Roughness and Microhardness of Demineralized Enamel Treated with Resinous Infiltrants and Subjected to an Acid Challenge: An in vitro Study

Abstract

Background: Resinous infiltrating has proven effective in arresting incipient caries lesions. Objective: This study aimed to assess the penetration depth of an experimental resin-infiltrant (75% - TEGDMA, 25% - Bis-EMA, 1% - EDAB, 0.5% camphorquinone), compare it with commercial infiltrant Icon®, and analyze the surface-roughness and microhardness of the resin-materials infiltrated into tooth specimens, before and after pH cycling. Methods: To assess penetration depth, sound third molar specimens were submitted to ten de-remineralization cycles for incipient carious lesion induction and were then randomly divided into 2 groups (n=3): (I) Experimental Infiltrant (EI) and (II) Commercial Infiltrant Icon (CI). After resin infiltration into specimens, qualitative Confocal Fluorescence Microscopy images were captured. For roughness and microhardness assessment, new specimens were demineralized, then randomly divided into two groups (n=20): (I) Experimental Infiltrant (EI) and (II) Commercial Infiltrant Icon (CI) and submitted to roughness and microhardness readouts at the following time-intervals: (T1) sound tooth, (T2) white-spot caries lesion, (T3) resin material that infiltrated, and (T4) resin material that infiltrated and was exposed to pH-cycling. In statistical analyses, generalized linear models of repeated measures in time were applied, with a significance level of 5%. Results: The experimental infiltrant penetrated the carious lesion and exhibited lower roughness values after its application, even after pH cycling, similar to the CI. The microhardness value of the EI group was significantly lower in the last three-time intervals evaluated compared to CI. Conclusion: Experimental resin infiltrant was efficient in penetrating white spot lesions and reducing surface roughness; however, it did not increase surface microhardness.

A Comparative In Vitro Physicochemical Analysis of Resin Infiltrants Doped With Bioactive Glasses

“…The specimen surface on the side subjected to artificial saliva and pH cycling challenges had a higher surface roughness than the other surfaces in the representative SEM pictures of this investigation. The pictures, on the other hand, agreed with the numerical findings, which showed an increase in roughness [ 46 ]. The RIF group exhibited the highest microhardness values along with more resistance in terms of surface roughness, following artificial saliva and pH cycling challenges, and showed higher surface roughness values than others; it proves that the formation of apatite layer is more on RIF than enhances its microhardness.…”

Evaluation of experimental resin infiltrant containing nanohydroxyapatite on color stability and microhardness in demineralized enamel

“…This can be explained by their composition, which includes a higher constitution in the monomeric base such as TEGDMA that incorporates pigments, similar to Icon, as described by Alqahtani and Ceci [24,28]. The formulation of the experimental in ltrants without the addition of nanoparticles is also supported by other studies, such as Cerqueira and Pedreira [34,14], where the depth of penetration, sorption and solubility results, cohesive strength, and degree of conversion were found to be similar or superior to Icon.…”

Correlation of enamel surface roughness, hardness, and demineralization following the use of orthodontic brackets

“…(48) Enamel surface roughness and demineralization are primarily related to and initiated by plaque and bacterial accumulation. (21,44) This could explain the non-signi cant correlation between enamel surface roughness and demineralization observed in this study, whose data were retrieved from in vitro studies (without a dental bio lm model). Moreover, bacterial adherence is in uenced by several factors other than surface roughness, including surface electrostatic interactions, hydrophobic ion bonding, van der Waals forces, and host-related factors including saliva characteristics and oral hygiene.…”

“…The extent of surface roughness is associated with higher bacterial adherence and plaque accumulation, facilitating acid production and demineralization. (20)(21)(22)(23)44,45) However, studies evaluating the correlation of the enamel surface roughness attribution to its demineralization depth following orthodontic bracket use are limited. We found a weak positive correlation between enamel surface roughness and demineralization depth; however, this correlation was statistically insigni cant.…”