Resin Penetration in Artificial Enamel Carious Lesions after Using Sodium Hypochlorite as a Deproteinization Agent

Abstract

Objectives: To study the degree of penetration of an adhesive resin in artificial enamel carious lesions after using sodium hypochlorite as deproteinization agent. Study design: Twenty included human third-molars, extracted for surgical indication, were used. Artificial lesions were created in the buccal and lingual sides of each specimen through a cycle of demineralization-remineralization. Samples were then incubated in human saliva for 7 days at 37 ° C. After surface cleaning, lesions and the peripheral sound enamel were etched with 37% orthophosphoric acid for 20 seconds. One lesion of each specimen was treated with 5.25% sodium hypochlorite (NaOCl) for one minute. The other lesion of each specimen was used as a control. Experimental and control lesions were sealed with a fluid resin marked with Rhodamine B. Lesions were sectioned for microscopic observation by epifluorescence and polarized light. The images obtained were analyzed morphometrically. The micrometer measurements were made with ImageJ ® software. The level of significance was assessed at p<0.05. Results: The average sealant depth penetration in the control group was 94.9 ± 28.6 ?m versus 122.8 ± 25.3 μm in the experimental group. This represents Δ 20.1% significantly greater penetration when using sodium hypochlorite (p<0.001). Conclusion: The results demonstrated a significant penetration of the sealing resin when the conventional technique is complemented with the application of 5.25% sodium hypochlorite for one minute in artificial enamel carious lesions.

Effect of enamel-surface modifications on shear bond strength using different adhesive materials

“…The enamel surface can be deproteinized with NaClO before bonding to increase the penetration of the adhesive into the enamel and further improve the bond strength. Thus, prior to acid etching, 5.25% NaClO is applied onto the enamel surface for 1 min to improve the etching property [ 11 , 12 ]. The pH of NaClO is similar to that of calcium hydroxide, which reacts with OH– to form NaOH and HClO.…”

“…Meanwhile, sodium hypochlorite (NaClO) solution provides specific properties such as disinfection and cleaning of root canals from impurities and organic substances. Previous studies have shown that pretreatment of enamel surface with NaOCl can increase the degree of penetration of adhesives into the enamel [ 11 , 12 ]. Owing to the deproteinization of the enamel surface by NaClO, suitable acid etching is required to achieve better bond strength between the bracket and enamel [ 13 , 14 ].…”

Effectiveness of sodium hypochlorite treatment on the bonding of four adhesive systems to fluorotic enamel

“…And beyond that, our study showed that when the enamel was treated with or without 5.25% NaOCl, no significant difference was observed in PD of CSB and PBN except for SB2 and SBU. However, the previous findings indicated that using 5.25% NaOCl for 60 s can improve the PD of the sealing resin significantly 27) . It revealed that the application of 5.25% NaOCl got rid of protein from the surface and increased porosity 24) .…”

“…Previous research indicated there was a remarkably greater protein content by weight in fluorotic enamel and inter-rod areas contained more organic material than enamel rods 25,26) . In addition, NaOCl not only removed the excess protein content from the enamel surface but also got rid of salivary proteins and organic material from saliva which was adsorbed in the surface of the teeth and might disturb acid etching and penetration of the resin 14,27) . Some studies also revealed that the application of NaOCl in 60 s increased the type 1-2 etching pattern of enamel 13,25,28) .…”

Effect of Sodium Hypochlorite (NaOCl) for Pretreatment of Early Demineralized Enamel Lesions in Enhancing the Remineralization Capacity of Self-assembling Peptide (In-vitro Study)

“…17,18 On the other side, the application of sodium hypochlorite after acid etching during the process of surface pretreatment has been discussed in literature proving its effect in enhancing the shear bond strength values, increasing the penetration and retention of adhesive resins by 20.1% compared to the conventional way of only acid etch the enamel surface, and affects the surface roughness of enamel surface with the minimum percentage of surface loss. [19][20][21][22] Upon all these findings regarding using sodium hypochlorite as an enamel surface pretreatment and self-assembling peptide remineralization capabilities, it was found thought-provoking to study the effect of applying sodium hypochlorite as a deproteinizing agent after acid etching of demineralized sound enamel structure with the aim of minimizing loss of surface enamel, exposure of more reactive enamel, and creation of porosities that may allow for more rapid uptake of remineralizing solution as assessed by surface microhardness (SMH) testing.…”