In Vitro Comparative Evaluation of Change in Mass, pH and Fluoride Release of Cention-N and Glass–Ionomer Cement

INTRODUCTION

Primary tooth restoration materials differ in terms of their biocompatibility, longevity, and safety. Recent developments have brought resinous and polyalkenoate-based materials as alternatives to amalgam restorations.^1,2 It is essential to keep primary teeth through younger ages in order to preserve natural functions and space.¹ The mechanical qualities of the repair are affected by texture, dehydration, early moisture sensitivity, extended setting reaction times, and clinical failure are only a few of the disadvantages associated with conventional GICs. Many GIC modifications, including high-viscosity glass ionomers, resin-modified glass ionomer cements (RMGICs), and polyacid-modified composite resins (PMCRs) have been created to get around these problems.³

A tooth-colored composite material called Cention-N (CN) uses alkaline fillers that release ions that neutralize acids. It is radiopaque, self-curing, and comes in tooth shade A2. Extra light curing is optional. Blue light with a wavelength of roughly 400–500 nm is used for optional light curing. 78.4% of Cention-N’s weight is made up of inorganic filler, while 24.6% is alkaline glass counts. This results in significant fluoride ion release levels that are similar to those of conventional glass ionomer cements. Furthermore, the alkaline glass releases calcium and hydroxide ions, which stop demineralization even further. When comparing Cention-N to ordinary GIC, the long-term release of calcium and fluoride ions in an acidic environment is greater.⁴ Therefore, in type IX GIC and CN, a comparative assessment of the change in mass, pH, and fluoride release was taken into consideration in this investigation.

MATERIALS AND METHODS

Using Type IX Glass Ionomer cement (control group A) and CN (experimental group B), circular mold samples with 10 mm diameter and 3 mm thickness were created. The cement is blended in accordance with the manufacturer’s recommendations. A total of 200 molds were made, each including 100 type IX GIC and 100 CN molds. To prevent early moisture contamination or desiccation, the mixed restorative materials were inserted under consistent pressure into Teflon molds, with mylar strips on both sides of the mold. Following setting, the pellets were taken out of the mold, and any extra material was cut off with a Schwann-Morton blade. Varnish was then applied, and the pellets were split into two equal groups.

RESULTS

The change in mass and pH in Type IX GIC and CN were observed as either increase or decrease from its initial recorded values and the increased values were expressed as (+) and decrease as (–). The recorded values were tabulated and subjected to statistical analysis using paired t-test.

DISCUSSION

Artificial saliva, adjusted to a critical pH of 5.5, was used as the storage medium. If the solution is higher than the critical pH, then it is supersaturated, and more mineral tends to precipitate out, whereas if the solution is lower than the critical pH it is unsaturated and the mineral will continue to precipitate out until the solution reaches saturation, which can lead to tooth demineralization. Type IX GIC showed increased mass in comparison to CN after storage in artificial saliva for 1 week and 1 month. This could be a sign of continuing “maturation” phase of GIC which occurs over time after initial setting due to slow reaction of aluminum ions.⁵

Type IX GIC showed an increase in mass in comparison to CN after storage in the artificial saliva for 1 week and 1 month. This could be a sign that the GIC is continuing to “mature” after initial setting.⁶ The slow reaction of aluminum ions is responsible for this. Researchers have found that an increase in GIC mass when aqueously dissolved in solutions of water or lactic acid is associated with water sorption.^7,8 This would help to prevent the restorable material from shrinking and crazing, which would also increase its mass. The change of mass observed in this study was consistent with the findings found in the literature review. The paucity of review of variation of mass of CN could not be attributed to any cause. It is unclear what role water plays in setting of CN. In the present study, CN has shown a change in pH toward alkalinity.

The initial exposure of lactic acids and metal lactates in artificial saliva creates a buffer solution and leads to increase in pH, and results in net gain in mass by the cement as it takes up the water for maturation. A study evaluated the interactions of glass–ionomer cements used in atraumatic restorative treatment (ART-GICs) with an aqueous lactic acid solution. Atraumatic restorative treatment materials increase the pH of the lactic acid solution.^9–14

The release of F- from dental materials is governed by intrinsic factors, such as composition, powder/liquid ratio, mixing time, temperature, specimen geometry, permeability, surface treatment and finishing, and extrinsic factors, such as storage medium, experimental design, and analytical methods.¹⁵

The release of fluoride ions is the notable characteristics of GICs. The presence of fluoride increases translucency, strength and improves handling properties. However, it is maximum in the first few days and decreases rapidly to a lower level over weeks, and maintains a low level over months. Glass–ionomer cement can be “recharged” with fluoride, resulting in a subsequent short-term boost in release. In the present study, CN has shown a significant increase in fluoride release when compared with GIC at the end of 1 week and 1 month.¹⁶

In a research study aimed at assessing and contrasting the fluoride ion release of Cention-N (self-cure and light-cure) and conventional GIC at various pH levels and time intervals, it was observed that the Cention-N (self-cure) demonstrated the highest potential for fluoride ion release in an acidic environment, while GIC exhibited this potential in a neutral environment. Fluoride ion release was higher in acidic pH compared with neutral pH for both Cention-N and GIC. Over time, the fluoride ion release decreased in both acidic and neutral pH for all groups, except for GIC in an acidic environment, where it remained constant. Additionally, the release gradually increased over time and contributed to the effects on the demineralization/remineralization interface.⁶

CONCLUSION

Cention-N has shown variation in pH toward alkalinity and increased fluoride release compared with Type IX GIC favors remineralization. The increase in mass was observed in Type IX GIC when compared with CN. Marginal increase in mass would result in water sorption and prevent restorative material from shrinkage and crazing. Cention-N can be a better restorative properties than Type IX GIC in primary dentition.

ORCID

Vidhya Vijayan https://orcid.org/0000-0002-7410-2398

George Babu https://orcid.org/0000-0002-5474-1299

REFERENCES

1. Duangthip D, Chen KJ, Gao SS, et al. Managing early childhood caries with atraumatic restorative treatment and topical silver and fluoride agents. Int J Environ Res Public Health 2017;14(10):1204. DOI: 10.3390/ijerph14101204.

2. Menezes-Silva R, Cabral RN, Pascotto RC, et al. Mechanical and optical properties of conventional restorative glass-ionomer cements-a systematic review. J Appl Oral Sci 2019;27. DOI: 10.1590/1678-7757-2018-0357.

3. Savas S, Colgecen O, Yasa B, et al. Color stability, roughness, and water sorption/solubility of glass ionomer–based restorative materials. Niger J Clin Prac 2019; 22(6):824. DOI: 10.4103/njcp.njcp_592_18.

4. Mazumdar P, Das A, Das UK. Comparative evaluation of microleakage of three different direct restorative materials (silver amalgam, glass ionomer cement, Cention N), in Class II restorations using stereomicroscope: An in vitro study. Indian J Dent Res 2019;30(2):277. DOI: 10.4103/ijdr.IJDR_481_17.

5. Dawes C. What is the critical pH and why does a tooth dissolve in acid? J Can Dent Assoc 2003;69(11):722–725. PMID: 14653937.

6. Kaur M, Mann NS, Jhamb A, et al. A comparative evaluation of compressive strength of Cention N with glass ionomer cement: An in-vitro study. Int J Appl Dent Sci 2019;5(1):5–9. DOI: 214031229.

7. Nicholson JW, Czarnecka B, Limanowska-Shaw H. A preliminary study of the effect of glass-ionomer and related dental cements on the pH of lactic acid storage solutions. Biomater Res 1999;20(2):155–158. DOI: 10.1016/s0142-9612(98)00153-7.

8. Czarnecka B, Nicholson JW. Ion release by resin-modified glass-ionomer cements into water and lactic acid solutions. J Dent 2006;34(8):539–543. DOI: 10.1016/j.jdent.2005.08.007.

9. Abduo J, Swain M. Self‐reparability of glass‐ionomer cements: An in vitro investigation. Eur J Oral Sci 2011;119(2):187–191. DOI: 10.1111/j.1600-0722.2011.00810.x.

10. Sidhu SK. Glass‐ionomer cements restorative materials: A sticky subject? Aust Dent J 2011;56:23–30. DOI: 10.1111/j.1834-7819.2010.01293.x.

11. Czarnecka B, Limanowska-Shaw H, Nicholson JW. Buffering and ion-release by a glass-ionomer cement under near-neutral and acidic conditions. Biomat Res 2002;23(13):2783–2788.

12. Crisp S, Lewis BG, Wilson AD. Glass ionomer cements: Chemistry of erosion. J Dent Res. 1976;55(6):1032–1041. DOI: 10.1177/00220345760550060501.

13. Nicholson JW, Millar BJ, Czarnecka B, et al. Storage of polyacid-modified resin composites (“compomers”) in lactic acid solution. Dent Mater J 1999;15(6):413–416. DOI: 10.1016/s0109-5641(99)00067-6.

14. Wang L, Cefaly DF, Santos JL, et al. In vitro interactions between lactic acid solution and art glass-ionomer cements. J Appl Oral Sci 2009;17(4):274–279. DOI: 10.1590/s1678-77572009000400002.

15. Markovic DL, Petrovic BB, Peric TO. Fluoride content and recharge ability of five glass ionomer dental materials. BMC Oral Health 2008;8(1):21. DOI: 10.1186/1472-6831-8-21

16. Tyas MJ, Burrow MF. Adhesive restorative materials: A review. Aust Dent J 2004;49(3):112–121, 112–154. DOI: 10.1111/j.1834-7819.2004.tb00059.x.