistically significant ( P less than 0.001 ) . In the second experiment , which dealt with the clinical bond strength , 250 brackets were bonded in forty patients . One side served as a control and was conventionally acid etched . On the experimental side conditioning was done with solution A in thirty patients . In ten patients , 10 % phosphoric acid was added to the dilute sulfuric acid used ( to be termed solution B ) . Failure rates and modes of failure were recorded for a 6-month period . ( ABSTRACT TRUNCATED AT 250 WORDS Currently introduced self-etching primers combine conditioning and priming agents into a single product . The purpose of this study was to determine the effects of using three self-etching primers on the shear bond strength ( SBS ) of orthodontic brackets and on the bracket/adhesive failure mode . Brackets were bonded to extracted human teeth according to one of four protocol s. In the control group , teeth were etched with 37 % phosphoric acid . In the experimental groups , the enamel was conditioned with three different self-etching primers , Clearfil SE Bond ( CSE ) , Etch & Prime 3.0 ( EP3 ) , or Transbond Plus ( TBP ) , as suggested by the manufacturer . The brackets were then bonded with Transbond XT in all groups . The present in vitro findings indicate that conditioning with TBP before bonding orthodontic brackets to the enamel surface result ed in a significantly ( P < or = .001 ) higher SBS ( mean , 16.0 + /- 4.5 MPa ) than that found in CSE , EP3 , and the control ( acid-etched [ AE ] ) groups . CSE produced bond strength values ( mean 11.5 + /- 3.3 MPa ) that are statistically comparable to those produced by acid etching ( mean 13.1 + /- 3.1 MPa ) . The use of EP3 for enamel conditioning result ed in the lowest mean SBS value ( mean 9.9 + /- 4.0 MPa ) . A comparison of the adhesive remnant index scores indicated that there was more residual adhesive remaining on the teeth that were treated with conventional acid etching than in the CSE and EP3 groups . In the TBP group , the failure sites were similar to those of the AE group but different from those of the CSE group Many bracket base design s and adhesive material s are in clinical use today . Bases have evolved from perforated metal bases to the present foil mesh bases , and treatments range from none , to spraying metal alloy onto the base , to the most common treatment of microetching . The purpose of this study was to determine the effect of orthodontic bracket base design on mean shear bond strength 1 hour or 24 hours after bonding . For each time group , 12 specimens of 6 types of metal brackets were bonded to bovine incisors with Transbond XT ( 3 M Unitek , Monrovia , Calif ) light-cured composite resin . Brackets were debonded 1 hour or 24 hours later , and the shear bond strength was recorded . Six debonded brackets of each type from each time group were selected at r and om and s and blasted . All the teeth were cleaned , and half were rebonded with used brackets , and half were rebonded with new brackets . Bond strength was measured again , 1 hour or 24 hours later . Representative specimens were inspected under the scanning electron microscope . Bracket base design significantly affected mean shear bond strength . Speed ( 60-gauge , microetched foil-mesh base ; Strite Industries , Cambridge , Ontario , Canada ) had the highest bond strength at 1 hour ; followed by Time ( machined , integral , microetched base with mechanical undercuts ; American Orthodontics , Sheboygan , Wis ) ; American Master Series ( 80-gauge foil-mesh base ; American Orthodontics ) ; Ovation Roth ( 80-gauge layered onto 150-gauge , microetched foil-mesh base ; GAC , Central Islip , NY ) ; Orthos Optimesh XRT ( 100-gauge microetched foil-mesh base ; Ormco , Orange , Calif ) ; and , finally , the nickel-free brackets ( injection molded , 100-gauge , microetched , foil-mesh base ; World Class Technology , McMinnville , Ore ) . The 24-hour results were similar except that Time had the highest mean shear bond strength ( ANOVA , P < .05 ) . Chairside s and blasting significantly affected the 1-hour , but not the 24-hour , mean shear bond strengths ( ANOVA , P < .05 ) . S and blasting appears to be an effective method of cleaning bracket bases before rebonding INTRODUCTION This study assessed in-vitro shear bond strength and in-vivo survival rate of orthodontic brackets bonded with either a halogen  or a plasma arc light . METHODS Ninety extracted premolars were divided into 6 groups of 15 . Stainless steel brackets were bonded to the teeth by using either a halogen light with a 20-second curing time or a plasma arc light with a 2- , 6- , or 10-second curing time . Brackets were debonded either within 30 minutes of bonding or after thermocycling for 24 hours . Bond strengths were tested on a testing machine at a crosshead speed of 1 mm/minute . The bracket failure interface was measured with a modified adhesive remnant index score . Data were analyzed by using ANOVA and Tukey-Kramer multiple comparison tests . For the in-vivo study , a split-arch design was used to determine the bracket-failure rate and distribution in 25 patients . The patients were followed for a mean period of 1.1 years ( 386 days ) . Survival analysis was carried out to compare the failure rates of the 2 techniques . RESULTS No significant differences in bond strengths were found 30 minutes after bonding between the halogen light ( 13.6 + /- 3.8 MPa ) and the plasma arc light with 2- , 6- , or 10-second curing times ( 9.6 + /- 2.9 , 14.2 + /- 4.6 , 16.0 + /- 3.0 MPa , 
    Output:
    
agent
Many studies on in-vitro orthodontic bond strength fail to report test conditions that could significantly affect their outcomes
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: This study evaluated the shear bond strength of stainless steel brackets bonded to enamel with a new fluoride-releasing orthodontic adhesive system . A total of 140 extracted human bicuspids were r and omly divided into four groups . Group I ( Transbond XT ) was a control group in which enamel was etched with phosphoric acid . For the remaining groups , enamel was conditioned with a self-etching primer ( SEP ) : Group II ( Transbond Plus ) , Group III ( BeautyOrtho Bond ) , and Group IV ( BeautyOrtho Bond + Salivatect ) . Stainless steel brackets were bonded to all tooth sample s. After which , the sample s were stored , thermocycled , tested , and statistically analyzed . Besides bond strength evaluation , the adhesive remnant index ( ARI ) was also evaluated . The shear bond strengths of Groups II , III , and IV were significantly lower than Group I , and Group II was significantly greater than that of Group III . Concerning ARI scores , no significant differences were found between the groups . Further , no enamel fracture was observed during shear bond test with the new SEP . In conclusion , when enamel was conditioned with the new SEP , the mean values of shear bond strength yielded were lower than when it was etched with 37 % phosphoric acid . Nonetheless , these mean values were higher than the average suggested by Reynolds as optimum for clinical treatment The purpose of this study was to determine the effect of changing the crosshead speed of the testing machine on the shear bond strength of orthodontic brackets to enamel while st and ardizing all the other variables . Forty freshly extracted human molars were bonded using the Transbond XT adhesive system ( 3 M Unitek , Monrovia , Calif ) . The teeth were r and omly divided into two groups . In group I , the shear bond strength was measured at a crosshead speed of 5.0 mm/min , and in group II the shear bond strength was measured at a crosshead speed of 0.5 mm/ min . Within half an hour from the initial bonding of each tooth , an occlusogingival load was applied to the bracket , producing a shear force at the bracket-tooth interface . This was accomplished by using the flattened end of a steel rod attached to the crosshead of a Universal Test Machine ( Zwick GmbH & Co , Ulm , Germany ) . The t-test results ( t = 2.71 ) indicated that there was a significant difference ( P = .014 ) in the shear bond strengths between the group tested at a crosshead speed of 5.0 mm/min and the group tested at a crosshead speed of 0.5 mm/min . The mean shear bond strengths for the two groups were 7.0 + /- 4.6 MPa and 12.2 + /- 4.0 MPa , respectively . These findings indicated that it is important to identify the parameters included in shear bond testing in order to enable meaningful comparisons of the performance of different material The purpose of our study was to determine the effect of a 35 % hydrogen peroxide bleaching agent on the shear bond strength of metallic orthodontic brackets . Sixty premolars were r and omly divided into 3 groups of 20 each . Teeth in group A were etched with 37 % phosphoric acid before bonding metallic premolar brackets . Teeth in the other 2 groups were bleached with a 35 % hydrogen peroxide in-office bleaching agent according to the manufacturer 's recommendations . Twenty bleached teeth ( group B ) were bonded immediately , and the other 20 ( group C ) were stored in artificial saliva for 30 days before bonding . Shear bond strength of these brackets was measured on a universal testing machine and recorded in MPa . Adhesive remnant index ( ARI ) scores were determined after the brackets failed . Data were analyzed with analysis of variance ( ANOVA ) and chi-square tests . The shear bond strength values of groups A , B , and C were 12.9 + /- 3.4 , 12.0 + /- 4.6 , and 14.8 + /- 4.0 MPa , respectively . Results of ANOVA showed no statistically significant differences in shear bond strengths between groups ( P > .05 ) . ARI scores were significantly different in all groups . The unbleached group 's failures were primarily at the bracket/adhesive interface , whereas the bleached groups either showed cohesive failures within the adhesive or failed at the adhesive/enamel interface . The results of this study suggest that office bleaching with hydrogen peroxide does not adversely affect the bond strengths of brackets bonded immediately after bleaching or 30 days after bleaching , even though bleaching can result in differences in the failure site The objective of this in vitro bonding study was to evaluate the effectiveness of 2 moisture-insensitive primers , Assure ( Reliance Orthodontic Products , Itasca , Ill ) and MIP ( 3 M Unitek , Monrovia , Calif ) compared with a control hydrophobic primer , Transbond XT ( 3 M Unitek ) . Six groups of 40 premolars were acid etched and bonded using metal orthodontic brackets with the following in vitro protocol s : ( 1 ) Transbond XT primer and adhesive applied to a noncontaminated surface ; ( 2 ) Assure primer applied after saliva contamination ; ( 3 ) MIP primer applied after saliva contamination ; ( 4 ) Assure primer reapplied after saliva contamination ; ( 5 ) MIP reapplied after saliva contamination ; and ( 6 ) Assure adhesive applied after saliva contamination of the primer . All bonded specimens were stored in deionized water at 37 degrees C for 30 days and thermocycled for 24 hours before debonding . Brackets were debonded using a shear-peel load on a testing machine , bond strength was measured in megapascals , and bond failure was analyzed by using the adhesive remnant index . In vitro shear-peel bond strengths were acceptable for all groups , and the bond strengths for Assure and MIP were not significantly affected by saliva contamination . The mean shear-peel bond strength of the control ( 14.82 MPa ) was significantly higher ( P < .001 ) than the contaminated groups with the exception of MIP group 5 ( 14.02 MPa ) . The values of the Assure primer and adhesive were less than the MIP primer and its respective adhesive ; however , the hydrophilic Assure adhesive resin applied to a saliva-contaminated surface had acceptable bond strength . Bond failure analysis ( adhesive remnant index ) mainly showed adhesive bond failures . An increased frequency of enamel fractures at debond was noted , with the control group ( 1 ) and the MIP groups ( 3 and 5 ) having 22.5 % , 12.5 % , and 15 % , respectively . The Assure groups had no enamel fractures It has been cl aim ed that different ion solutions containing sulfate induce crystal growth and might be a better alternative than conventional acid etching for enamel pretreatment in bracket bonding . It should thus combine optimal bond strength with easy and quick debonding . Two clinical experiments were performed to test this hypothesis . The first experiment dealt with the debonding procedure . Following conditioning with dilute sulfuric acid which contained sodium sulfate ( to be termed solution A ) on one side of the mouth and etching with 37 % phosphoric acid on the other , brackets were bonded on the maxillary and m and ibular incisors of twenty dental nurse students . Debracketing and a subsequent cleanup procedure were performed after 2 days . The mode of loosening was mainly between the enamel surface and adhesive on the crystal-growth-conditioned teeth and between the bracket mesh and adhesive on the teeth etched with phosphoric acid . This difference in mode of loosening was statistically significant ( P less than 0.001 ) . In the second experiment , which dealt with the clinical bond strength , 250 brackets were bonded in forty patients . One side served as a control and was conventionally acid etched . On the experimental side conditioning was done with solution A in thirty patients . In ten patients , 10 % phosphoric acid was added to the dilute sulfuric acid used ( to be termed solution B ) . Failure rates and modes of failure were recorded for a 6-month period . ( ABSTRACT TRUNCATED AT 250 WORDS Currently introduced self-etching primers combine conditioning and priming agents into a single product . The purpose of this study was to determine the effects of using three self-etching primers on the shear bond strength ( SBS ) of orthodontic brackets and on the bracket/adhesive failure mode . Brackets were bonded to extracted human teeth according to one of four protocol s. In the control group , teeth were etched with 37 % phosphoric acid . In the experimental groups , the enamel was conditioned with three different self-etching primers , Clearfil SE Bond ( CSE ) , Etch & Prime 3.0 ( EP3 ) , or Transbond Plus ( TBP ) , as suggested by the manufacturer . The brackets were then bonded with Transbond XT in all groups . The present in vitro findings indicate that conditioning with TBP before bonding orthodontic brackets to the enamel surface result ed in a significantly ( P < or = .001 ) higher SBS ( mean , 16.0 + /- 4.5 MPa ) than that found in CSE , EP3 , and the control ( acid-etched [ AE ] ) groups . CSE produced bond strength values ( mean 11.5 + /- 3.3 MPa ) that are statistically comparable to those produced by acid etching ( mean 13.1 + /- 3.1 MPa ) . The use of EP3 for enamel conditioning result ed in the lowest mean SBS value ( mean 9.9 + /- 4.0 MPa ) . A comparison of the adhesive remnant index scores indicated that there was more residual adhesive remaining on the teeth that were treated with conventional acid etching than in the CSE and EP3 groups . In the TBP group , the failure sites were similar to those of the AE group but different from those of the CSE group Many bracket base design s and adhesive material s are in clinical use today . Bases have evolved from perforated metal bases to the present foil mesh bases , and treatments range from none , to spraying metal alloy onto the base , to the most common treatment of microetching . The purpose of this study was to determine the effect of orthodontic bracket base design on mean shear bond strength 1 hour or 24 hours after bonding . For each time group , 12 specimens of 6 types of metal brackets were bonded to bovine incisors with Transbond XT ( 3 M Unitek , Monrovia , Calif ) light-cured composite resin . Brackets were debonded 1 hour or 24 hours later , and the shear bond strength was recorded . Six debonded brackets of each type from each time group were selected at r and om and s and blasted . All the teeth were cleaned , and half were rebonded with used brackets , and half were rebonded with new brackets . Bond strength was measured again , 1 hour or 24 hours later . Representative specimens were inspected under the scanning electron microscope . Bracket base design significantly affected mean shear bond strength . Speed ( 60-gauge , microetched foil-mesh base ; Strite Industries , Cambridge , Ontario , Canada ) had the highest bond strength at 1 hour ; followed by Time ( machined , integral , microetched base with mechanical undercuts ; American Orthodontics , Sheboygan , Wis ) ; American Master Series ( 80-gauge foil-mesh base ; American Orthodontics ) ; Ovation Roth ( 80-gauge layered onto 150-gauge , microetched foil-mesh base ; GAC , Central Islip , NY ) ; Orthos Optimesh XRT ( 100-gauge microetched foil-mesh base ; Ormco , Orange , Calif ) ; and , finally , the nickel-free brackets ( injection molded , 100-gauge , microetched , foil-mesh base ; World Class Technology , McMinnville , Ore ) . The 24-hour results were similar except that Time had the highest mean shear bond strength ( ANOVA , P < .05 ) . Chairside s and blasting significantly affected the 1-hour , but not the 24-hour , mean shear bond strengths ( ANOVA , P < .05 ) . S and blasting appears to be an effective method of cleaning bracket bases before rebonding INTRODUCTION This study assessed in-vitro shear bond strength and in-vivo survival rate of orthodontic brackets bonded with either a halogen  or a plasma arc light . METHODS Ninety extracted premolars were divided into 6 groups of 15 . Stainless steel brackets were bonded to the teeth by using either a halogen light with a 20-second curing time or a plasma arc light with a 2- , 6- , or 10-second curing time . Brackets were debonded either within 30 minutes of bonding or after thermocycling for 24 hours . Bond strengths were tested on a testing machine at a crosshead speed of 1 mm/minute . The bracket failure interface was measured with a modified adhesive remnant index score . Data were analyzed by using ANOVA and Tukey-Kramer multiple comparison tests . For the in-vivo study , a split-arch design was used to determine the bracket-failure rate and distribution in 25 patients . The patients were followed for a mean period of 1.1 years ( 386 days ) . Survival analysis was carried out to compare the failure rates of the 2 techniques . RESULTS No significant differences in bond strengths were found 30 minutes after bonding between the halogen light ( 13.6 + /- 3.8 MPa ) and the plasma arc light with 2- , 6- , or 10-second curing times ( 9.6 + /- 2.9 , 14.2 + /- 4.6 , 16.0 + /- 3.0 MPa , 
    Output:
    