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: Objectives This study was conducted to evaluate a self-adhesive resin luting cement [ RelyX Unicem 3MESPE – RXU ] for  luting partial ceramic crowns ( PCCs )  with and without selective enamel etching in a prospect i ve , r and omized clinical trial . Material s and methods Thirty-four patients had received the intended treatment . Two PCCs ( Vita Mark II ; Cerec 3D ; Sirona ) had been placed in a split-mouth design : one with RXU without enamel etching ( RXU ) , the other with RXU with selective enamel etching ( RXU + E ) . Restorations were evaluated at baseline ( BL ) and after 12 , 24 , and 36 months ( USPHS criteria ) . For statistical analysis , the Chi-square test was applied ( α = 0.05 ) . Clinical survival of all restorations ( n = 68 ) after 3 years was determined using Kaplan – Meier analysis . Results Twenty three patients ( 12 male/11 female ) were available for clinical evaluation after 3 years . 19 RXU-PCCs were placed in molars , four in premolars , 18 RXU + E – PCCs in molars , five in premolars . Concerning clinical changes , no significant differences were found between luting strategies RXU/RXU + E at all recalls . Statistically significant changes over time were observed for marginal adaptation and marginal discoloration between BL and 36 m for RXU and RXU + E. For RXU + E , postoperative hypersensitivities decreased significantly from BL ( n = 6 ) to 36 m ( n = 0 ) . Of the 68 restorations originally included , eight RXU and four RXU + E restorations failed . At 3 years , Kaplan – Meier survival  of RXU was 72.9 % , that of RXU + E 87.6 % . Survival rates were not statistically significant different . Conclusions Although clinical survival of RXU + E is slightly better at 3 years , restorations of both groups perform similar with respect to clinical changes over time as evaluated by modified USPHS criteria . Clinical relevance The self-adhesive resin cement RXU can be used in conjunction with selective enamel etching , because survival rates of PCCs in the RXU + E group were not lower but , as a trend , even better than without enamel etching OBJECTIVES Clinical ly , the most easy-to-use composite cements are the so-called self-adhesive composite cements ( SAC 's ) . Hardly any data is however today available on the long-term bonding effectiveness of such luting composites . The purpose of this study was to evaluate the bond durability of different composite cements used to lute feldspathic ceramic blocks onto dentine . METHODS Four SAC 's ( Clearfil SA Cement , Kuraray ; G-CEM , GC ; SmartCem2 , Dentsply ; Unicem 3 M ESPE ) , one ' self-etch ' ( Clearfil Esthetic Cement , Kuraray ) and one ' etch- and -rinse ' ( Variolink ll , Ivoclar-Vivadent ) multi-step composite cement were used to lute feldspathic ceramic blocks ( Vita Mark II , Vita ) onto dentine surfaces . Teeth were distributed r and omly in 24 experimental groups according to two different surface-preparation techniques ( ' SMEAR-COVERED ' versus ' SMEAR-FREE ' ) and storage conditions ( ' IMMEDIATE ' versus ' AGED ' ) . Failure patterns were evaluated with a stereomicroscope , and afterwards imaged using Feg-SEM . Two additional specimens were processed for cement-dentine interfacial analysis using TEM . RESULTS A linear mixed effects statistical model revealed significant differences for the variables ' composite cement ' , ' surface preparation ' and ' ageing ' . All self-adhesive composite cements , except Unicem ( 3 M ESPE ) , did bond less favourably to fractured dentine . TEM revealed an ultra-structurally different interaction of the composite cements with ' SMEAR-COVERED ' and ' SMEAR-FREE ' dentine . CONCLUSION All SAC 's suffered most when luted to ' SMEAR-FREE ' ( fractured ) dentine , fortunately of no clinical relevance and most likely due to enhanced water sorption through the open tubules . When luted to ' SMEAR-COVERED ' dentine , all SACs appeared equally effective and durable as the ' etch- and -rinse ' and ' self-etch ' multi-step composite cements . Solely the SAC SmartCem2 ( Dentsply ) appeared clearly less favourable and consistent Purpose To compare the clinical success of a self-adhesive resin cement used in combination with different adhesive bonding systems with that of a conventional dual-cure resin cement . Methods The study was performed with 136 freshly extracted molars embedded in acrylic resin blocks and 136 IPS e.max Press discs . Teeth and discs were r and omly divided into four equal groups and cemented together using either RelyX ARC ( ARC ) , RelyX Unicem ( Unicem ) , RelyX Unicem+Adper-Prompt L-pop ( L-pop ) , or RelyX and Unicem+Total-etch ( Total-etch ) . Shear bond strength measurements were obtained before and after thermocycling . Following bond testing , the surfaces of one sample per subgroup ( thermocycled and non-thermocycled ) , were assessed using scanning electron microscopy ( SEM ) . Results Among the non-thermocylced subgroups , ARC exhibited the highest bond strength values , followed by Total Etch , Unicem and L-pop . ARC also exhibited the highest bond strength values among the thermocycled subgroups , followed by Unicem , Total-etch , and L-pop . SEM analysis clearly revealed the negative effects of thermo-cycling on the mechanical properties of adhesive agents . Conclusions RelyX Unicem may be preferable in many cases because of its simplified application and reduced technique-sensitivity Background To assess the immediate bond strength of a dual-cure adhesive resin cement to the hybridized dentin with different bonding systems . Material and Methods Fifty-six healthy human molars were r and omly divided into 7 groups ( n=8 ) . After 3 longitudinal sections , the central cuts were included in PVC matrix and were su bmi tted to dentin hybridization according to the groups : G1 - etch & rinse system with 3-step ( Apder ™ Scotchbond ™ Multi- Purpose , 3 M ESPE ) , G2 - etch & rinse system with 3-step ( Optibond ™ FL , Kerr ) , G3 - etch & rinse system with 3-step ( All-Bond 3 ® , Bisco ) , G4 - etch & rinse simplified system ( Adper ™ Single Bond 2 , 3 M ESPE ) , G5 - self-etching system with one step ( Bond Force , Tokuyama ) , G6 - universal system in moist dentin ( Single Bond Universal , 3 M ESPE ) , G7 - universal system in dry dentin ( Single Bond Universal , 3 M ESPE ) . Then all groups received the cementing of a self-adhesive resin cement cylinder ( Duo-link , Bisco ) made from a polypropylene matrix . In the evaluation of bond strength , the sample s were subjected to the microshear test and evaluated according to the fracture pattern by optical microscopy . Results The Kruskal-Wallis test suggests a statistically significant difference between groups ( p=0,039 ) , and Tukey for multiple comparisons , indicating a statistically significant difference between G3 and G4 ( p<0.05 ) . It was verified high prevalence of adhesive failures , followed by mixed failure and cohesive in dentin . Conclusions The technique and the system used to dentin hybridization are able to affect the immediate bond strength of resin cement dual adhesive . Key words : Adhesion , adhesive resin cement , adhesive systems , microshear OBJECTIVES The purpose of this study was to investigate the durability of extensive dentin-enamel-bonded posterior ceramic coverages  in a 15 years follow-up . METHODS All extensive dentin-enamel-bonded posterior partial and complete all-ceramic coverages placed during the period November 1992-December 1998 were included . In 121 patients , 252 coverages ( IPS Empress ) were placed . The adhesive bonding to dentin and enamel was performed with three 3-step and one 2-step etch and rinse bonding . In 106 restorations the classic Syntac was used in combination with the dual-cured resin composite Variolink . The other restorations were luted with the chemically cured resin composite Bisfil 2B and bonded with 3-step etch and rinse systems , classic Gluma ( 37 ) , Allbond 2 ( 57 ) , Syntac ( 32 ) or the 2-step etch and rinse system , One step ( 20 ) . The ceramics were evaluated yearly by modified USPHS criteria during 15 years . RESULTS Postoperative sensitivity was registered in 4 patients during bite forces lasting for 2 - 4 weeks . Fifty-five of 228 coverages ( 24.1 % ) failed . The mean observation period of the acceptable coverages was 12.6 years ( range 11 - 15 years ) . The main reasons for failure were lost restorations ( 18 ) , ceramic fracture ( 16 ) , and secondary caries ( 11 ) . Significant differences in failure rate were observed between the dentin bonding agents but not between the two luting agents . Ceramic  coverages placed on non-vital teeth failed in 39 % and on vital teeth in 20.9 % ( p=0.014 ) . Logistic regression indicated three significant predictors for failure of the coverages : gender and parafunctional habits of the patient and non-vitality of the tooth . SIGNIFICANCE The technique investigated showed advantages like less destruction of healthy tissue , and avoiding of endodontic treatment and /or deep cervical placement of restoration margins to obtain retention Indirect restorations need to be attached with adhesive luting agents to prevent them from becoming dislodged and provide adequate marginal sealing . The aim of this study was to evaluate bond strength to dentin of self-etching resin cements . MATERIAL S AND METHODS 75 flat dentin surfaces were r and omly distributed among 5 groups , according to cements used ; Group 1 : RelyxU100 ( 3M/ESPE ) , Group 2 : Bis Cem ( Bisco ) , Group 3 : Max Cem ( Kerr ) , Group 4 : SeT PP ( SDI ) and Group 5 : Relyx ARC ( 3M/ESPE ) , control . Ceramic test cylinders ( IPS Empress 2 / Ivoclar-Vivadent ) 4.1 mm across were prepared and attached to the dentin surfaces using the different cements . A constant 25N load was applied for 1 minute and they were light-polymerized . Following storage for 24 hours at 100 % humidity and 37 ° C , the specimens were tested for bond strength under shear strain in an Instron testing machine at a crosshead speed of 1 mm/minute ; at 7 , 14 and 21 days . Data were analyzed by ANOVA and Tukey 's test . There were significant differences between material s ( p < 0.0001 ) , but not between times or material /time interaction . RelyXARC ( Control Group ) had the highest bond strength ( 15.52 MPa ) . Among the self-etching cements , the best behavior was found for Relyx U100 ( 10.80MPa ) , followed by BisCem ( 6.36 MPa ) , MaxCem ( 5.45 MPa ) and SeTPP ( 3.17 MPa ) . The bond strength of the self-adhesive cements evaluated was lower than that for resin cements which require previous treatment of the dental substrate ( control group ) . This should be taken into account during clinical selection , in particular for tooth preparations with poor retention Objectives . To evaluate microleakage and absolute marginal discrepancy ( AMD ) and to assess correlation between AMD and microleakage with four resin luting cements . Material and Methods . 20 extracted human third molars were prepared for full-coverage crowns . 20 zirconia copings were made ( LAVA , 3 M ESPE ) and cemented . Specimens were r and omly allocated for each used type of cement into 4 groups , RelyX ® ( Rx ) , Multilink ® ( Mk ) , PANAVIA 2.1 ® ( P ) , and Maxcem ® ( Mx ) and immersed in 10 % safranin for 72 hours . 20x magnification lenses were used to observe microleakage areas ( μm2 ) and images software was used to measure AMD areas ( μm ) . Discrepancy and microleakage between the cements were compared with one-way ANOVA test with confidence interval of 95 % . Results . Rx Group showed microleakage has lowest value and AMD has highest value . P Group showed microleakage has the highest value and Mk Group presented AMD has lowest value . There were no significative differences between the cements . There were no linear correlations between microleakage and AMD ; however a complex regression statistical model obtained allowed formulating an association between both variables ( microleakage = AMD0,896 ) . Conclusions . No significative differences were found among 4 types of cements . No linear correlations between AMD and microleakage were found . Clinical Significance . AMD is not easily related to microleakage . Characteristics of cements are fundamental to decreasing of microleakage 
    Output:
    
agent
According to this review , the 3-step adhesive systems were the best performing and still are the gold st and ard for the cementing of indirect restorations .
In addition , it can be concluded that self-etched adhesive systems reduce the time spent in clinical practice , however at the interface level they behave as permeable membranes more susceptible to degradation
***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: Objectives This study was conducted to evaluate a self-adhesive resin luting cement [ RelyX Unicem 3MESPE – RXU ] for  luting partial ceramic crowns ( PCCs )  with and without selective enamel etching in a prospect i ve , r and omized clinical trial . Material s and methods Thirty-four patients had received the intended treatment . Two PCCs ( Vita Mark II ; Cerec 3D ; Sirona ) had been placed in a split-mouth design : one with RXU without enamel etching ( RXU ) , the other with RXU with selective enamel etching ( RXU + E ) . Restorations were evaluated at baseline ( BL ) and after 12 , 24 , and 36 months ( USPHS criteria ) . For statistical analysis , the Chi-square test was applied ( α = 0.05 ) . Clinical survival of all restorations ( n = 68 ) after 3 years was determined using Kaplan – Meier analysis . Results Twenty three patients ( 12 male/11 female ) were available for clinical evaluation after 3 years . 19 RXU-PCCs were placed in molars , four in premolars , 18 RXU + E – PCCs in molars , five in premolars . Concerning clinical changes , no significant differences were found between luting strategies RXU/RXU + E at all recalls . Statistically significant changes over time were observed for marginal adaptation and marginal discoloration between BL and 36 m for RXU and RXU + E. For RXU + E , postoperative hypersensitivities decreased significantly from BL ( n = 6 ) to 36 m ( n = 0 ) . Of the 68 restorations originally included , eight RXU and four RXU + E restorations failed . At 3 years , Kaplan – Meier survival  of RXU was 72.9 % , that of RXU + E 87.6 % . Survival rates were not statistically significant different . Conclusions Although clinical survival of RXU + E is slightly better at 3 years , restorations of both groups perform similar with respect to clinical changes over time as evaluated by modified USPHS criteria . Clinical relevance The self-adhesive resin cement RXU can be used in conjunction with selective enamel etching , because survival rates of PCCs in the RXU + E group were not lower but , as a trend , even better than without enamel etching OBJECTIVES Clinical ly , the most easy-to-use composite cements are the so-called self-adhesive composite cements ( SAC 's ) . Hardly any data is however today available on the long-term bonding effectiveness of such luting composites . The purpose of this study was to evaluate the bond durability of different composite cements used to lute feldspathic ceramic blocks onto dentine . METHODS Four SAC 's ( Clearfil SA Cement , Kuraray ; G-CEM , GC ; SmartCem2 , Dentsply ; Unicem 3 M ESPE ) , one ' self-etch ' ( Clearfil Esthetic Cement , Kuraray ) and one ' etch- and -rinse ' ( Variolink ll , Ivoclar-Vivadent ) multi-step composite cement were used to lute feldspathic ceramic blocks ( Vita Mark II , Vita ) onto dentine surfaces . Teeth were distributed r and omly in 24 experimental groups according to two different surface-preparation techniques ( ' SMEAR-COVERED ' versus ' SMEAR-FREE ' ) and storage conditions ( ' IMMEDIATE ' versus ' AGED ' ) . Failure patterns were evaluated with a stereomicroscope , and afterwards imaged using Feg-SEM . Two additional specimens were processed for cement-dentine interfacial analysis using TEM . RESULTS A linear mixed effects statistical model revealed significant differences for the variables ' composite cement ' , ' surface preparation ' and ' ageing ' . All self-adhesive composite cements , except Unicem ( 3 M ESPE ) , did bond less favourably to fractured dentine . TEM revealed an ultra-structurally different interaction of the composite cements with ' SMEAR-COVERED ' and ' SMEAR-FREE ' dentine . CONCLUSION All SAC 's suffered most when luted to ' SMEAR-FREE ' ( fractured ) dentine , fortunately of no clinical relevance and most likely due to enhanced water sorption through the open tubules . When luted to ' SMEAR-COVERED ' dentine , all SACs appeared equally effective and durable as the ' etch- and -rinse ' and ' self-etch ' multi-step composite cements . Solely the SAC SmartCem2 ( Dentsply ) appeared clearly less favourable and consistent Purpose To compare the clinical success of a self-adhesive resin cement used in combination with different adhesive bonding systems with that of a conventional dual-cure resin cement . Methods The study was performed with 136 freshly extracted molars embedded in acrylic resin blocks and 136 IPS e.max Press discs . Teeth and discs were r and omly divided into four equal groups and cemented together using either RelyX ARC ( ARC ) , RelyX Unicem ( Unicem ) , RelyX Unicem+Adper-Prompt L-pop ( L-pop ) , or RelyX and Unicem+Total-etch ( Total-etch ) . Shear bond strength measurements were obtained before and after thermocycling . Following bond testing , the surfaces of one sample per subgroup ( thermocycled and non-thermocycled ) , were assessed using scanning electron microscopy ( SEM ) . Results Among the non-thermocylced subgroups , ARC exhibited the highest bond strength values , followed by Total Etch , Unicem and L-pop . ARC also exhibited the highest bond strength values among the thermocycled subgroups , followed by Unicem , Total-etch , and L-pop . SEM analysis clearly revealed the negative effects of thermo-cycling on the mechanical properties of adhesive agents . Conclusions RelyX Unicem may be preferable in many cases because of its simplified application and reduced technique-sensitivity Background To assess the immediate bond strength of a dual-cure adhesive resin cement to the hybridized dentin with different bonding systems . Material and Methods Fifty-six healthy human molars were r and omly divided into 7 groups ( n=8 ) . After 3 longitudinal sections , the central cuts were included in PVC matrix and were su bmi tted to dentin hybridization according to the groups : G1 - etch & rinse system with 3-step ( Apder ™ Scotchbond ™ Multi- Purpose , 3 M ESPE ) , G2 - etch & rinse system with 3-step ( Optibond ™ FL , Kerr ) , G3 - etch & rinse system with 3-step ( All-Bond 3 ® , Bisco ) , G4 - etch & rinse simplified system ( Adper ™ Single Bond 2 , 3 M ESPE ) , G5 - self-etching system with one step ( Bond Force , Tokuyama ) , G6 - universal system in moist dentin ( Single Bond Universal , 3 M ESPE ) , G7 - universal system in dry dentin ( Single Bond Universal , 3 M ESPE ) . Then all groups received the cementing of a self-adhesive resin cement cylinder ( Duo-link , Bisco ) made from a polypropylene matrix . In the evaluation of bond strength , the sample s were subjected to the microshear test and evaluated according to the fracture pattern by optical microscopy . Results The Kruskal-Wallis test suggests a statistically significant difference between groups ( p=0,039 ) , and Tukey for multiple comparisons , indicating a statistically significant difference between G3 and G4 ( p<0.05 ) . It was verified high prevalence of adhesive failures , followed by mixed failure and cohesive in dentin . Conclusions The technique and the system used to dentin hybridization are able to affect the immediate bond strength of resin cement dual adhesive . Key words : Adhesion , adhesive resin cement , adhesive systems , microshear OBJECTIVES The purpose of this study was to investigate the durability of extensive dentin-enamel-bonded posterior ceramic coverages  in a 15 years follow-up . METHODS All extensive dentin-enamel-bonded posterior partial and complete all-ceramic coverages placed during the period November 1992-December 1998 were included . In 121 patients , 252 coverages ( IPS Empress ) were placed . The adhesive bonding to dentin and enamel was performed with three 3-step and one 2-step etch and rinse bonding . In 106 restorations the classic Syntac was used in combination with the dual-cured resin composite Variolink . The other restorations were luted with the chemically cured resin composite Bisfil 2B and bonded with 3-step etch and rinse systems , classic Gluma ( 37 ) , Allbond 2 ( 57 ) , Syntac ( 32 ) or the 2-step etch and rinse system , One step ( 20 ) . The ceramics were evaluated yearly by modified USPHS criteria during 15 years . RESULTS Postoperative sensitivity was registered in 4 patients during bite forces lasting for 2 - 4 weeks . Fifty-five of 228 coverages ( 24.1 % ) failed . The mean observation period of the acceptable coverages was 12.6 years ( range 11 - 15 years ) . The main reasons for failure were lost restorations ( 18 ) , ceramic fracture ( 16 ) , and secondary caries ( 11 ) . Significant differences in failure rate were observed between the dentin bonding agents but not between the two luting agents . Ceramic  coverages placed on non-vital teeth failed in 39 % and on vital teeth in 20.9 % ( p=0.014 ) . Logistic regression indicated three significant predictors for failure of the coverages : gender and parafunctional habits of the patient and non-vitality of the tooth . SIGNIFICANCE The technique investigated showed advantages like less destruction of healthy tissue , and avoiding of endodontic treatment and /or deep cervical placement of restoration margins to obtain retention Indirect restorations need to be attached with adhesive luting agents to prevent them from becoming dislodged and provide adequate marginal sealing . The aim of this study was to evaluate bond strength to dentin of self-etching resin cements . MATERIAL S AND METHODS 75 flat dentin surfaces were r and omly distributed among 5 groups , according to cements used ; Group 1 : RelyxU100 ( 3M/ESPE ) , Group 2 : Bis Cem ( Bisco ) , Group 3 : Max Cem ( Kerr ) , Group 4 : SeT PP ( SDI ) and Group 5 : Relyx ARC ( 3M/ESPE ) , control . Ceramic test cylinders ( IPS Empress 2 / Ivoclar-Vivadent ) 4.1 mm across were prepared and attached to the dentin surfaces using the different cements . A constant 25N load was applied for 1 minute and they were light-polymerized . Following storage for 24 hours at 100 % humidity and 37 ° C , the specimens were tested for bond strength under shear strain in an Instron testing machine at a crosshead speed of 1 mm/minute ; at 7 , 14 and 21 days . Data were analyzed by ANOVA and Tukey 's test . There were significant differences between material s ( p < 0.0001 ) , but not between times or material /time interaction . RelyXARC ( Control Group ) had the highest bond strength ( 15.52 MPa ) . Among the self-etching cements , the best behavior was found for Relyx U100 ( 10.80MPa ) , followed by BisCem ( 6.36 MPa ) , MaxCem ( 5.45 MPa ) and SeTPP ( 3.17 MPa ) . The bond strength of the self-adhesive cements evaluated was lower than that for resin cements which require previous treatment of the dental substrate ( control group ) . This should be taken into account during clinical selection , in particular for tooth preparations with poor retention Objectives . To evaluate microleakage and absolute marginal discrepancy ( AMD ) and to assess correlation between AMD and microleakage with four resin luting cements . Material and Methods . 20 extracted human third molars were prepared for full-coverage crowns . 20 zirconia copings were made ( LAVA , 3 M ESPE ) and cemented . Specimens were r and omly allocated for each used type of cement into 4 groups , RelyX ® ( Rx ) , Multilink ® ( Mk ) , PANAVIA 2.1 ® ( P ) , and Maxcem ® ( Mx ) and immersed in 10 % safranin for 72 hours . 20x magnification lenses were used to observe microleakage areas ( μm2 ) and images software was used to measure AMD areas ( μm ) . Discrepancy and microleakage between the cements were compared with one-way ANOVA test with confidence interval of 95 % . Results . Rx Group showed microleakage has lowest value and AMD has highest value . P Group showed microleakage has the highest value and Mk Group presented AMD has lowest value . There were no significative differences between the cements . There were no linear correlations between microleakage and AMD ; however a complex regression statistical model obtained allowed formulating an association between both variables ( microleakage = AMD0,896 ) . Conclusions . No significative differences were found among 4 types of cements . No linear correlations between AMD and microleakage were found . Clinical Significance . AMD is not easily related to microleakage . Characteristics of cements are fundamental to decreasing of microleakage 
    Output:
    