title: Comparison of microtensile bond strength to enamel and dentin of human, bovine, and porcine teeth. Total-etch versus self-etch adhesive: effect on postoperative sensitivity. Influence of sodium hypochlorite and EDTA on the microtensile bond strength of a self-etching adhesive system Effect of chemomechanical caries removal on bonding of self-etching adhesives to caries-affected dentin. Effect of collagen removal on shear bond strength of two single-bottle adhesive systems. Resin-dentin shear bond strength and interfacial ultrastructure with and without a hybrid layer. Influence of endodontic irrigants on bond strength of a self-etching adhesive. Influence of collagen removal on shear bond strength of one-bottle adhesive systems in dentin. SEM qualitative evaluation of four self-etching adhesive systems. Effect of a sodium hypochlorite gel on dentin bonding. The in vitro morphological effects of some current pre-treatments on dentin surface: a SEM evaluation.
abstract: PURPOSE To determine the bond strengths promoted by an adhesive system to human , bovine , and porcine enamel and dentin , and compare their etched micromorphology by scanning electron microscopy . MATERIAL S AND METHODS Thirty sound freshly extracted teeth were used in this study : ten human third molars , ten bovine incisors , and ten porcine molars . The crowns of human ( H ) , bovine ( B ) , and porcine ( P ) teeth were ground with 600-grit SiC paper to expose either enamel ( E ) or mid-depth dentin ( D ) surfaces . After application of the adhesive resin , composite crowns approximately 8 mm high were built up with TPH Spectrum composite . After 24 h of water storage , specimens were serially sectioned in the buccal-lingual direction to obtain 0.8 mm slabs , which were trimmed to an hourglass shape of approximately 0.8 mm2 at the bonded interface . Specimens were tested in tension in a universal testing machine ( 0.5 mm/min ) . Results were statistically analyzed with ANOVA and Tukey 's test at the 95 % confidence level . RESULTS Tukey 's test showed significant differences between bond strengths obtained on enamel and dentin ( p < 0.05 ) . However , there were no statistically significant differences in microTBS between human , bovine , and porcine teeth . SEM observations revealed a similar dentinal morphology for the three species . However , porcine enamel specimens presented a very different distribution of enamel prisms . CONCLUSION Bovine teeth proved to be possible substitutes for human teeth in either dentin or enamel bond testing . However , even though porcine teeth provided enamel and dentin bond strengths similar to human and bovine teeth , enamel morphology presented a very different configuration BACKGROUND Self-etching adhesives are believed to prevent postoperative sensitivity when used under posterior resin-based composite restorations . The authors tested a twofold hypothesis : a self-etch , or SE , adhesive would result in less postoperative sensitivity than a total-etch , or TE , adhesive ; an SE adhesive would result in poorer enamel marginal integrity than a TE adhesive . METHODS Patients were selected on the basis of requiring Class I and II restorations in molars and premolars . The authors placed 30 restorations with the SE material ( Clearfil SE Bond , Kuraray America , New York ) and 36 restorations with Prime & Bond NT ( Dentsply Caulk , Milford , Del. ) , which uses 34 percent phosphoric acid to etch enamel and dentin simultaneously . Preparations were of st and ard design , with all margins in enamel without beveling . Upon rubber dam isolation , the authors conditioned the enamel and dentin walls with the self-etching primer ( for Clearfil SE Bond ) or etched with the proprietary 34 percent phosphoric acid ( for Prime & Bond NT ) , followed by application of the corresponding dentin adhesive . Teeth were restored with the proprietary hybrid resin-based composite indicated for posterior restorations : Clearfil AP-X for Clearfil SE Bond or Esthet-X Micro Matrix Restorative for Prime & Bond NT . The restored teeth were evaluated preoperatively and at two weeks , eight weeks and six months postoperatively for sensitivity to cold ( ice ) , air and masticatory forces , as well as for marginal discoloration . RESULTS Analysis of variance revealed no statistically significant differences in postoperative sensitivity between the SE and TE material s at any recall time . Marginal discoloration was rated as " absent " for all restorations at six months . Only one tooth displayed sensitivity to occlusal forces at six months . CONCLUSION The SE adhesive did not differ from the TE adhesive in regard to sensitivity and marginal discoloration . CLINICAL IMPLICATION S Postoperative sensitivity may depend on the restorative technique rather than on the type of dentin adhesive used Chemical substances used during biomechanical preparation of root canals can alter the composition of dentin surface and affect the interaction with restorative material s. Objective The purpose of this study was to evaluate the microtensile bond strength ( µTBS ) of a self-etching adhesive system to dentin irrigated with sodium hypochlorite ( NaOCl ) and ethylenediaminetetraacetic acid ( eDTA ) . Material and Methods Thirty human third molars were sectioned 3 mm below the occlusal surface , polished with 600- to 1200-grit silicon carbide papers , and r and omly divided into 3 groups : G1 ( control ) : no irrigating solution ; G2 : 1 % NaOCl ; and G3 : 1 % NaOCl followed by the application of 17 % eDTA . The specimens received the self-etching adhesive system ( XeNO III - Dentsply ) , restored with microhybrid composite resin ( Z250 - 3 M ESPE ) , sectioned and trimmed to create 4 hourglass-shaped slabs of each tooth . The slabs were tested in microtensile strength in a universal testing machine ( emic DL 2000 ) at a crosshead speed of 0.5 mm/min until fracture . The results were analyzed statistically by ANOVA and Newman-Keuls test . Results Mean µTBS values and st and ard deviations in MPa were : G1 = 11.89 ± 4.22 ; G2 = 19.41 ± 5.32 ; G3 = 11.34 ± 4.73 . 1 % NaOCl  increased the adhesive resistance significantly ( p<0.001/ F=22.5763 ) . The application of 1 % NaOCl/17 % eDTA result ed in statistically similar µTBS to the control group . Conclusions None of the irrigants affected negatively the µTBS of XeNO III to dentin . The use of 1 % NaOCl alone result ed in higher bond strength than the other treatments . The combination of 1 % NaOCl and 17 % eDTA produced similar bond strength to that of untreated dentin PURPOSE To evaluate the effect of enzyme-based ( Papacárie ) and sodium-hypochlorite-based ( Carisolv ) chemomechanical caries removal methods on bonding of self-etching adhesives to caries-affected dentin , in comparison to the st and ard rotary-instrument caries removal method . MATERIAL S AND METHODS Seventy-eight carious permanent molars exhibiting frank cavitation into dentin were used . Forty-eight teeth were r and omly divided into three groups , according to the caries excavation methods : ( i ) Papacárie , ( ii ) Carisolv and ( iii ) a round steel bur . After caries removal , each group was subdivided into two groups for two-step ( Clearfil SE Bond ) or one-step ( Clearfil S3 Bond ) self-etching adhesive application and resin composite buildups . Bonded specimens were sectioned into beams for microtensile bond strength testing . Bond strength data were analyzed using three-way ANOVA and Tukey 's test . For interfacial nanoleakage evaluation using a field-emission scanning electron microscope , caries was similarly removed from the remaining thirty carious molars , bonding was performed as for bond strength testing , and the teeth were sectioned . RESULTS RESULTS of three-way ANOVA revealed that bond strength was significantly affected by " adhesive " ( p<0.001 ) and " dentin " ( p<0.001 ) , but not " caries excavation methods " ( p>0.05 ) . The bond strength of the two-step self-etching adhesive was significantly higher than that of the one-step self-etching adhesive ( p<0.001 ) . Conversely , the bond strength of self-etching adhesives to sound dentin was significantly higher than to residual caries-affected dentin ( p<0.001 ) . Greater silver penetration was observed in the bonded interfaces of residual caries-affected dentin and in interfaces bonded with the one-step self-etching adhesive vs those bonded with the two-step self-etching adhesive . CONCLUSION Chemomechanical caries removal did not affect the bonding of self-etching adhesives to caries-affected dentin as compared to caries excavation with rotary instruments This study evaluated the effect of collagen removal on the shear bond strength for two single-bottle adhesive systems . The ultrastructure of the dentin after treatments and the dentin-resin interface were examined under SEM . The buccal and lingual surfaces of 80 extracted human third molars were ground to expose dentin . Teeth were r and omly assigned to four groups and received the following treatments : Group 1(P&B 2.1 ) , Prime & Bond 2.1 adhesive was applied according to the manufacturer 's directions and Restorative Z100 composite resin was bonded to the dentin surface ; Group 2 ( P&B 2.1/NaOCl ) , the same procedures were followed as for Group 1 except that the surfaces were treated with 10 % sodium hypochlorite ( NaOCl ) for one minute after acid conditioning ; Group 3 ( SB ) , Single Bond ( 3 M ) was applied according to the manufacturer 's recommendations ; Group 4 ( SB/NaOCl ) , the same procedure was followed for Group 2 , using Single Bond . The specimens were stored in humidity at 37 degrees C for 24 hours and tested in a shear mode at a crosshead speed of 0.5 mm/minute . The Kruskal-Wallis test and Multiple Comparisons were used for statistical analysis of the data . A one-minute exposure of dentin to 10 % NaOCl following acid conditioning result ed in a significant increase of the dentin shear bond strength for Prime & Bond 2.1 . The same treatment for Single Bond result ed in a significant reduction in bond strength . Groups 1 and 3 were not statistically different from each other . The presence of a collagen layer result ed in the formation of a hybrid layer and similar values of adhesion for both adhesive systems . The results may suggest that collagen removal improves the bond strength for this acetone-based adhesive system but several such systems would need to be investigated The purpose of this study was ( 1 ) to evaluate the effect of a 2-minute exposure of 5 % NaOCl following acid conditioning of the dentin on the shear bond strength for two adhesive systems and ( 2 ) to examine the ultrastructure of the resindentin interface under SEM . The mesial and distal surfaces of 28 extracted human third molars were ground to expose dentin , then polished with 600-grit SiC. Teeth were r and omly assigned to four test groups ( n = 14 ) and received the following treatments : Scotchbond Multi- Purpose (SBMP)-- Sample s were conditioned with 37 % phosphoric acid , rinsed and left moist , SBMP primer and adhesive were applied according to the manufacturer 's directions , and Restorative Z-100 composite resin was bonded to the dentin surface . SBMP/NaOCl -- The same procedures were followed as for SBMP except the surfaces were treated with 5 % NaOCl for 2 minutes , after acid conditioning . All-Bond 2 (AB2)--The same technique was followed as for SBMP , using AB2 according to the manufacturer 's recommendations . AB2/NaOCl -- The same procedure was followed as for SBMP/NaOCl , using AB2 . Specimens were thermocycled in a water bath 300 times between 5 degrees-55 degrees C , then sheared in a Zwick Universal Testing Machine . A one-way ANOVA and Duncan 's Multiple Range Test were used for statistical analysis of the data . A 2-minute exposure of dentin to 5 % NaOCl following acid conditioning of the dentin had no significant effect on the dentin shear bond strength for Scotchbond Multi- Purpose , but significantly increased the bond strength of All-Bond 2 specimens . The interfacial structure of the dentin to resin bond for two dentin treatments and two adhesive systems was studied morphologically under the scanning electron microscope . Argon ion beam etching and acid demineralization clearly revealed the hybrid layer for the conventional treatment with phosphoric acid and indicated an absence of this resin-impregnated collagen network in those specimens treated with both phosphoric acid and NaOCl The aim of this in vitro study was to evaluate the bond strength of a self-etching adhesive system to dentine irrigated with sodium hypochlorite ( NaOCl ) , chlorhexidine solution ( CX ) and ethylene diamine tetra acetic acid ( EDTA ) by microtensile testing . Sixty human third molars were sectioned 3 mm below the occlusal level and then r and omly divided into six groups : G1(control ) , without irrigant solution ; G2 , 1 % NaOCl ; G3 , 1 % NaOCl followed by the application of 17 % EDTA ; G4 , 2 % CX ; G5 , 2 % CX followed by the application of 17 % EDTA and G6 , 17 % EDTA . The specimens received the self-etching adhesive system were restored with composite resin , then sectioned and trimmed to obtain four hourglass-shaped slabs from each tooth . The specimens were su bmi tted to the microtensile test in a Universal Testing Machine at a crosshead speed of 0.5 mm min(-1 ) until fracture . The results were su bmi tted to statistical analysis by anova /Newman-Keuls . The means and st and ard deviations ( MPa ) were : G1 , 26.88 ( ±3.81 ) ; G2 , 19.08 ( ±3.89 ) ; G3 , 18.16 ( ±2.21 ) ; G4 , 18.14 ( ±4.32 ) ; G5 , 34.30 ( ±3.32 ) ; G6 , 13.61 ( ±1.21 ) . It was concluded that the application of 2 % CX followed by the application of 17 % EDTA result ed in increasing the bond strength of the self-etching adhesive system to dentine , when compared with the results obtained for the other tested groups PURPOSE The aim of this study was to evaluate the influence of collagen removal on shear bond strength ( SBS ) of three hydrophilic one-bottle adhesive systems in dentin . MATERIAL S AND METHODS Test specimens were taken from one-hundred twenty bovine incisors . The specimens were debrided , polished with 320- to 600-grit Al2O3 paper , and r and omly divided into 6 groups ( n = 20 ) : G1 : acid/10 % NaOCl + Bond 1 ( B1H ) ; G2 : acid + Bond 1 applied according to manufacturer 's instructions ( B1 ) ; G3 : acid/10 % NaOCl + Optibond Solo ( OSH ) ; G4 : acid + Optibond Solo used according to manufacturer 's instructions ( OS ) ; G5 : acid/10 % NaOCl + Single Bond ( SBH ) ; G6 : acid + Single Bond used according to manufacturer 's instructions . In all groups , dentin was etched for 15 s , rinsed , and dried . In groups 1 , 3 , and 5 , the 10 % NaOCl was applied with a dwell time of 60 s , rinsed , and dried . In all groups , the adhesive systems were applied and light cured , and then a restorative composite resin ( Z-100 ) was inserted in a teflon matrix and cured . The specimens were stored in humid conditions for 7 days at 37 degrees C. The SBS tests were performed in an EMIC universal testing machine with a crosshead speed of 0.5 mm/min . The mean bond strengths in MPa ( + /- SD ) were analyzed with two-way ANOVA and Tukey 's test ( alpha = 0.05 ) . RESULTS The application of NaOCl significantly increased the SBS values of all systems except Optibond Solo . The means ( SD ) for adhesive systems with 10 % NaOCl treatment were : SBH = 14.28 (4.21)a ; B1H = 14.39 (3.61)a ; OSH = 10.35 (5.74)a ; and values without 10 % NaOCl were : SB = 10.35 (2.95)a ; B1 = 9.38 (3.10)a ; OS = 9.79 (3.48)b . Different superscripts indicate significant difference . CONCLUSION The removal of collagen increased the strength of dentin bonding , depending on the adhesive system used AIM Recently , there has been a tendency to simplify bonding procedures . Current self-etching adhesives combine conditioning , priming and bonding functions thus reducing technique-sensitivity as well as the risk of making errors . Another important advantage of this approach is that it allows the resin to etch and infiltrate the substratum simultaneously thus reducing the risk of any discrepancy between these 2 processes . The aim of this study was to evaluate the bonding quality of 4 self-etching adhesives both on dentin and enamel using SEM analysis . METHODS Twenty caries-free molars were used . The a prisma tic enamel layer was removed from the internal and external slopes of the vestibular cusps using a diamond bur . Each molar was then transversally cut just above the pulp chamber using a diamond saw ( composhave 4255 Intensiv ) thus obtaining twenty coronal fragments and 20 radicular fragments . Radicular and coronal fragments were then r and omly divided into 5 groups . Each group consisted of 8 specimens : 4 coronal and 4 radicular ones . A different adhesive system was used for each group following the manufacturer 's directions . Each group underwent the same treatment : a thin layer of flowable composite was applied and then polymerized . Subsequently , a single 2 mm layer of microhybrid composite was added . The coronal and radicular portions were longitudinally cut to show the ground enamel/adhesive , unground enamel/adhesive and dentine/adhesive interfaces . Eighty specimens were obtained and prepared for SEM observation . Forty specimens with an adhesive/enamel interface and 40 with an adhesive/dentine interface . RESULTS The interfacial exam frequently showed gaps between the substratum and the restoration . The final etching was generally satisfactory on ground enamel , while it was poor on unground enamel . Sometimes gaps were evident at the adhesive interface in dentin specimens . The tested adhesive systems produced a suitable hybrid layer and a lot of resin-tags were present . CONCLUSIONS Self-etching adhesives showed an adequate adhesion to dentin . However , while they provided encouraging results on ground enamel they did not show to be dependable on unground enamel UNLABELLED It has been suggested that the hybrid layer ( HL ) does not play any important role in the mechanism of adhesion to dentin . To substantiate this hypothetical in significance of the HL , sodium hypochlorite ( NaOCl ) has been used to remove collagen from etched dentin prior to bonding . OBJECTIVES The present study was conducted to determine the effect of a commercial 10 % NaOCl gel on the dentin shear bond strengths and HL ultra-morphology of two simplified dentin adhesives . The null hypothesis tested was that treatment of etched dentin collagen with NaOCl would not compromise dentin bonding . METHODS The labial surface of eighty bovine incisors was polished to expose middle dentin . The specimens were r and omly assigned to two total-etch adhesive systems ( N = 40 ) : Prime&Bond NT ( Dentsply Caulk ) ; and  Single Bond ( 3 M Dental Products Division ) . After rinsing off the etchant , one drop of 10 % NaOCl ( AD Gel , Kuraray Ltd. ) was applied to the etched dentin surface and left for 0 ( control ) , 15 , 30 , or 60 s. The gel was rinsed off with water and the dentin surface kept visibly moist prior to the application of the adhesive as per manufacturer 's instructions . The respective composite resin was subsequently applied and light-cured . After 24 h in water at 37 degrees C , the specimens were thermocycled for 500 cycles in baths kept at 5 and 55 degrees C and the shear bond strengths measured . The data were analyzed with two-way ANOVA . For TEM , sixteen dentin disks were taken from middle dentin of extracted human third molars , assigned to the eight treatment sequences , and observed . RESULTS The increase in the  NaOCl application time result ed in a progressive decrease in shear bond strengths for both dentin adhesives . For Single Bond , the application of AD Gel for 60 s result ed in a reduction of bond strengths to 38 % of that obtained for the control . For Prime&Bond NT , the mean bond strength obtained when AD Gel was applied for 60 s was 31 % of that obtained for the control . The application of AD Gel result ed in distinct morphology for each one of the two adhesives tested . For Single Bond , the general morphology of the collagen network was maintained , regardless of the deproteinization time . The interfibrillar space within the collagen network increased with increasing deproteinization times . For Prime&Bond NT , the general appearance of the HL was maintained for deproteinization times of 15 and 30 s. When the NaOCl gel was applied for 60 s , the morphological appearance of the HL lost its fibrillar arrangement . While remnants of the collagen fibers were observed in one of the dentin disks , the other specimen showed an amorphous structure without any discernible HL morphological features . SIGNIFICANCE The integrity of the collagen fibrils left exposed upon acid-etching plays a major role in the mechanism of adhesion of the specific adhesive systems tested in this study . The intermingling of the adhesive monomers with the filigree of collagen fibers or HL should still be considered the paramount dentin bonding mechanism This in vitro study morphologically evaluated the effect of some current surface pre-treatments on dentin , using scanning electron microscopy , and related these morphological alterations to clinical implication s. The labial surfaces of 30 bovine lower incisors were ground to obtain a flat dentin surface and were finished with 600-grit SiC paper to produce st and ardized smear layers . The teeth were r and omly divided into six groups of five each . Group 1 was the control group , smear layer covered dentin ; Group 2 was etched with 37 % phosphoric acid ( PA ) for 15 seconds ; Group 3 , 37 % PA for 15 seconds , followed by 10 % NaOCl for 60 seconds ; Group 4 , 10 % NaOCl for 60 seconds ; Group 5 , a self-etching primer ( Clearfil SE Bond , CSEB-primer ) was applied for 20 seconds ; Group 6 , CSEB-primer for 20 seconds , followed by NaOCl for 60 seconds . The specimens were fixed , dehydrated , dried and analyzed by SEM . Treatment with 37 % PA removed the smear layer , funneled the tubules and result ed in a collagen-rich surface which appeared to have collapsed in its outermost part , producing a dense surface layer covered with silica particles . When 37 % PA treatment was followed by 10 % NaOCl , the collagen network was removed to reveal an eroded , rough mineral surface with numerous lateral branches and larger than normal tubular orifices . The action of 10 % NaOCl on the smear layer-covered dentin showed no significant alteration in surface morphology . The treatment with CSEB-primer dissolved the smear layer but only partially dissolved the smear plugs . The tubules did not present the typical funnel shape seen following PA treatment . These morphological aspects on dentin surface must influence bonding results . The dentin surface alterations produced by PA appeared to be a very severe demineralization pattern , quite irregular and less permeable to monomer infiltration , while the surface provided by the self-etching primer appeared to be a more uniform , less porous surface , and the association with simultaneous monomer infiltration may reduce the occurrence of mistakes in clinical bonding procedures
target: Conclusions In light of the currently available scientific evidence , dentin surface pretreatment with deproteinizing agents does not enhance the bonding of SE adhesives to dentin .
  The HOCl deproteinizing agent exhibited minimal adverse effects on bonding to dentin in comparison with NaOCl solutions
background: Objectives The aim of this systematic review was to critically analyze previously published studies of the effects of dentin surface pretreatment with deproteinizing agents on the bonding of  self-etch ( SE ) adhesives to dentin .
  Additionally , a meta- analysis was conducted to quantify the effects of the above-mentioned surface pretreatment methods on the bonding of SE adhesives to dentin .