In vitro effect of resin infiltrant on resistance of sound enamel surfaces in permanent teeth to demineralization

The erosive effect of pomegranate juice on enamel: An in vitro study

AIM

Dental erosion is a chemical-mechanical process that leads to the loss of dental hard tissues. This study aimed to investigate the effect of pomegranate juice on the enamel.

METHODS

Enamel blocks were randomly divided into three groups: deionized water, cola, and pomegranate juice. The blocks were immersed in the solutions four times a day for 14 days, and stored in artificial saliva for the remaining period. The surface hardness was measured on days 7 and 14. The surface structures of the demineralized blocks were observed via scanning electron microscopy (SEM), and the depth of demineralization was observed via confocal laser scanning microscopy (CLSM). The pH, calcium, and phosphorus levels of the three solutions were analyzed.

RESULTS

The microhardness values of the blocks in the pomegranate juice and cola groups decreased with the increase in the demineralization time. The blocks in the pomegranate juice group exhibited large fractures in the enamel column, whereas those in the cola group had pitted enamels with destruction of the interstitial enamel column. Compared with cola group, fluorescent penetration increased in pomegranate juice (P < 0.01). The pH of cola (2.32 ± 0.09) was lower than that of pomegranate juice (3.16 ± 0.16). Furthermore, the calcium content in pomegranate juice was significantly higher than that in cola (P < 0.01). Alternatively, the concentration of phosphorous in cola was significantly higher than that in pomegranate juice (P < 0.01).

CONCLUSION

These findings indicate that pomegranate juice can cause enamel demineralization with an erosive potential comparable to that of cola.

An in vitro evaluation of Icon resin infiltrant penetration into demineralized enamel lesions using an indirect staining technique with confocal laser scanning microscope analysis in dual fluorescence mode

Context

White spot lesion is the first clinical sign of a caries lesion and represents mineral loss from the enamel subsurface.

Aim

The aim of this study was to evaluate the penetration depth (PD) of Icon resin infiltrant into artificially demineralized enamel lesions using confocal laser scanning microscope (CLSM) analysis in dual fluorescence mode.

Settings and Designs

The design of the study was an in vitro study.

Materials and Methods

22 extracted human permanent maxillary central incisor teeth were collected, and enamel sections were obtained from the coronal middle third. All enamel specimens were exposed to demineralization and remineralization solutions for 14 days. On positive confirmation of enamel demineralization by scanning electron microscope analysis, 20 specimens were then subjected to Icon resin infiltration following manufacturer instructions. Specimens were processed with indirect staining technique using rhodamine B and sodium fluorescein dyes and examined under CLSM at ×10 magnification in dual fluorescence mode using ImageJ software to evaluate PD of resin infiltrant into demineralized enamel lesions.

Statistical Analysis Used

Obtained data were analyzed using an independent t-test. P ≤0.05 was considered statistically significant.

Results

The maximum depth of demineralized enamel lesion was 590 μm, and the mean depth was 290.78 ± 14.80 μm. The maximum depth of resin infiltrant penetration was 580 μm, and the mean depth was 279.08 ± 13.88 μm; P = 0.006. The percentage penetration of resin infiltrant was 95.99%.

Conclusion

Icon resin infiltrant was highly effective in its depth of penetration into demineralized enamel lesions. The use of indirect staining and CLSM analysis in dual fluorescence mode is more reliable and accurate technique to evaluate the PD of resin infiltrant.

Management of permanent incisors affected by Molar-Incisor-Hypomineralisation (MIH) using resin infiltration: a pilot study

PURPOSE

To compare the aesthetic improvement of Molar-Incisor-Hypomineralisation (MIH) opacities treated by applying Icon-Etch for three cycles with the opacities treated by Icon-Etch for once, in the course of resin infiltration technique.

METHODS

Thirty incisors were sorted based on the colour of the opacities and then distributed according to the number of Icon-Etch cycles using a randomisation table into the groups: (1) White/Creamy one cycle, (2) White/Creamy three cycles, (3) Yellow/Brown one cycle, (4) Yellow/Brown three cycles. The primary outcomes of applying the resin infiltration to the opacities were compared amongst groups according to the parents' satisfaction, the amount of coverage, and the colour matching with the surrounding sound enamel. The stability of the results after 3 months was evaluated using a spectrophotometer.

RESULTS

The colour of the opacity pre-treatment affected the outcomes significantly (p < 0.05), compared according to the method of application (p > 0.05) in terms of parents' satisfaction. Whilst the multiple applications for Icon-Etch cycles showed more coverage amount in White/Creamy opacities than the application ones (p < 0.05); in colour matching, there was no statistically significant difference between the two methods (p > 0.05). For yellow/brown opacities, some negative results occurred with the single Icon-Etch cycle.

CONCLUSION

In MIH opacities, it is possible to rely on the resin infiltration as a minimally invasive method to achieve acceptable results, especially with multiple Icon-Etch cycles applications in the white/creamy opacities. The colour stability has not been affected by either the colour of the opacity or the number of cycles.

Influence of resin infiltration pretreatment on the microleakage under orthodontic bracket (an in vitro study)

OBJECTIVES

In order to assess the changes in tooth orthodontic adhesive interface microleakage after applying a caries resin penetrated to the sound enamel tooth surface in different storage media.

MATERIALS AND METHODS

A total of 60 human maxillary first premolars (orthodontic extraction) were collected by random separation of the teeth into two equal groups. The control group was classified into three subgroups (n = 10) (control in deionized water, control in milk, and control in energy drink), while the experimental one (treated with ICON) was categorized into three subgroups (n = 10) (ICON in deionized water, ICON in milk, and ICON in energy drink) incubation phase lasted three weeks in total.

RESULTS

A one-way analysis of variance (ANOVA) yielded a significant difference between all experimental subgroups (ICON in deionized water, ICON in milk, and ICON in energy drink) and control subgroups (control in deionized water, control in milk, and control in energy drink). The control group in the energy drink subgroup had the highest mean microleakage value when compared to the other subgroups, whereas the resin-infiltrated group in deionized water had the lowest mean value. According to the results of the T-test, ICON pre-treatment tooth samples had significantly lower mean values of microleakage than non-ICON tooth samples.

CONCLUSIONS

The adhesive system (control group) revealed that a resin infiltrate on a sound enamel surface prior to orthodontic bracket bonding reduced bracket tooth interface microleakage in all examined samples. The ICON-infiltrated surface was discovered to provide a secondary preventive strategy against white spot lesion development by reducing microleakage under brackets.

Hairy roots: An untapped potential for production of plant products

While plants are an abundant source of valuable natural products, it is often challenging to produce those products for commercial application. Often organic synthesis is too expensive for a viable commercial product and the biosynthetic pathways are often so complex that transferring them to a microorganism is not trivial or feasible. For plants not suited to agricultural production of natural products, hairy root cultures offer an attractive option for a production platform which offers genetic and biochemical stability, fast growth, and a hormone free culture media. Advances in metabolic engineering and synthetic biology tools to engineer hairy roots along with bioreactor technology is to a point where commercial application of the technology will soon be realized. We discuss different applications of hairy roots. We also use a case study of the advancements in understanding of the terpenoid indole alkaloid pathway in Catharanthus roseus hairy roots to illustrate the advancements and challenges in pathway discovery and in pathway engineering.

Evaluation of Infiltrant Application in the Course of Root Cementum Caries with Different Methods of Surface Preparation—An In Vitro Study

The aim of this study is to evaluate the depth of penetration of an experimental preparation with the characteristics of a dental infiltrant into the decalcified root cementum tissue and observation of the root cementum tissue subjected to a single and repeated twice hydrochloric acid etching process. The study material consisted of 20 human teeth (the study group—12 demineralised teeth, the control group—8 teeth). A commercially available Icon preparation and an experimental preparation were used for the study with addition 2% of YF3 (yttrium trifluoride) added as an indicator to facilitate microscopic observation. Each tooth was divided into two zones, blue (Icon) and red (experimental preparation). The teeth were divided into two subgroups—in the first subgroup, the etching preparation was applied once, in the second subgroup twice, and at the end the teeth were infiltrated with the experimental preparation and the Icon preparation. The study of tooth longitudinal section morphology and chemical composition was performed with the use of a Hitachi S-3400N scanning electron microscope. Microscopic observations show that the applied YF3 tracer in most cases agglomerates and remains in the form of conglomerates on the surface of the root cementum. Single particles of YF3 are visible, penetrating through the cementum tissues into the root dentine structure. The degree of tissue infiltration with the resin (depth of penetration into decalcified tissues) is visible at a depth of approx. 80–120 μm. In the test group subjected to a single etching process, good penetration of both resins was noticeable, however, excessive erosion of the root surface was evident in several of the specimens—indicating that damage occurred as a result of the etching process. In the test group subjected to two etching processes, excessive erosion of the cementum is visible in each deposit.