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. 2010 Dec;89(12):1499-504.
doi: 10.1177/0022034510385240. Epub 2010 Oct 12.

Ethanol wet-bonding challenges current anti-degradation strategy

F T Sadek  1 , R R Braga, A Muench, Y Liu, D H Pashley, F R Tay
Affiliations

Ethanol wet-bonding challenges current anti-degradation strategy

F T Sadek et al. J Dent Res. 2010 Dec.

Abstract

The long-term effectiveness of chlorhexidine as a matrix metalloproteinase (MMP) inhibitor may be compromised when water is incompletely removed during dentin bonding. This study challenged this anti-bond degradation strategy by testing the null hypothesis that wet-bonding with water or ethanol has no effect on the effectiveness of chlorhexidine in preventing hybrid layer degradation over an 18-month period. Acid-etched dentin was bonded under pulpal pressure simulation with Scotchbond MP and Single Bond 2, with water wet-bonding or with a hydrophobic adhesive with ethanol wet-bonding, with or without pre-treatment with chlorhexidine diacetate (CHD). Resin-dentin beams were prepared for bond strength and TEM evaluation after 24 hrs and after aging in artificial saliva for 9 and 18 mos. Bonds made to ethanol-saturated dentin did not change over time with preservation of hybrid layer integrity. Bonds made to CHD pre-treated acid-etched dentin with commercial adhesives with water wet-bonding were preserved after 9 mos but not after 18 mos, with severe hybrid layer degradation. The results led to rejection of the null hypothesis and highlight the concept of biomimetic water replacement from the collagen intrafibrillar compartments as the ultimate goal in extending the longevity of resin-dentin bonds.

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Figures

Figure 1.
Figure 1.
Representative TEM images of 18-month-aged hybrid layers created by ethanol wet-bonding in the absence/presence of chlorhexidine diacetate (CHD) and coaxing the ethanol-saturated matrix with an experimental hydrophobic adhesive. Although voids were evident within the hybrid layers, the collagen matrix within did not degrade, regardless of whether CHD was included in the absolute ethanol used for the final rinse. C, composite; A, adhesive. Between open arrows, hybrid layer. D, dentin; T, dentinal tubule. (A) Low magnification of the resin-dentin interface in the subgroup without CHD. (B) High magnification of (A) showing wide interfibrillar spaces (ca. 50 nm; arrow) within the hybrid layer that were probably caused by shrinkage of interfibrillar proteoglycans (Mazzoni et al., 2008) in absolute ethanol. This provided a higher resin/collagen ratio within the hybrid layer. Open arrowhead: voids within the hybrid layer. (C) Low magnification of the resin-dentin interface in the CHD subgroup. (D) High magnification of (C). Similar voids were present within the hybrid layer (open arrowheads).
Figure 2.
Figure 2.
Representative TEM images of 18-month-aged hybrid layers created by water wet-bonding in the absence/presence of CHD and bonding with Scotchbond Multi-Purpose. C, composite; A, adhesive. Between open arrows: hybrid layer. D, dentin; T, dentinal tubule. (A) An example of partial degradation (arrows) of the hybrid layer in the subgroup without CHD. Regions with through-and-through disappearance of the hybrid layer from the composite side to the dentin side (asterisk) were supported by the laboratory-infiltrated epoxy resin. (B) High magnification of the region indicated by arrows in (A) showed loss of fibrillar integrity in the degraded hybrid layer. Pointers: lateral branches of the dentinal tubules. (C) High magnification of the through-and-through region in (A). That space contained denatured collagen components (open arrowhead) and possible microbial invasion (pointers). Arrow: polyalkenoic acid copolymer component of the adhesive. (D) An example of an intact hybrid layer that was sometimes seen in the CHD subgroup bonded by the same adhesive. Arrow: polyalkenoic acid copolymer.
Figure 3.
Figure 3.
Representative TEM images of 18-month-aged hybrid layers created by water wet-bonding in the absence/presence of CHD and bonding with Single Bond 2. C, composite; A, adhesive. Between open arrows: hybrid layer. D, dentin; T, dentinal tubule. (A) An example of a hybrid layer with initial signs of collagen degradation (open arrowheads) in the subgroup without CHD. (B) An example of a hybrid layer with more severe degradation (asterisk) with possible microbial contamination (pointer) in the subgroup without CHD. (C) High magnification of a region indicated by a black arrow within the degraded hybrid layer in (B) (subgroup without CHD), showing the breakdown of intact collagen fibrils into microfibrillar strands (arrow). (D) An example of an intact hybrid layer that was seen in the CHD subgroup bonded by the same adhesive.
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References

    1. Becker TD, Agee KA, Joyce AP, Rueggeberg FA, Borke JL, Waller JL, et al. (2007). Infiltration/evaporation-induced shrinkage of demineralized dentin by solvated model adhesives. J Biomed Mater Res B Appl Biomater 80:156-165 - PubMed
    1. Blackburn RS, Harvey A, Kettle LL, Manian AP, Payne JD, Russell SJ. (2007). Sorption of chlorhexidine on cellulose: mechanism of binding and molecular recognition. J Phys Chem B 111:8775-8784 - PubMed
    1. Breschi L, Cammelli F, Visintini E, Mazzoni A, Vita F, Carrilho M, et al. (2009). Influence of chlorhexidine concentration on the durability of etch-and-rinse dentin bonds: a 12-month in vitro study. J Adhes Dent 11:191-198 - PMC - PubMed
    1. Cameron IL, Short NJ, Fullerton GD. (2007). Verification of simple hydration/dehydration methods to characterize multiple water compartments on tendon type 1 collagen. Cell Biol Int 31:531-539 - PubMed
    1. Carrilho MR, Carvalho RM, de Goes MF, di Hipolito V, Geraldeli S, Tay FR, et al. (2007a). Chlorhexidine preserves dentin bond in vitro. J Dent Res 86:90-94 - PMC - PubMed

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