***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: The aim of this in vitro was to evaluate the effects of tricalcium phosphate ( TCP ) and amorphous calcium phosphate ( ACP ) containing varnish material s and Er : YAG laser irradiation on enamel demineralization around orthodontic brackets . Forty extracted human premolar teeth were r and omly divided into four treatment groups ( i.e. , 10 in each group ) : ( 1 ) 5 % NaF-ACP varnish , ( 2 ) 5 % NaF-TCP varnish , ( 3 ) Er : YAG laser , and ( 4 ) control ( no treatment ) . Er : YAG laser was operated at a wavelength of 2.94 μm and the energy output was 80 mJ per pulse ; a pulse duration of 200 μsec and and a frequency of 2 Hz were used with water cooling . All sample s were then put into pH cycles . Surface microhardness values and representative SEM images were assessed . Surface microhardness values were evaluated using Kruskal-Wallis and Mann-Whitney U tests . The results revealed that demineralization was significantly lower in the TCP and ACP varnish groups , whereas mean surface microhardness values of the TCP varnish were found higher than the ACP ( P < 0.05 ) . TCP and ACP varnish material s were found effective for reducing enamel demineralization around orthodontic brackets . Use of Er : YAG laser irradiation as described in this study for inhibition of demineralization was found not satisfactory OBJECTIVE This clinical pilot study was conducted to investigate the effectiveness of argon laser irradiation to reduce  demineralization or loss of tooth structure  in vivo . SUMMARY BACKGROUND DATA In vitro research previously demonstrated the ability of argon laser irradiation to reduce demineralization or loss of tooth structure . METHODS Using the Ogaard model of producing demineralization , the experimental teeth were irradiated with argon laser of 250 mW ( producing approximately 12 J/cm2 ) prior to b and ing . Polarized light evaluation of the sectioned , extracted teeth was used to determine the amount of demineralization . RESULTS Results showed a 29.1 % reduction in demineralization in the experimental teeth as compared to the bilateral control teeth . CONCLUSION Low-power argon laser irradiation significantly reduced demineralization clinical ly Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more A prospect i ve clinical trial was carried out to compare argon laser-curing of a traditional light-activated composite resin with conventional visible light-curing in terms of bond failure rate and incidence of enamel decalcification . Forty-five patients with a total of 742 metal brackets bonded to the upper and /or lower teeth in a modified split-mouth design participated in the study . The adhesive ( Transbond XT ) on the control teeth was cured by conventional visible light for 40 seconds , and the experimental teeth were exposed to 10 seconds of 250 mW argon laser irradiation . The patients were monitored for a period of 14 months . Intraoral photographic slides of the maxillary anterior teeth ( 212 in total ) were taken at the beginning of treatment , after 12 months of treatment , following application of a plaque disclosing agent , and at the end of the observation period , following temporary debonding . Seven dentists used st and ardized rating systems to evaluate decalcification and plaque accumulation . The results of this study indicated that there were no significant differences between curing methods for the incidence of decalcification and plaque accumulation . However , the 10 second argon laser-curing method showed a statistically lower bond failure rate ( 2.4 per cent , P < 0.05 ) than the 40 second conventional visible light-curing method ( 5.7 per cent ) . It is concluded that the use of argon laser curing is superior to that of conventional light-curing with respect to bond failure and chairside time . However , the incidence of decalcification seems to be similar Objective This study was design ed to evaluate the effect of argon laser irradiation on development and progress of enamel demineralization around orthodontic brackets . Material s and Methods : Fifty caries-free , intact human premolars were r and omly assigned to one of the following five equal groups : Groups 1 ( control ) and 2 : The brackets were bonded using conventional halogen light for 40s and argon laser for 10s , respectively . Teeth in group 3 were lased with argon laser for 10s before bracket bonding with halogen light . Group 4 was the same as group 3 except that brackets were also bonded with argon laser . In group 5 sample s were bonded conventionally , immersed in an artificial caries solution for two days and then irradiated for 10s with argon laser . All sample s were subjected to demineralization by artificial caries solution for 10 days . After bracket removal , sample s were buccolingually sectioned and evaluated by polarized light microscopy . Decalcified lesion depth in each section was measured by a trained examiner in a blind fashion . Data were analyzed in SPSS 14 using one-way ANOVA and Tukey ’s HSD post hoc test . Results : The control group showed the greatest mean lesion depth while group 5 revealed the lowest . The laser-treated groups had significantly lower mean lesion depth compared with the control group ( P<0.05 ) except for group 4 ( P=0.192 ) . Conclusion : Argon laser irradiation for 10s before or during bracket bonding can increase caries resistance of intact and demineralized enamel Plaque control during the course of orthodontic treatment is not an easy task , and dental caries are not an unlikely complication . We examined the possibility of controlling dental caries with Nd-YAG laser irradiation in orthodontic patients . As a preliminary experiment , we used the Nd-YAG laser to irradiate an extracted tooth and then left it to soak in lactic acid . The decay of the tooth was evaluated with a scanning electron microscope ( SEM ) ; tooth decay was inhibited by the action of the laser . Twenty patients undergoing orthodontic treatment for early decalcification of the teeth ( white spot lesions ) were selected , and photographs were taken of their oral cavities . White spot lesions on the four incisors and two canines of the maxilla were traced on tracing paper , and their areas were calculated by computer . Ten of the patients received laser treatment and acidulated phosphate fluoride solution ( APF ) ; the other ten acted as the control group . Between 11 and 12 months later , we photographed the oral cavity as we had previously ; the white spot lesions were again traced and their areas calculated . The changes in the areas of the white spots of the laser-irradiated and control groups showed the following increases : laser-irradiated group , 1.41 times ; controls , 2.87 times . The difference was statistically significant . These results demonstrate that Nd-YAG laser irradiation with application of APF acts as an effective method of caries control during orthodontic treatment Enamel decalcification is a significant problem in orthodontic patients . The argon laser has been shown to reduce decalcification during an acidic challenge in vitro . The purpose of this study was to investigate the in vivo effects of argon laser irradiation on enamel decalcification during orthodontic treatment . Nine volunteers whose treatment plans included 4 first premolar extraction s were enrolled in the study . The 36 extracted premolars were assigned to 1 of the following 4 groups : group 1 , control group with no treatment ; group 2 ( pumice-laser ) , teeth were pumiced for 3 seconds and treated with a 325 mW , 5-mm diameter laser beam for 60 seconds ; group 3 ( pumice-etch-laser ) , teeth were pumiced for 3 seconds , acid-etched with 30 % phosphoric acid for 30 seconds , and treated for 60 seconds with laser ; and group 4 ( laser only ) , teeth were treated for 60 seconds with laser . A specially design ed ( oversized ) orthodontic b and was fitted on each of the premolars to create a pocket for decalcification . The b and s were cemented in place for 5 weeks . After extraction , the teeth were sectioned and examined under polarized light microscopy . Images of lesions were digitally analyzed and measured . Average lesion depths were calculated from 3 depth measurements recorded 10 microm apart . Average lesion area was calculated with the aid of imaging analysis software . Data were analyzed with analysis of variance ( P < .05 ) and Student t tests . Significant differences were found in lesion depth ( P < .001 ) and lesion area ( P < .01 ) among the 4 test groups . The average lesion depths were 15.93 + /- 9.31 microm ( control ) , 6.45 + /- 8.70 microm ( pumice-laser ) , 1.71 + /- 4.82 microm ( pumice-etch-laser ) , and 1.34 + /- 3.80 microm ( laser only ) . The average lesion areas were 1028.67 + /- 725.68 microm ( 2 ) ( control ) , 555.49 + /- 948.20 microm ( 2 ) ( pumice-laser ) , 79.91 + /- 226.03 microm ( 2 ) ( pumice-etch-laser ) , and 55.71 + /- 157.59 microm ( 2 ) ( laser only ) . The average lesion depth in the laser-only group was reduced by 94.1 % and the average lesion area was reduced by 94.4 % when compared with the control group . In the pumice-etch-laser group , the average lesion depth was reduced by 89.1 % and the average lesion area was reduced by 92.2 % when compared with the control group . There were no significant differences in lesion depth and lesion area between maxillary and m and ibular teeth ( P < .06 and P < .08 , respectively ) and between the teeth on the right and left sides ( P < .68 and P < .55 , respectively ) . These results show that argon laser irradiation is effective in reducing enamel decalcification during orthodontic treatment . Pumicing and etching do not appear to reduce the effect of laser on enamel solubility Argon lasers , because of their significant timesavings over conventional curing lights , have been investigated for use in bonding orthodontic brackets . They are also being investigated for their ability to confer demineralization resistance on enamel , which is of great interest in orthodontics . A two-part in vitro study on 86 human posterior teeth was conducted to determine the effects of a five-second argon laser exposure on shear bond strength and to evaluate the effects of a five- and 10-second argon laser exposure ( 250 mW ) on demineralization of enamel surrounding orthodontic brackets after exposure to an artificial caries bath . Brackets cured with the argon laser for five seconds yielded mean bond strengths similar to those attained with a 40-second conventional light-cured control ( n = 13 per group , 20.4 vs 17.8 MPa ) . Brackets cured with the argon laser for 10 seconds result ed in significantly lower mean lesion depth when compared with a visible light control ( n = 20 per group , 107.8 vs 137.2 microm , P = .038 ) . There were no statistically significant differences in lesion depth between the five-second argon laser and the visible light control groups . Overall , there was a 15 % and 22 % reduction in lesion depths for the five- and 10-second group , respectively . Poor correlations were found between the clinical appearance of decalcifications and their lesion depth .  Argon lasers used for bonding orthodontic brackets would save a significant amount of chair time while possibly conferring demineralization resistance upon the enamel Introduction : The aim of this study was to assess the caries-preventive potential of carbon dioxide ( CO2 ) laser application in conjunction with the use of titanium tetra fluoride solution on the enamel adjacent to bracket . Methods : Seventy-five freshly extracted bovine incisors were used . In order to attach the brackets , the area of examination was covered with adhesive tape to limit acid etching of the entire enamel surface . Metal orthodontic brackets for upper central were bonded to all the teeth following the manufacturer 's instruction . Then all the teeth were painted with 2 layers of acid-resistant nail varnish on all surfaces except the boxes area cervical to the brackets . The teeth were then r and omly divided into five groups ( n = 15 ) : control group ( C ) ; laser group ( L ) ; titanium group ( T ) ; laser-titanium group ( LT ) and titanium-laser group ( TL ) . The laser-titanium group was first irradiated with CO2 laser ( same as the L group ) then TiF4 solution was applied on the enamel ( same as the T group ) . Sample s in the TL group were first treated with TiF4 solution ( same as the T group ) and then irradiated with CO2 laser on the surface ( same as the L group ) . Then , the teeth were immersed in pH-cycling solutions . After that , the amount of calcium released into the two solutions ( de- and re-mineralization ) was measured with an atomic absorption spectroscopy . The data were analyzed by one-way Analysis of var-iance ( ANOVA ) and Tukey test . Results : Calcium loss in LT , TL and T groups were significantly lower than those in the L and C groups ( P < 0.0 
    Output:
    
Significant differences were observed in enamel demineralization between laser-irradiated and control groups for all laser types : argon laser , CO2 laser , neodymium-doped yttrium aluminum garnet ( Nd : YAG ) laser , and Optodan ® laser , except for argon laser application for curing bracket adhesives , where no statistically significant differences were noted .