Both synthetic and naturally derived crosslinkers have been found to exhibit significant effects in biomodification of dentine via their multiple interactions with the dentine matrix .
A stable matrix network or a durable hybrid layer in dentine bonding could be achieved , where the dentine collagen fibrils show improved biochemical and biomechanical properties and enzymatic biodegradation is reduced .
This aim of this review is to explore the current research related to  crosslinking agents used on dentine .
Resin bond strength to water versus ethanol-saturated human dentin pretreated with three different cross-linking agents
Context : Resin-dentin bonds are unstable owing to hydrolytic and enzymatic degradation . Several approaches such as collagen cross-linking and ethanol-wet bonding ( EWB ) have been developed to overcome this problem . Collagen cross-linking improves the intrinsic properties of the collagen matrix . However , it leaves a water-rich collagen matrix with incomplete resin infiltration making it susceptible to fatigue degradation . Since EWB is expected to overcome the drawbacks of water-wet bonding ( WWB ) , a combination of collagen cross-linking with EWB was tested . Aim : The aim of this study was to compare the effect of pretreatment with different cross-linking agents such as ultraviolet A (UVA)-activated 0.1 % riboflavin , 1 M carbodiimide , and 6.5 wt% proanthocyanidin on the immediate and long-term bond strengths of an etch and rinse adhesive system to water- versus ethanol-saturated dentin within clinical ly relevant application time periods . Setting s and Design : Long-term in vitro study evaluating the microtensile bond strength of adhesive-dentin interface after different surface pretreatments . Subjects and Methods : Eighty freshly extracted human molars were prepared to expose dentin , etched with 37 % phosphoric acid for 15 s rinsed , and grouped r and omly . They were blot-dried and pretreated with different cross-linkers : 0.1 % riboflavin for 2 min followed by UVA activation for 2 min ; 1 M carbodiimide for 2 min ; 6.5 wt% proanthocyanidin for 2 min and rinsed . They were then bonded with Adper Single Bond Adhesive ( 3 M ESPE ) , by either WWB or EWB , followed by resin composite build-ups ( Filtek Z350 , 3 M ESPE ) . Bonded specimens in each group were then sectioned and divided into two halves . Microtensile bond strength was tested in one half after 24 h and the other after 6 months storage in artificial saliva . Statistical Analysis Used : Analysis was done using SPSS version 18 software ( SPSS Inc. , Chicago , IL , USA ) . Intergroup comparison of bond strength was done using ANOVA with post hoc Tukey 's test , and intragroup comparison was done using paired t-test . Results : The microtensile bond strength of cross-linked groups was higher compared to control group ( P < 0.001 ) . EWB showed much higher bond strength values on cross-linked dentin compared to noncross-linked dentin . UVA-activated riboflavin group exhibited highest bond strengths followed by carbodiimide and proanthocyanidin groups , respectively , on both water- as well as ethanol-saturated dentin . Even after 6 months storage , cross-linked groups showed significantly higher values compared to initial bond strength values of control group ( P < 0.001 ) . Conclusions : 0.1 % riboflavin pretreatment of dentin followed by UVA activation for 2 min exhibited highest increase in bond strength values at 24 h and least reduction in bond strength values after 6 months storage compared to other groups . Biomodification of dentin using collagen cross-linking followed by EWB exhibited a synergistic effect in improving the resin-dentin bond durability
Both synthetic and naturally derived crosslinkers have been found to exhibit significant effects in biomodification of dentine via their multiple interactions with the dentine matrix .
A stable matrix network or a durable hybrid layer in dentine bonding could be achieved , where the dentine collagen fibrils show improved biochemical and biomechanical properties and enzymatic biodegradation is reduced .
This aim of this review is to explore the current research related to  crosslinking agents used on dentine .