Shear bond strength of precoated orthodontic brackets: an in vivo study Comparison of bond strength between a conventional resin adhesive and a resin-modified glass ionomer adhesive: an in vitro and in vivo study. Effect of a self-etching primer on shear bond strength of adhesive precoated brackets in vivo. Shear bond strength comparison between two orthodontic adhesives and self-ligating and conventional brackets. Comparison of bracket debonding force between two conventional resin adhesives and a resin-reinforced glass ionomer cement: an in vitro and in vivo study. Clinical performance of orthodontic brackets and adhesive systems: a randomized clinical trial. Effect of self-etching primers on bond strength--are they reliable? A new self-curing resin-modified glass-ionomer cement for the direct bonding of orthodontic brackets in vivo. New protective polish effects on shear bond strength of brackets. Clinical comparison of direct versus indirect bonding with different bracket types and adhesives. Shear bond strength of a new fluoride-releasing orthodontic adhesive. Comparison of bond strength of three adhesives: composite resin, hybrid GIC, and glass-filled GIC. Argon laser vs conventional visible light-cured orthodontic bracket bonding: an in-vivo and in-vitro study. Microleakage under orthodontic brackets bonded with different adhesive systems How and why of orthodontic bond failures: An in vivo study Evaluation of enamel damages following orthodontic bracket debonding in fluorosed teeth bonded with adhesion promoter Comparison of bond strength between orthodontic brackets bonded with halogen and plasma arc curing lights: an in-vitro and in-vivo study. Clinical bond failure rates of adhesive precoated self-ligating brackets using a self-etching primer. The use of Ormocer as an alternative material for bonding orthodontic brackets. The influence of adding modified zirconium oxide-titanium dioxide nano-particles on mechanical properties of orthodontic adhesive: an in vitro study Clinical comparison between a resin-reinforced self-cured glass ionomer cement and a composite resin for direct bonding of orthodontic brackets. Part 2: Bonding on dry enamel and on enamel soaked with saliva. Effect of changing a test parameter on the shear bond strength of orthodontic brackets. An in vivo investigation into the use of resin-modified glass poly(alkenote) cements as orthodontic bonding agents.
Objective To evaluate the shear bond strength of precoated orthodontic brackets bonded with self-etching primer relative to that of noncoated conventionally-bonded brackets at two different time intervals . Methods Twenty-one subjects were selected for r and omized split-mouth bonding of two types of brackets to the maxillary arch . Half of the teeth had precoated brackets bonded using self-etching adhesive , and the other half had regular brackets bonded using Transbond XT adhesive . Nitinol wires were tied to the upper arch and were left until the time of debonding . The patients were r and omly divided into two groups : one debonded after one hour and the other debonded two weeks after the initial wire placement . The shear bond strength was directly recorded from the patients ’ mouths using an in vivo debonding device . Results There were no significant differences in shear bond strength between the precoated and conventional groups or within each group at different time intervals . There were significant differences between anterior and posterior teeth in both the precoated and conventional groups . Conclusion Pre-coated brackets bonded with self-etching adhesive have the same bonding strength as the conventionally bonded brackets The objectives of this study were ( 1 ) to compare the in vivo survival rates of orthodontic brackets bonded with a resin-modified glass ionomer adhesive ( Fuji Ortho LC ; GC America , Alsip , Ill ) after conditioning with 10 % polyacrylic acid and a conventional resin adhesive ( Light Bond ; Reliance Orthodontic Products , Itasca , Ill ) bonded with 37 % phosphoric acid , ( 2 ) to compare the in vitro bond shear/peel bond strength between the 2 adhesives , ( 3 ) to determine the mode of bracket failure in the in vivo and in vitro tests according to the adhesive remnant index ( ARI ) , and ( 4 ) to compare the changes in surface morphology of enamel surface after etching or conditioning with 10 % polyacrylic acid , with scanning electron microscopy . In the in vitro study , 50 extracted premolars were r and omly divided into 4 groups : brackets bonded with Fuji Ortho LC or Light Bond adhesive that were debonded after either 30 minutes or 24 hours . Bond strengths were determined with a testing machine at a crosshead speed of 1 mm/min . Data were analyzed with analysis of variance and a paired Student t test . The in vivo study consisted of 398 teeth that were r and omly bonded with Fuji Ortho LC or Light Bond adhesive in 22 subjects with the split-mouth technique . Bracket survival rates and distribution were followed for 1.3 years . Data were analyzed with Kaplan-Meier product-limit estimates of survivorship function . The in vitro study results showed significant differences ( P < .05 ) among the adhesives and the debond times . Light Bond had significantly greater bond strengths than Fuji Ortho LC at 24 hours ( 18.46 + /- 2.95 MPa vs 9.56 + /- 1.85 MPa ) and 30 minutes ( 16.19 + /- 2.04 MPa vs 6.93 + /- 1.93 MPa ) . Mean ARI scores showed that Fuji Ortho LC had significantly greater incidences of enamel/adhesive failure than Light Bond adhesive ( 4.9 vs 4.1 ) . For the in vivo study , no significant differences in failure rate , sex , or location in dental arch or ARI ratings were found between the 2 adhesives . These results suggest that , compared with conventional resin , brackets bonded with resin-modified glass ionomer adhesive had significantly less shear bond strength in vitro . However , similar survival rates of the 2 material s studied after 1.3 years indicate that resin-reinforced glass ionomers can provide adequate bond strengths clinical ly . The weaker chemical bonding between the adhesive and the enamel might make it easier for clinicians to clean up adhesives on the enamel surface after debonding The aim of this study was to evaluate the influence of a self-etching primer ( SEP ) ( Transbond Plus SEP , 3 M Unitek , Monrovia , Calif ) on shear bond strength of adhesive uncoated and precoated Victory brackets ( 3 M Unitek ) . The sample group consisted of 23 patients , with four premolars each , equally divided in four different groups . Brackets were bonded in vivo by the same operator using a split-mouth r and om technique : group 1 , 37 % phosphoric acid + primer + composite + conventional Victory bracket ; group 2 , 37 % phosphoric acid + primer + precoated Victory bracket ; group 3 , SEP + composite + conventional bracket ; group 4 , SEP + precoated bracket . After 30 days , premolars were extracted for orthodontic reasons and a Universal Instron Machine was used to apply an occlusal shear force directly to the enamel-bracket interface at a speed of 0.5 mm/min . The groups were compared using two-way analysis of variance . Mean results and st and ard deviation for the groups were : group 1 = 11.60 + /- 2.65 Mpa , group 2 = 9.79 + /- 2.71 Mpa , group 3 = 10.75 + /- 2.67 Mpa , and group 4 = 10.31+/- 2.70 Mpa . No difference was observed between the conventional etching and primer or SEP ( P = .948 ) . However , significant differences in bond strength were present between the uncoated and precoated brackets ( P = .032 ) . Considering the values required to withst and normal orthodontic forces ( 8 - 9 Mpa ) , it could be concluded that the SEP combined with adhesive precoated brackets showed adequate shear bond strength and may be suitable for clinical use OBJECTIVE To evaluate and compare the shear bond strengths of two adhesives using two types of brackets : a conventional and a self-ligating bracket system . MATERIAL S AND METHODS Sixty extracted human premolars were collected . The premolars were r and omly divided into three groups of 20 teeth . All three groups were direct bonded . Groups 1 and 2 used light-cured adhesive and primer ( Transbond XT ) with a conventional ( Orthos ) and a self-ligating bracket ( Damon 2 ) , respectively . Group 3 used a light-cured primer ( Orthosolo ) and a light-cured adhesive ( Blūgloo ) with a self-ligating bracket ( Damon 2 ) . The specimens were stored in distilled water at 37 degrees C for 40 + /- 2 hours , after which they were debonded and inspected for Adhesive Remnant Index ( ARI ) scoring . RESULTS The mean shear bond strength was 15.2 MPa for group 1 , 23.2 MPa for group 2 , and 24.8 MPa for group 3 . A one-way analysis of variance and post hoc Tukey test showed significant differences in bond strength ( P < .001 ) between group 1 and groups 2 and 3 but no significant difference ( P > .05 ) between groups 2 and 3 . A Weibull analysis demonstrated that all three groups provided sufficient bond strength with over 90 % survival rate at normal masticatory and orthodontic force levels . A Kruskal-Wallis test showed no significant difference ( P > .05 ) in ARI scores among all three groups . CONCLUSIONS All three groups demonstrated clinical ly acceptable bond strength . The Damon 2 self-ligating bracket exhibited satisfactory in vitro bond strength with both adhesive systems used The purpose of this study was to compare the debonding force of orthodontic brackets bonded with two conventional resin adhesives ( Resilience L3 and Light Bond ) and a resin-reinforced glass ionomer cement ( Fuji Ortho LC ) . For the in vitro part of the study , 80 extracted premolars were r and omly divided into four groups . In groups A and B , brackets were bonded to unetched enamel using Fuji Ortho LC cement in wet and dry conditions , respectively . In groups C and D , brackets were bonded to etched enamel using Resilience L3 and Light Bond , respectively .  Debonding force was determined using a servohydraulic testing machine at a crosshead speed of 1 mm/min . Data was analyzed using the ANOVA and Tukey-Kramer multiple comparison test at p<0.05 . A significant difference was found in debonding force between unetched Fuji Ortho LC and the two conventional resins . There was no significant difference between the two conventional resins or between unetched resin-reinforced glass ionomer in the wet and dry conditions . For the in vivo part of the study , 30 patients were r and omly assigned to one of the three bonding material groups . Bracket survival rates and distributions were obtained by following these patients for 1.2 years . Data was analyzed using the Kaplan-Meier product-limit estimates of survivorship function . Bond failure interface was determined using a modified adhesive remnant index ( ARI ) . These results showed no significant difference between survival rates and distributions among the three bonding material s with respect to the type of malocclusion , type of orthodontic treatment , or location of bracket . There were significant differences between survival distributions of males and females in the unetched Fuji Ortho LC group and among type of teeth in the conventional resin groups . The predominant mode of bracket failure for the unetched Fuji Ortho LC cement was at the enamel-adhesive interface , and for conventional resins , the enamel-adhesive interface and the bracket-adhesive interface . These results suggest that resin-reinforced glass ionomer cement can withst and occlusal and orthodontic forces despite having a bond strength lower than that of conventional resin adhesives The aim of the study was to evaluate and compare the clinical performance of adhesive precoated brackets ( APC ) with that of two types of uncoated bracket bases , Straight-Wire and Dyna-Lock , bonded using two types of orthodontic adhesives , Transbond XT , and Right-On .  Forty consecutive orthodontic patients entered the trial and 607 brackets were bonded . The incidence and site of first time bond failures were recorded over a period of 1 year . The time required for bonding was also recorded . The overall bond failure rate was 6.6 per cent . There were no significant differences between the failure rates of the five groups , or between the upper and lower arch . However , significantly more brackets failed on the left side than on the right . Premolar brackets were lost most often , whilst incisor brackets failed least . No association was found between bond failure and time elapsed since bonding . Bonding time was least with Right-On adhesive . There were no significant differences between bonding times using APC or Transbond . Results of the present study conflict with those of a previous ex vivo study by the authors , using the same material s and bonding technique . Suggested reasons for this are discussed 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 A new self-curing ( chemically cured ) resin-modified glass-ionomer cement , Fuji Ortho ( GC International ) , is based on the technology of hybrid glass-ionomer restorative material s and features chemical adhesion to tooth structure and long-term fluoride release . This article describes a 12-month clinical evaluation of  Fuji Ortho for the direct bonding of orthodontic ( metal ) brackets with System 1 + ( Ormco Corp. ) as a control . Three failures of Fuji Ortho occurred from a sample of 60 ( 5 % ) , with five failures of the composite resin from a sample of 60 ( 8.3 % ) . No statistical significance was seen between these results . Fuji Ortho is a satisfactory adhesive for the direct bonding of orthodontic brackets where there are no occlusal interferences One of the solutions for the problem of white spot lesions has been the application of a polymer coating to the labial enamel surface . The aim of this study is to find out whether the liquid polish BisCover affects the bond strength of brackets bonded with a light-cured system ( Transbond XT ) and a no-mix system ( Unite ) . St and ard stainless steel premolar brackets were bonded to 100 permanent human premolars r and omly divided into five equal groups . Two different enamel surface conditions were studied : dry and varnished with BisCover . For each enamel surface condition , two orthodontic adhesive systems were used : a light-cured system ( Transbond XT ) and a no-mix system ( Unite ) . All teeth were conditioned with 37 % phosphoric acid for 30 seconds , followed by thorough washing and drying . The teeth in groups 1 and 2 were bonded with Transbond XT and Unite , respectively . For groups 3 , 4 , and 5 , a thin layer of BisCover was applied to the etched enamel with a brush and light cured for 15 seconds . In group 3 , a thin layer of Transbond XT primer was applied , whereas in group 5 , no additional primer was used on BisCover . In groups 3 and 5 , the brackets were bonded with Transbond XT adhesive resin . Group 4 was bonded with no-mix Unite . Shear forces were applied to the sample s by a Zwick Universal test machine , and bond strengths measured in megapascals . The results revealed that shear bond strengths of the groups did not differ significantly from each other A longitudinal clinical trial was made in forty-two children to compare some commonly used techniques for  orthodontic bracket bonding .  A particular study design ( Figs. 1 and 5 ) allowed blind quadrantwise comparisons in the same patient of six different variables , including direct versus indirect bonding , adhesives of the filled diacrylate resin type with small versus large filler particles , and metal brackets with mesh-backed versus perforated bases . The same person bonded all brackets within one week and performed the orthodontic treatment by a friction-free edgewise light-wire technique . Efforts were made to minimize gingival irritation by using eccentrically placed brackets on small bases , by careful trimming of excess adhesives flash around the bases , and by directing much emphasis on oral hygiene measures . The plaque situation around the brackets and along the gingival margins and the gingival condition were assessed according to the criteria of the plaque and gingival index systems by a dental hygienist at each monthly visit during a test period of 6 months . The study demonstrated that both direct and indirect bonding with the different adhesives and bracket types could give clinical ly satisfactory results . Still , there were statistically significant differences in plaque retention , gingival inflammation , and bond strength . The bonding adhesive with small filler particles was more hygienic than and about as strong as two adhesives with larger , coarser filler particles . The mesh-backed brackets retained less plaque and gave stronger bonds than the brackets with perforated pads . Advantages of direct bonding over the indirect procedure were that ( 1 ) the bracket bases were fitted closer to the tooth surface ( which improved bond strength ) , ( 2 ) it was easier to work clean and to remove excess adhesive flash around the bracket bases ( to help prevent gingival inflammation and decalcification and facilitate debonding ) , and ( 3 ) the bonding adhesive constantly filled out the entire contact surface of the brackets ( thus avoiding artificial undercuts and deficiency areas which are prone to promote decalcification ) . A number of other clinical observations were also discussed 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 objective of this study was to compare 3  orthodontic adhesives  in the areas of shear-peel bond strength , location of adhesive failure , and extent of enamel cracking before bonding and after debonding of orthodontic brackets . The adhesives included a composite resin control ( Transbond XT ; 3M/Unitek , St Paul , Minn ) , a resin-modified glass ionomer cement ( Fuji Ortho LC ; GC America Corp , Alsip , Ill ) , and a polyacid-modified composite resin under dry and saliva-contaminated conditions ( Assure ; Reliance Orthodontic Products Inc , Itasca , Ill ) . Metal brackets were bonded to the buccal surfaces of 160 ( 4 groups of 40 ) human premolars . The bonded teeth were stored in deionized water at 37 degrees C for 30 days and thermocycled for 24 hours before debonding with a Universal Instron ( Instron Corp , Canton , Mass ) testing machine . The extent of cracking in the buccal surfaces was evaluated under 16x magnification before bonding and after debonding . Although the bond strength of the composite resin control ( 20.19 MPa ) was significantly greater ( P < .05 ) than that of the adhesives in the other groups , clinical ly acceptable shear-peel bond strengths were found for all adhesives ( Fuji Ortho LC = 13.57 MPa , Assure-dry = 10.74 MPa , Assure-wet = 10.99 MPa ) . The bond strength for the Assure adhesive was not significantly affected by saliva contamination . The sample of extracted premolars used in this study displayed a greater frequency of buccal surface enamel cracking ( 46.7 % ) than that reported in the literature for in vivo premolars ( 7.8%-10.2 % ) , which was possibly due to the extraction process . The frequency of enamel cracking in a subset of this sample ( n = 34 ) increased from 46.4 % at prebonding to 62.4 % at postdebonding as a result of the forces of debonding INTRODUCTION Many advantages of argon lasers have been reported , including high-speed orthodontic adhesive curing and less enamel demineralization . The purpose of this study was to compare bond strengths after curing with the argon laser ( 10 seconds ) and the conventional curing light ( 40 seconds ) in vivo and in vitro . METHODS Four premolars from each of 23 volunteers were r and omly assigned to either the argon laser group or the conventional light group for the in-vivo study . Shear bond strengths were measured after 14 days with custom- design ed debonding pliers . In-vitro bond strengths were measured by using 4 premolars from each of 25 volunteers .  Shear bond strength was measured after 14 days of thermocycling with the same protocol as the in-vivo study . Adhesive remnant index scores ( ARI ) were determined . RESULTS No significant differences were found in bond strengths according to curing method , dental arch , or sex . In-vivo results were significantly lower ( P < .05 ) than in-vitro results . A significant ( P < .05 ) difference in ARI scores between the curing methods was determined ; no significant correlation between mean bond strengths and ARI scores was determined . CONCLUSIONS Bond strength for argon laser curing is comparable to conventional light curing and is sufficient for clinical applications . Although the argon laser left more adhesive on the tooth surfaces on debonding , there was no increase in enamel surface fractures Objective : This in vitro study aim ed to compare the microleakage of orthodontic brackets between enamel-adhesive and adhesive-bracket interfaces at the occlusal and gingival margins bonded with different adhesive systems . Material s and Methods : A total of 144 human maxillary premolar teeth extracted for orthodontic reasons was r and omly divided into four groups . Each group was then further divided into three sub-groups . Three total-etching bonding systems ( Transbond XT , Greengloo and Kurasper F ) , three one-step self-etching bonding systems ( Transbond Plus SEP , Bond Force and Clearfil S3 ) , three two-step self-etching bonding systems ( Clearfil SE Bond , Clearfil Protectbond and Clearfil Liner Bond ) , and three self-adhesive resin cements ( Maxcem Elite , Relyx U 100 and Clearfil SA Cement ) were used to bond the brackets to the teeth . After bonding , all teeth were sealed with nail varnish and stained with 0.5 % basic fuchsine for 24 h. All sample s were sectioned and examined under a stereomicroscope to score for microleakage at the adhesive-enamel and adhesive-bracket interfaces from both occlusal and gingival margins . Statistical Analysis Used : Statistical analyses were performed with Kruskal-Wallis and Wilcoxon signed-rank tests . Results : The results indicate no statistically significant differences between the microleakage scores of the adhesives ; microleakage was detected in all groups . Comparison of the average values of the microleakage scores in the enamel-adhesive and adhesive-bracket interfaces indicated statistically significant differences ( P < 0.05 ) . The amount of the microleakage was higher at the enamel-adhesive interface than at the bracket-adhesive interface . Conclusions : All of the brackets exhibited some amount of microleakage . This result means that microleakage does not depend on the type of adhesive used Introduction : The bonding of orthodontic brackets and their failure rates by both direct and in-direct procedures are well-documented in orthodontic literature . Over the years different adhesive material s and various indirect bonding transfer procedures have been compared and evaluated for bond failure rates . The aim of our study is to highlight the use of a simple , inexpensive and ease of manipulation of a single thermo-plastic transfer tray and the use the of a single light cure adhesive to evaluate the bond failure rates in clinical situations . Material s and Methods : A total of 30 patients were r and omly divided into two groups ( Group A and Group B ) . A split-mouth study design was used , for , both the groups so that they were distributed equally with-out bias . After initial prophylaxis , both the procedures were done as per manufactures instructions . All patients were initially motivated and review ed for bond failures rates for 6 months . Results : Bond failure rates were assessed for over-all direct and indirect procedures , anterior and posterior arches , and for individual tooth . Z-test was used for statistically analyzing , the normal distribution of the sample in a spilt mouth study . The results of the two groups were compared and P value was calculated using Z-proportion test to assess the significance of the bond failure . Conclusion : Over-all bond failure was more for direct bonding . Anterior bracket failure was more in-direct bonding than indirect procedure , which showed more posterior bracket failures . In individual tooth bond failure , m and ibular incisor , and premolar brackets showed more failure , followed by maxillary premolars and canines Objective : To evaluate shear bond strength ( SBS ) of the orthodontic brackets bonded to fluorosed and nonfluorosed teeth using Light Bond with and without adhesion promoters and compare their enamel damages following debonding . Material s and Methods : In this study , 30 fluorosed ( Thylstrup and Fejerskov Index = 4–5 ) and 30 nonfluorosed teeth were r and omly distributed between two subgroups according to the bonding material s : Group 1 , fluorosed teeth bonded with Light Bond ; Group 2 , fluorosed teeth bonded with adhesion promoters and Light Bond ; Group 3 , nonfluorosed teeth bonded with Light Bond ; Group 4 , nonfluorosed bonded with adhesion promoters and Light Bond . After bonding , the SBS of the brackets was tested with a universal testing machine . Stereomicroscopic evaluation was performed by unbiased stereology in all teeth to determine the amount of adhesive remnants and the number and length of enamel cracks before bonding and after debonding . The data were analyzed using two-way analysis of variance , Kruskal – Wallis , Wilcoxon Signed Rank , and Mann – Whitney test . Results : While fluorosis reduced the SBS of orthodontic bracket ( P = 0.017 ) , Enhance Locus Ceruleus LC significantly increased the SBS of the orthodontic bracket in fluorosed and nonfluorosed teeth ( P = 0.039 ) . Significant increasing in the number and length of enamel crack after debonding was found in all four groups . There were no significant differences in the length of enamel crack increased after debonding among four groups ( P = 0.768 ) while increasing in the number of enamel cracks after debonding was significantly different among the four groups ( P = 0.023 ) . Teeth in Group 2 showed the highest enamel damages among four groups following debonding . Conclusion : Adhesion promoters could improve the bond strength of orthodontic brackets , but conservative debonding methods for decreasing enamel damages would be necessary 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 , respectively ) . Similar bond strengths were also found between the halogen light with a 20-second ( 16.1 + /- 3.6 MPa ) curing time and plasma arc light with 6 seconds ( 18.2 + /- 4.6 MPa ) of curing time after 24 hours of thermocycling . For the in-vivo study , no significant difference was found in bracket failure rates between the 2 light sources ( 4.9 % in both groups ) . No significant differences were found between ARI scores for the halogen light and the plasma arc light at either 30 minutes or 24 hours after debonding . CONCLUSIONS These results indicate that the plasma arc light with a 6-second curing time can produce similar bond strength and bracket-failure rates as the halogen light that requires a longer curing time OBJECTIVE To comparatively assess the failure rate of adhesive precoated ( APC ) self-ligating metal brackets bonded with two different enamel surface preparation techniques : self-etching primer ( SEP ) and conventional two-step etch and primer method ( CM ) . MATERIAL S AND METHODS Fifty-seven patients with complete permanent dentition were included in this study . A total of 1140 APC self-ligating brackets ( 3 M Unitek , Monrovia , Calif ) were bonded using a split-mouth design . For each patient , SEP ( Transbond Plus SEP , 3 M Unitek ) and CM ( 37 % phosphoric acid ) were used in alternate quadrants . All brackets were bonded by the same investigator after pumicing and rinsing of all of the teeth . The number , site , and date of first-time bracket failures were monitored throughout orthodontic treatment ( mean , 22 months ) . The survival rates of the brackets were estimated by Kaplan-Meier and log-rank tests ( P < .05 ) . The adhesive remnant index was used to determine the bond failure interface . RESULTS The bond failure rates were 2.97 % and 2.18 % for the CM and SEP , respectively . No statistically significant difference in failure rates was found between the groups . The bond failure sites were predominantly at the enamel-adhesive interface in both groups . CONCLUSION This long-term in vivo study showed that the combined use of SEP and the APC bracket system can be used effectively for bonding brackets after pumicing the enamel surfaces in clinical orthodontics As new adhesives , composite resins , and bonding techniques were introduced , orthodontists adopted some of these innovations and added them to their armamentarium . The purpose of this study was to compare the shear bond strength ( SBS ) of two adhesive material s ; one with an organically modified ceramic matrix , Admira ( Voco , Cuxhaven , Germany ) and another that contains the traditional Bis GMA matrix namely Transbond XT ( 3 M Unitek , Monrovia , Calif ) . The new material s have a lower wear rate and are more biocompatible than traditional composites . Forty molar teeth were r and omly divided into two groups : 20 teeth bonded with the Transbond adhesive system  and the other 20 teeth with the Admira bonding system .  Student 's t-test was used to compare the SBS of the two adhesives . Significance was predetermined at P < or = .05 . The results of the t-test comparisons ( t = 0.489 ) of the SBS indicated that there was no significant ( P = .628 ) difference between the two adhesives tested . The mean SBS for Admira was 5.1 + /- 3.3 MPa and that for Transbond XT was 4.6 + /- 3.2 MPa . It was concluded that the new material , Ormocer , which is an organically modified ceramic restorative material can potentially have orthodontic applications if available in a more flowable paste . These new material s are more biocompatible and have lower wear rate including bonding orthodontic brackets to teeth Background The purpose of this in-vitro study was to examine the effect of incorporating different concentrations of Zirconium oxide-Titanium dioxide ( ZrO2-TiO2 ) nanoparticles , which can have antibacterial properties , on the mechanical properties of an orthodontic adhesive . Methods ZrO2-TiO2 ( Zirconium oxide , HWNANO , Hongwu International Group Ltd , China ) -Titanium dioxide , Nanoshell , USA ) nanopowder were incorporated into orthodontic adhesive ( Transbond XT , 3 M Unitek , Monrovia , USA ) with different concentrations ( 0.5 % weight nonofiller and 1 % weight nanofiller ) . The size of nanoparticle was 70–80 nm for ZrO2 and less than 50 nm for TiO2 . For measuring the shear bond strength of the three groups of orthodontic adhesives [ Transbond ( control ) , Transbond mixed with 0.5 % weight ZrO2-TiO2 , and Transbond mixed with 1 % weight ZrO2-TiO2 ] , 30 freshly extracted human first premolars were used and bonded with stainless steel metal brackets ( Dentaurum ® , Discovery ® , Deutschl and ) , using the 3 orthodontic adhesives and 3 M Unitek ; Transbond TM Plus Self-Etching Primer ( 10 sample s in each group ) . The recorded values of compressive strength and tensile strength ( measured separately on 10 sample s of orthodontic adhesives ( add the 3 D size of sample , light cured for 40 s on both sides ) of each orthodontic adhesives ) , as well as the shear bond strength in Mega Pascal unit ( MPa ) were collected and exposed to one-way analysis of variance ( ANOVA ) and Tukey ’s post-hoc tests . Results orthodontic adhesive with 1 % weight ZrO2-TiO2 showed the highest mean compressive ( 73.42 ± 1.55 MPa , p : 0.003 , F : 12.74 ) , tensile strength ( 8.65 ± 0.74 MPa , p : 0.001 , F : 68.20 ) , and shear bond strength ( 20.05 ± 0.2 MPa , p : 0.001 , F : 0.17 ) . Conclusions Adding ZrO2-TiO2 nanoparticle to orthodontic adhesive increased compressive strength , tensile strength , and shear bond strength in vitro , but in vivo studies and r and omized clinical trials are needed to vali date the present findings The purpose s of this investigation were to compare the clinical performance of a resin-reinforced self-cured glass ionomer cement to a st and ard composite resin in the direct bonding of orthodontic brackets when bonded onto : a ) dry teeth and b ) teeth soaked with saliva . The two bonding agents were compared using a split-mouth design . In that , both systems were used for direct bonding of stainless steel brackets in every patient . Thirty-eight consecutive patients with fixed appliances were followed for a period of 12 months . The patients were r and omly divided into two groups : group A ( 11 patients ) and group B ( 27 patients ) . In group A , the performance of 220 stainless steel brackets was evaluated : 110 brackets were bonded with GC Fuji Ortho glass ionomer cement ( GC Industrial Co. , Tokyo , Japan ) onto dry teeth , and 110 bonded with System 1 + composite resin ( Ormco Corp. , Glendora , CA ) . In group B , the performance of 540 stainless steel brackets was evaluated : 270 brackets were bonded with GC Fuji Ortho onto teeth soaked with saliva , and 270 bonded with System 1 + . In group A , GC Fuji Ortho recorded an overall failure rate ( 34.5 % ) significantly higher ( p < 0.05 ) than System 1 + ( 9 % ) when applied onto completely dry teeth . Conversely , in group B , no statistically significant differences ( p > 0.05 ) between the failure rates of the two bonding agents were found when GC Fuji Ortho was used on teeth soaked with saliva . It was concluded , therefore , that GC Fuji Ortho shows clinical ly acceptable bond strengths when bonded onto moist teeth , but not when used on dry enamel . Both bonding agents failed mostly at the enamel/adhesive interface , without causing any enamel damage 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 aim of this study was to investigate the in vivo bonding of orthodontic brackets using two resin-modified glass poly(alkenoate ) cements and to compare them with a conventional light-cured diacrylate bonding agent .  Twenty consecutive patients attending for bond up appointments took part in this r and omized cross-mouth control study . Alternate quadrants were bonded with either Fuji Ortho LC or 3 M Multi-Cure . Transbond [ Adhesive Pre-Coated Brackets ( APC ) ] acted as the control in the other quadrants . Failed brackets were rebonded with the same material . Bond failure rates were collected over a 1-year period . The bond failure rates over 1 year were 7.2 per cent for Transbond ( APC ) , 5.9 per cent for 3 M Multi-Cure , and 5.8 per cent for Fuji Ortho LC . Statistically , there was no significant difference between the bond failure rates of the material s and there was no effect of time . This clinical investigation confirmed the suitability of the resin-modified glass poly(alkenoate ) cements under test as orthodontic bonding agents
The review reached no real conclusion apart from the lack of efforts to clinical ly evaluate the bonding efficiency of a wide range of orthodontic bracket-adhesive systems in terms of debonding force compared to laboratory-based in vitro and ex vivo studies
The aim of this study was to systematic ally review the available studies measuring the bond strength of  orthodontic bracket-adhesive system  under different experimental conditions in vivo .