***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 
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    Input: This clinical trial evaluated , over a 12-month period , the performance of brackets bonded to teeth etched and primed with Transbond Plus Self-Etching Primer ( SEP ) when compared with a conventional separate two-step etch and primer system .  Thirty-nine r and omly selected patients requiring fixed appliance therapy were entered into the study . R and om allocation of each etching system , along with a ' split-mouth cross-quadrant ' design was used . A total of 661 brackets were placed by two operators . The failure and survival rates of the brackets were determined for age and gender of the patients , each etching system , operator , mode of failure , tooth position in the dental arch , and number of manipulations prior to curing the adhesive . Statistical analysis showed that SEP had a significantly higher bond failure rate ( 11.2 per cent ) than the conventional etch and primer system ( 3.9 per cent ) at the P = 0.001 level . Cox 's proportional hazards regression showed the conventional etch and primer system to have a 60 per cent reduced chance of bracket failure over a 12-month observation period , while males had a 2.4 times increased risk compared with females . The predominant mode of failure was at the composite enamel interface for the SEP , while for the conventional etch and primer system , it was within the composite adhesive . No statistically significant differences were found for the failure rate with respect to the age of the patient , operator , tooth location , or the number of manipulations of the bracket . This in vivo study showed that brackets bonded using SEP had an increased clinical bond failure rate compared with the conventional , separate , etch and prime system The split-mouth design is a popular design in oral health research . In the most common split-mouth study , each of two treatments are r and omly assigned to either the right or left halves of the dentition . The attractiveness of the design is that it removes a lot of inter-individual variability from the estimates of the treatment effect . However , already about 20 years ago the pitfalls of the design have been reported in the oral health literature . Yet , many clinicians are not aware of the potential problems with the split-mouth design . Further , it is our experience that most statisticians are not even aware of the existence of this design . Since most of the critical remarks appeared in the oral health literature , we argue that it is necessary to introduce the split-mouth design to a statistical audience , so that both clinicians and statisticians clearly underst and the advantages , limitations , statistical considerations , and implication s of its use in clinical trials and advise them on its use in practice Glass ionomer orthodontic adhesives cause less enamel demineralization during fixed orthodontic appliance treatment than do traditional resin-based products . An in vivo r and omized clinical trial was performed comparing the clinical performance of a resin-modified glass ionomer ( RMGI ) adhesive with a no-mix , resin-based ( the control ) adhesive over a 12-month period . The split-mouth technique was used to analyze bracket retention , bracket failure causes , and mode of failure for both adhesives in 61 patients .  Bracket-failure rates were 10 % for the RMGI and 4 % for the resin-based adhesive . Both adhesives had 4 times more bracket failures when opposing occlusion was present . The resin-based product demonstrated a higher proportion of resin-to-enamel adhesive failures than did the RMGI . Compared with the resin-based adhesive , the RMGI-bracketed teeth showed improved clinical performance , no enamel surface loss , less enamel demineralization , and faster adhesive removal . However , the RMGI had a 2.6 times greater bracket-failure rate than did the resin-based product The aim of this study was to evaluate , over an 18-month period , the clinical performance of a self-etch adhesive [ Transbond Plus Self Etching Primer ( SEP ) , 3 M Unitek ] compared with a conventional adhesive that employs the etch- and -rinse approach ( Transbond XT , 3 M Unitek ) . One operator , using the straight-wire technique , bonded 567 metallic brackets to the teeth of 30 patients ( age range 12 - 18 years ) in a way that patients acted as self-control . The brackets were bonded following the manufacturers ' instructions except for the fact that the self-etch system was brushed for a longer time than recommended ( 10 - 15 seconds ) since previous investigations have reported that prolonged application times can improve the bonding efficacy of self-etch systems to enamel . The failure modes were visually classified into : adhesive-enamel , adhesive-bracket , and cohesive failure . The survival rates of the brackets were estimated by Kaplan-Meier and log-rank test ( P < 0.05 ) . The failure rates of the self-etch and conventional adhesives were 15.6 and 17.6 per cent , respectively . No significant differences in the survival rate were observed between the material s ( P > 0.05 ) . Most of the failures were cohesive and at the adhesive-enamel interface . There was no difference in the fracture debonding mode . These findings indicate that Transbond Plus SEP can be safely used for orthodontic brackets since the survival rates are similar to the conventional Transbond XT The aim of this study was to compare the clinical performance of a self-etching primer ( SEP ) with a conventional two-step etch and primer [ conventional method ( CM ) ] . The chair time required for bonding was also evaluated . Thirty-seven patients ( 14 males and 23 females ) with a mean age of 16 years 5 months were included in the study . Six hundred and seventy-two brackets were bonded by one operator using a split-mouth design , with either SEP ( Transbond Plus ) or CM ( Transbond XT ) . Bracket failure rates were estimated with respect to bonding procedure , dental arch , type of tooth ( incisor , canine , and premolar ) , and gender . The results were evaluated using the chi-square test . The survival rate of the brackets was estimated with Kaplan-Meier analysis . Bracket survival distributions with respect to bonding procedure , dental arch , type of tooth , and patient gender were compared with a log-rank test . Bond failure interface was determined with the adhesive remnant index ( ARI ) . The failure rates were 0.6 per cent for both bonding procedures . The failure and survival rates did not show significant differences between the bonding procedures , upper and lower dental arches , or gender . However , premolar brackets displayed a higher bond failure rate and a lower survival rate than incisor and canine brackets ( P < 0.05 ) . The mean bracket bonding time per tooth with SEP was significantly shorter than with CM ( P < 0.001 ) . No significant difference was observed for the ARI scores ( P > 0.05 ) . The results of this in vivo , r and omized , cross-mouth clinical trial demonstrated a high survival rate with Transbond Plus . This finding indicates that  SEP  can be effectively used for bonding of orthodontic brackets The purpose of this study was to measure the shear bond strength of stainless steel brackets bonded to enamel in vitro with a recently developed self-etching primer ( Transbond Plus Self Etching Primer , 3 M Unitek , Monrovia , Calif ) . Forty-eight extracted human teeth were obtained and r and omly divided into 4 groups of 12 : ( 1 ) control group with a conventional etchant and separate primer , ( 2 ) experimental group with the self-etching primer , left for 15 seconds before bonding , ( 3 ) same as group 2 , but with the primer left for 2 minutes before bonding , ( 4 ) same as group 2 , but with the primer left for 10 minutes before bonding . For each group , stainless steel brackets were mounted onto the prepared enamel , stored for 24 hours at 37 degrees C , and tested in a testing machine with a crosshead speed of 1 mm/min . There was no significant difference in the bond strength between the 4 groups as determined by analysis of variance ( ANOVA ) ( P < .05 ) . Under the conditions of these experiments , a 10-minute delay in bonding after application of the self-etching primer might not be deleterious to adhesion INTRODUCTION Our aim in this r and omized clinical trial was to compare the failure rates of orthodontic brackets by using 2 self-etching primers ( SEPs ) ( Transbond Plus [ 3 M Unitek , Seefeld , Germany ] and Clearfil Protect Bond [ Kuraray Medical , Okayama , Japan ] ) with a split-mouth design . Additionally , the effect of Clearfil Protect Bond was investigated regarding inhibition of plaque accumulation and demineralization . METHODS A total of 480 brackets were bonded in 24 patients with the SEPs .  The observation period was 12 months . One week after bonding and at every third recall , the plaque index and a visual rating of the enamel adjacent to the bracket were assessed at the lateral incisors and the first premolars . Additionally ,  DIAGNOdent  ( KaVo , Biberach , Germany ) values were measured . RESULTS Over the investigation time , 26 failures were recorded . Five occurred with the brackets bonded with Transbond Plus , and the rest with Clearfil Protect Bond ( P = 0.002 ) . The additionally observed parameters had no significant differences . CONCLUSIONS The failure rate with Clearfil Protect Bond was significantly higher . For our patients , who had adequate oral hygiene , there was no benefit with regard to plaque accumulation and prevention of demineralization with Clearfil Protect Bond 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 A clinical trial was conducted to compare bond failure when 15-second or 60-second acid etch times were used for the direct bonding of metal edgewise brackets . Bonds totaling 1174 were studied over a period of 6 to 13 months . Analysis of failure rate , bond survival time , and cement remaining after failure showed no statistical difference between the 15-second and 60-second etch groups . There were statistical differences in bond failures relating to the position of the tooth in the arch ( p less than 0.001 ) and to the type of bracket ( p less than 0.001 ) AIM To determine if microetching the m and ibular premolars and first molars prior to acid-etching reduced bracket failures during the first six months of orthodontic treatment . METHODS Sixty four patients with 384 m and ibular first molar and premolar brackets were used in a split-mouth study design . In each patient the teeth on one side were acid-etched and the contralateral teeth were microetched prior to acid-etching . The microetched side was alternated in successive patients . The brackets were indirect bonded to the teeth on both sides . First time bracket failures were recorded over a 6-month period . RESULTS Two brackets ( 1 per cent ) came loose on the microetched enamel side and four brackets ( 2.1 per cent ) failed on the conventionally acid-etched side . This difference was not clinical ly or statistically significant ( p = 0.41 ) . CONCLUSION The addition of microetching prior to acid-etching does not result in fewer bracket failures during the first six months of treatment Objective The primary objective of this prospect i ve clinical trial was to assess the clinical bond failure rates of orthodontic brackets bonded using a self-etching primer ( SEP ) , compared with brackets bonded using a conventional acid-etched technique with control adhesive ( Transbond ™ ) . A secondary aim was to investigate whether characteristics of the operator , patient or tooth bonded had any influence on bracket failure . Design Single-centre r and omized controlled clinical trial . Thirty-four patients were bonded , each being r and omly assigned to either the test or control adhesive . Setting NHS Hospital Orthodontic Department , Chester , UK . Subjects Orthodontic patients requiring fixed appliance treatment . Main outcome measures Bond failure . Main outcome results Failure rates over the initial 6-month period were 2.0 % ( Transbond ™ ) and 1.7 % ( SEP ) with no statistically significant difference between the two groups . Over the duration of the fixed appliance treatment , bond failure rates increased , but remained acceptable at 7.4 % ( TB ) and 7.0 % ( SEP ) , respectively . When operator , patient and tooth characteristics were analysed , only the bracket location was found to be significant . Maxillary brackets were more likely to fail than m and ibular brackets ( RR 0.47 % ; 95 % CI 0.22 , 1.03 ) . The failure rate for brackets in our study was low when compared with previous studies . Conclusions Both the acid-etched control and self-etching primer in combination with adhesive 
    Output:
    
We found low- quality evidence that was insufficient to conclude whether or not there is a difference in bond failure rate between SEPs and conventional etching systems when bonding fixed orthodontic appliances over a 5- to 37-month follow-up .