Effect of Acidic Beverages on Color Stability and Microhardness of Various Esthetic Restorative Materials: A Comparative Study.

AIM: The aim of this study was to assess the effect of acidic beverages on color stability and microhardness of various esthetic restorative materials.
MATERIALS AND METHODS: A total of 60 samples were included in the present study. Group I: Microhybrid composite resin, Group II: Nanoceramic, Group III: ORMOCER (Organically Modified Ceramics). 10 mm internal diameter and 5 mm depth of cylindrical aluminum mold of were utilized to prepare the samples. All the esthetic restorative samples were submerged for 10 min in 25 ml of acidic drink (Coca-Cola) each day up to 15 days. Vickers diamond intender was used to measure the microhardness of each sample. These values were calculated with baseline, 7th, and 15th days for final microhardness values.
RESULTS: The mean surface microhardness of 63.20 ± 0.46 was shown by Group III which was slightly more than that in Group II (60.08 ± 0.34) and Group I (58.10 ± 1.76). Analysis of covariance did not show any statistically significant difference between the groups. The samples in Group I showed the highest reduction in surface microhardness value after immersion into acidic drink, followed by Group II and Group III on 7th day and 15th day. A statistically significant difference (P < 0.001) was found on the 7th day.
CONCLUSION: The present study concludes that the Organically Modified Ceramics esthetic restorative material showed the finest behavior after being dipped in the acidic drink followed next by Nanoceramic and Microhybrid composite resin. Copyright:

INTRODUCTION

Increased demand by patients and clinicians for esthetic restorations coupled with the public's concern which has resulted in escalating use of resin composite materials worldwide in dentistry. Nanohybrid, the newer resin composite restorative material, is becoming popular as it combines physical, mechanical, and excellent esthetic properties. The average particle size of nanohybrid is less than that of microfilled composites resins. It has tooth-like translucency and is highly polishable, has good color stability, stain resistance, high wear strength, and can be used for anterior and posterior restorations.[1]

Sports and energy drinks “contain caffeine, taurine, vitamins, herbal supplements, and sugar or sweeteners and are marketed to improve energy, weight loss, stamina, athletic performance, and concentration”. Although numerous brands and items are accessible on the lookout, they by and large have comparative compositions.[2] The low pH of acidic food varieties and beverages supposedly incited articulated erosive wear in these materials. To be clinically successful, dental composites should be tough and have a serious level of wear obstruction in the oral cavity. They are uncovered either discontinuously or persistently to compound specialists found in saliva, food, and beverages, and such exposure can soften the resin matrix of the composite resins and cause filler constituents to leach out.[3]

As of late, bulk-fill resin-based composites with flowable and high-consistency types have been famous presently because of the simple application strategy not at all like the regular resin composites they can be embedded with 4 mm single layer. When attempting to advance the properties of the material, producers consolidated another high level composite filler advances by decreasing the filler substance to encourage further light transmission, expanding molecule sizes to improve the mechanical strength, exceptionally light-receptive photograph initiator systems.[4] So the current study was led to assess the impact of acidic drinks on color stability and microhardness of various esthetic restorative materials.

MATERIALS AND METHODS

The present in vitro study was conducted in the department of prosthodontics, SJM dental college and hospital, Chitradurga, Karnataka. Totally Sixty samples were prepared.

Group I: Microhybrid composite resin

Group II: Nanoceramic

Group III: ORMOCER (Organically Modified Ceramics).

Preparation of samples

Around 20 samples of every restorative material were readied utilizing a round and hollow aluminum form of 5 mm depth and 10 mm inner breadth. Vaseline was applied on the interior surface of each shape to encourage simple recuperation of the samples. The restorative materials were covered on the top and base surfaces with polyester matrix strips (Mylar Strips) and a flimsy inflexible glass slide to acquire a level and uniform polymerized surface with without any bubbles after curing. Finger pressure was applied on the glass slide to eliminate abundance material and polymerized for 40 s on each side utilizing a curing unit. One light polymerization mode was utilized for every material norm for 40 s. The light was put opposite to the sample surface, at distance of 1.5 mm. The upper surface of every sample was then cleaned with fine and superfine polishing disks to mimic clinical conditions. At that point, every one of the examples of different esthetic restorative materials was submerged in 25 ml of acidic beverage (Coca-Cola) for 10 min every day as long as 15 days.

Surface hardness test

The samples were smudged dry utilizing tissue paper and the baseline readings were obtained for surface hardness. Vickers diamond intender was utilized to gauge the microhardness of each sample when the inundation routine in acidic beverages. To record the reading, a force of 10 g for 15 s was applied on the uncovered surface of the sample following the convention testing by Yanikoğlu et al.[5] Three successive readings were made and their arithmetic mean was taken as baseline (Vickers hardness number [VHN1]). Toward the finish of the trial/inundation period, the normal microhardness of three readings (VHN2) of each sample was assessed in a way similar to that done for baseline surface hardness evaluation.

Statistical analysis

Data was analysed using SPSS software version 20.0. (SPSS Inc., Chicago, IL). One-way analysis of variance (ANOVA) was used to analyse the flexural strength between the groups. A P < 0.05 was considered as statistically significant.

RESULTS

Table 1 shows the mean surface microhardness values of three different esthetic restorative materials before the immersion into acidic beverages. The mean surface microhardness of 63.20 ± 0.46 was shown by Group III which was slightly more than that in Group II (60.08 ± 0.34) and Group I (58.10 ± 1.76). ANOVA did not show any statistically significant difference between the groups.

Table 1

Mean surface microhardness values of three different esthetic restorative materials before the immersion into acidic beverages

Esthetic restorative materials	Mean±SD	F	P
Group I: Microhybrid composite resin	58.10±1.76	26.361	0.842
Group II: Nanoceramic	60.08±0.34
Group III: ORMOCER	63.20±0.46

ORMOCER: Organically modified ceramics, SD: Standard deviation

Tables 2 and 3 depict the mean surface microhardness values of three different esthetic restorative materials at the 7th day and 15th day after the immersion into acidic beverages. The greater mean surface microhardness was found in Group III followed by Group II and Group I. A statistically significant difference was found between the groups on the 7th day.

Table 2

Mean surface microhardness values of three different esthetic restorative materials at 7th day after the immersion into acidic beverages

Esthetic restorative materials	Mean±SD	F	P
Group I: Microhybrid composite resin	49.80±0.83	24.720	0.001
Group II: Nanoceramic	51.18±0.65
Group III: ORMOCER	56.31±0.02

ORMOCER: Organically modified ceramics, SD: Standard deviation

Table 3

Mean surface microhardness values of three different esthetic restorative materials at 15th day after the immersion into acidic beverages

Esthetic restorative materials	Mean±SD	F	P
Group I: Microhybrid composite resin	48.14±0.42	23.686	0.07
Group II: Nanoceramic	50.36±0.28
Group III: ORMOCER	53.18±0.19

ORMOCER: Organically modified ceramics, SD: Standard deviation

The multiple comparisons among the mean surface microhardness values between the groups are as shown in Table 4. A statistically significant difference (P < 0.001) found in all groups except Group I versus Group II.

Table 4

Multiple comparisons of mean surface microhardness values using Tukey’s post hoc test

Groups	Compared with	Mean difference	Significant
Group I	Group II	−1.38	0.06
	Group III	−6.51	0.001
Group II	Group I	1.38	0.06
	Group III	−5.13	0.001
Group III	Group I	6.51	0.001
	Group II	5.13	0.001

DISCUSSION

In the oral cavity, restorative materials are presented to changes in temperature and corrosive base funds to be paid to food and drink utilization. To guarantee clinical life span, dental restorative materials ought to be satisfactorily impervious to such fluctuating conditions or be just negligibly influenced by them. Not withstanding, food and beverages are for the most part in contact with the tooth or reclamation surfaces for a brief span just before being washed away by salivation. In past studies on dental disintegration, trial substrates were inundated in acidic answers for delayed periods with no space for the purging part of salivation.[67]

Even though an incredible assortment of substances might be available at the oral climate, water, salivation, acids, bases, salts, and alcohols have been identified with the decrease of hardness, flexural strength, and flexural modulus properties.[8]

In addition, the biofilm collected over the restoration can deliver acidic substances that may suggest surface debasement, prompting the material's conditioning and surface roughening as to these acidic substances, the lactic, propionic, and acidic acids are generally found in the oral environment and they are used as storage solutions for screening accelerated hydrolysis phenomena of composite resins[9] and increment of hygroscopic extension of Bis-GMA-based materials. Chemical substances may affect more actively the organic matrix of composites, but the type, size, and concentration of fillers may also influence the material's resistance to degradation.[10]

In this study, we chose the Vickers microhardness test as it is genuinely a straightforward procedure, exceptionally normal, and dependable technique for getting the outcomes. Numerous studies[1112] regularly utilized as a indirect method to survey the level of polymerization fix and have thought about it as a marker for the level of polymerization of resin materials. The surface microhardness is related to the rigidity nature of the material and is viewed as a characteristic part of the resin's mechanical strength.

In a clinical environment, a material's diminishing of hardness may add to its crumbling. Under in vivo conditions, composite resin materials may be exposed either discontinuously or continually to chemical agents found in saliva, food, and beverages.[10] Consequently, in the short- or long-term, these conditions may have an alternate pernicious impact on the polymeric network, modifying its structure physically and chemically.

CONCLUSION

The present study concludes that the Organically Modified Ceramics esthetic restorative material showed the finest behavior after being dipped in the acidic drink followed next by Nanoceramic and Microhybrid composite resin.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.