ORIGINAL RESEARCH

https://doi.org/10.5005/jp-journals-10077-3262
Journal of South Asian Association of Pediatric Dentistry
Volume 6 | Issue 2 | Year 2023

A Comparative Study to evaluate the Clinical Efficacy of a Novel Alkasite-based Material (Cention N), Resin-modified Glass Ionomer Cement, and Composite Resin for Restoration of Class II Cavities in Primary Molars: A Randomized Control Trial

Diksha Bhat¹, Monika Gupta², Inder K Pandit³, Neeraj Gugnani⁴

¹Department of Pediatric and Preventive Dentistry, I.T.S-CDSR Murad Nagar, Ghaziabad, Uttar Pradesh, India

^2-4Department of Pediatric and Preventive Dentistry, J.N. Kapoor DAV (C) Dental College, Yamunanagar, Haryana, India

Corresponding Author: Diksha Bhat, Department of Pediatric and Preventive Dentistry, I.T.S-CDSR Murad Nagar, Ghaziabad, Uttar Pradesh, India, Phone: +91 9906019678, e-mail: dikshabhat94@rediffmail.com

Received on: 17 March 2023; Accepted on: 08 May 2023; Published on: 23 August 2023

ABSTRACT

Aim: To evaluate and compare the clinical success of an alkasite-based restorative material (Cention N), resin-modified glass ionomer cement (RMGIC) (3M ESPE Vitremer), and composite resin (Ceram X) when used as a restorative material in class II cavities in primary molars.

Materials and methods: Around 45 primary molars were randomly divided into three equal groups—group I—Cention N, group II—RMGIC (3M ESPE Vitremer), and group III—composite (Ceram X) and restored with restorative materials, respectively. At 1-week, 1, and 4-month recall intervals the restorations were evaluated using FDI—criteria. Internal root resorption and pulp vitality were also evaluated at 4-month recall intervals.

Results: The data were analyzed using the Chi-squared test. Cention N proved to exhibit the best performance followed by RMGIC and composite resin. After 4 months of recall intervals, the statistical analysis showed a significant difference in terms of marginal/surface staining (p = 0.004), material fracture/retention (p = 0.001), marginal adaptation (p = 0.027), and postoperative sensitivity (p = 0.046), however, a nonsignificant difference was observed in terms of recurrence of caries (p = 0.407), internal root resorption (p = 0.207), and pulp vitality (p = 0.207) in all the three groups.

Conclusion: Cention N exhibited the highest success rate when compared to RMGIC and composite resin.

How to cite this article: Bhat D, Gupta M, Pandit IK, et al. A Comparative Study to evaluate the Clinical Efficacy of a Novel Alkasite-based Material (Cention N), Resin-modified Glass Ionomer Cement, and Composite Resin for Restoration of Class II Cavities in Primary Molars: A Randomized Control Trial. J South Asian Assoc Pediatr Dent 2023;6(1):56-61.

Source of support: Nil

Conflict of interest: None

Keywords: Class II restorations, Composite resin, Dental caries, Primary molar.

INTRODUCTION

Dental caries is an irreversible microbial disease of the calcified tissues of the teeth, characterized by demineralization of the inorganic portion, and destruction of the organic substance of the tooth, which often leads to cavitations.¹

According to World Health Organization, 60–90% of schoolchildren suffer from dental caries.² A study was conducted by Dimitrov et al., 2017 which reported that the percentage of children without occlusal caries on a primary molar is 60%, while those without approximal caries is barely 18%.³ The primary modality to treat a cavitated lesion is to excavate the carious lesion and restore the cavity with a suitable restorative material.

Previously, amalgam was employed as a restorative material for a variety of reasons, including affordability, low technique sensitivity, self-sealing, and longevity, which makes it a suitable material. However, amalgam restoration is unesthetic and in order to obtain enough resistance and retention, it is often necessary to remove sound tooth structure, but in the primary dentition, retention is limited due to the thin enamel and dentine, shallow pits and fissures, small occlusal tables, and occlusal oriented enamel rods.⁴

Composite resins have been the mainstay for restoration, ever since they came into existence in the 1960s, but their technique sensitivity, polymerization shrinkage leading to marginal microleakage, postoperative sensitivity, and secondary caries remain a matter of concern.⁵ Furthermore, composite restorations require effective moisture management, which is challenging to achieve in children.⁶

Another most commonly used restorative material for primary teeth includes GIC. They have several benefits, including chemical adherence to the tooth, allowing for little destruction of healthy dental tissue, a continuous fluoride release with possible cariostatic action, high biocompatibility, and a tooth-like color. Literature reports the success rate of conventional GIC in class II to be 81%⁷ but a systemic review conducted by Chadwick and Evans showed that failure rates varied from 6.6 to 60%.⁸ The popularity of GICs is limited by their slow setting action, early dehydration, susceptibility to moisture contamination, low fracture toughness, and poor wear resistance, especially in the load-bearing area such as in class II cavities.⁹

In the 1990s RMGIC was launched as a new restorative material. This material provides superior fracture toughness, moisture resistance, and a longer working period than traditional GIC; still, their major limitation is that their resistance to wear has not been improved much.¹⁰

Therefore, to overcome these limitations which include the intrinsic gray color of amalgam and toxicity associated with its mercuric content, while composite is a time-consuming and technique-sensitive material, and low flexural strength associated with GICs, dentists have long sought an ideal material for restoration that has strength like amalgam, esthetics like composite and is technically insensitive like GIC.

Cention N has recently been introduced in dentistry. Inventors declare that it combines the greatest qualities of amalgam, composite, and GIC.¹¹

It is an “alkasite” restorative material, essentially a subgroup of the composite material class like compomer or ormocer.¹² This new category makes use of alkaline filler that promotes the release of hydroxide ions during acid attacks to regulate the pH and prevent demineralization. Fluoride and calcium ions are released in high quantities, which aid in the remineralization of dental enamel.¹³

This material has the potential to deliver a high-quality, predictable restoration at a lower cost and in a shorter amount of time.⁵

This study introduces the new restorative material Cention N as the most efficient restorative in terms of clinical pediatric dentistry as it is a tooth-colored and restorative filling material for bulk placement in retentive preparations.

Therefore, the objective of the study was to evaluate and compare the clinical success using FDI criteria and to assess internal root resorption and pulp vitality using intraoral periapical radiographs and electric pulp testing among teeth restored with Cention N, RMGIC, and composite resin. According to the null hypothesis, there is no difference in terms of clinical efficacy between these three restorative materials when used in class II cavities in primary molars.

MATERIALS AND METHODS

Study Design

The present study is a three-group randomized controlled assessor-blinded study with a 1:1:1 allocation ratio. The three interventions included—alkasite based restorative material (Cention N), RMGIC (3M ESPE Vitremer), and composite resin (Ceram X).

Ethical Approval

The protocol was written as per spirit guidelines.¹⁴ The Institutional Ethical Committee of JN Kapoor DAV (C) Dental College Yamunanagar, Haryana and afterward the Review Board of Pt. BD Sharma University of Health Sciences, Rohtak, provided ethical permission for the study. The study followed good clinical practice principles.¹⁵

Participants

A sample of children aged 4–9 years old was chosen at random from the outpatient department of Pediatric and Preventive Dentistry, J.N. Kapoor DAV(C) Dental college Yamunanagar, Haryana Dental College and Hospital, J.N. Kapoor DAV(C) Dental college Yamunanagar, Haryana. Initially, the patients were screened for cavitated lesions in proximal areas of primary molars. Only those patients who fulfilled the inclusion criteria that are proximal caries with or without occlusion involvement in primary molars which is detected by using a radiograph, presence of at least two-thirds of the root length, teeth that were restorable, and teeth with intact proximal surfaces of the adjoining tooth were selected. However, teeth with extensive carious lesions involving pulp, with more than one-third root resorption or having any sign/symptoms depicting pulpal or periapical pathology were excluded.

Following the screening and the selection process, parents of children selected for the study were explained about the study as well as treatment choices and the risks associated if any. After discussing the procedure, and its related minor safety aspects involved, informed consent was taken in writing as well, from the parents of their children who were included in the study.

Randomization

Randomization was carried out for children included in the study after recording the baseline data. The block randomization method is used to randomize participants into groups that result in equal sample sizes. Research randomizer software (www.randomizer.org) was used for the random sequence generation of three groups. The allocation concealment was accomplished by using sealed envelopes prepared by an independent individual prior to the commencement of the trial. The sequence generation table was likewise sealed and protected till the end of the trial. Independent personnel, who were not engaged in the sequence generation, assigned the subjects to distinct treatment groups.

Sample Size

As per power analysis, accepting the type I error of 5% and taking the power of study at 80% (accepted type II error of 20%) the sample size required was 44 in each group. However, pertaining to the time constraints, a convenient sample of 15 patients per group was included.¹⁶

A total of 45 primary molars with class II lesions were randomly divided into three groups (Flowchart 1):

Flowchart 1: Flowchart of materials and methodology

Group I (n = 15): Alkasite-based material (Cention N).
Group II (n = 15): RMGIC (3M ESPC Vitremer).
Group III (n = 15): Composite resin (Ceram X).

Procedure

Isolating the tooth with the help of a rubber dam is done. It prevents contamination of the working field from saliva, blood, and sulcular fluids.

After that, the class II cavity was prepared in the first or second primary molar on either the maxilla or the mandible using the following technique—cavity should have a smaller depth and a narrower occlusal form. The proximal extensions should be positioned where they may be viewed, probed, and polished. Internal line angles should be rounded. Retention grooves should also be present in the gingival wall and axiofacial and axiolingual proximal line angles. Proximal margins should be beveled, but not occlusal edges.

In class II restorations the Universal (Tofflemire) matrix system is used. The matrix’s main rationale is to recreate anatomical proximal contours and contact regions. In order to be appropriately positioned, a matrix must be firm against the preexisting tooth structure.

To restore the teeth, the appropriate restorative materials were used and the manufacturer’s instructions were followed for treating the materials:

Group I (Cention N): The cavity was rinsed thoroughly and dried using a blotting paper strip. The bonding agent (Tetric N-Bond Ivoclar Vivadent) was applied and light cured for 20 seconds. Then the cavity was restored with Cention N and light cured for 60 seconds. The final curing was done for 60 seconds.
Group II (RMGIC-Vitremer): After applying the primer for 30 seconds, it was light-cured for 20 seconds. Following that, the mixture was placed within the cavity to undergo a 40-second light cure.
Group III (Composite-Ceram X): A 15-second etching procedure using 37% phosphoric acid was done then the cavity was rinsed for 15 seconds to remove any remaining acid, followed by 10 seconds of air drying. Then, a bonding agent was applied and it was light-cured for 10 seconds. The material was applied in increments up to a 2 mm depth/thickness. Depending on the light intensity, each increment underwent a 20–40 second light cure.

After restoration, the final finishing and polishing of the restorations were carried out.

Evaluation

Postoperative evaluation was done at the time interval of 1 week, 1, and 4 months, respectively. Clinical evaluation of the restored teeth was done using FDI criteria.¹⁷ This included evaluation and scoring of teeth on various parameters comprising marginal/surface staining, material fracture/retention, postoperative sensitivity, and recurrence of caries. In addition to this, internal root resorption and pulp vitality were also evaluated using intraoral periapical radiographs and electric pulp testing, respectively.

Statistical Analysis

The data was initially entered into Microsoft Excel. Statistical Package for the Social Sciences (version 25.0) and MedCalc software was used for all the statistical calculations. To determine group differences for frequency-based observations, the Chi-squared test was performed. Statistical significance was assigned to the p-value of <0.05.

Additionally, this study promoted cavity conditions with flexible base materials. Whenever there are deep and wide cavities, the clinician frequently decides to keep them as part of the restorative treatment. Higher stress levels were seen at the enamel tissue when the flowable composite was stimulated compared to GIC. When layers of the bulk-fill resin composite were added, the peaks at the dentin margin were similar, and fewer stress peaks were visible in the model after ALK was added. Clinicians are interested in bulk restorations because they require less clinical intervention and easier material placement than standard resin composites. The literature describes reduced volume shrinkage and decreased polymerization shrinkage stress.

RESULTS

Intergroup comparison between groups I, II, and III for various clinical parameters at a time interval of 1 week revealed nonsignificant differences in all the parameters, with almost all teeth showing clinically excellent to clinically good results. However, a significant difference was observed in marginal/surface staining (p = 0.004).

At the 1-month recall interval, a significant difference was observed in terms of all parameters in all three groups except the recurrence of caries which exhibited a nonsignificant difference (p = 0.407).

At a 4-month recall interval, the scores of various teeth in different groups varied from clinically excellent to clinically unsatisfactory and for all these parameters the significant, and nonsignificant changes were observed and are depicted in Figure 1. A significant difference was found in terms of marginal staining (p = 0.004), material fracture/retention (p = 0.001), marginal adaptation (p = 0.027), and postoperative sensitivity (p = 0.046). However, a nonsignificant difference was observed in the recurrence of caries (p = 0.407) may be due to following the correct oral hygiene measures now (Table 1).

**Table 1:** Intergroup comparison between groups I, II, and III for various clinical parameters at a time interval of 4 months
FDI criteria	p-value
Marginal staining	0.004
Material fracture/retention	0.001
Marginal adaptation	0.027
Postoperative sensitivity	0.046
Recurrence of caries	0.407

Fig. 1: Intergroup comparison between groups I, II, and III in terms of all the parameters of FDI

Other Parameters

Intergroup comparison between groups I, II, and III for internal root resorption and pulp vitality at a time interval of 4 months revealed a nonsignificant difference (p = 0.207) as depicted in Figure 2 and (Table 2).

**Table 2:** Intergroup comparison between groups I, II, and III for internal root resorption and pulp vitality at a time interval of 4 months
Criteria	p-value
Internal root resorption	0.207
Pulp vitality	0.207

Fig. 2: Intergroup comparison between groups I, II, and III in terms of internal root resorption and pulp vitality

In 20% of cases exhibiting the nonvital pulp/internal resorption in the composite group over a period of 4 months are due to polymerization shrinkage.

DISCUSSION

Cavitated primary teeth are generally restored with different restorative materials including amalgam, composite resin, and GICs.¹⁸ Recently launched an alkasite-based material Cention N claims to be a superior alternative to replace conventional restorative materials.

In our study, we tried to compare the success rate and clinical efficacy of Cention N, RMGIC, and composite resin in cavitated primary molars.

At the end of the 4th month, it was seen that Cention N performed better than RMGIC and composite in terms of various parameters of FDI criteria.

In terms of marginal/surface staining Cention N showed significantly better results followed by RMGIC and composite resin with 46.7 and 26.7% of samples exhibiting clinically excellent scoring in the Cention N and RMGIC groups while none of the samples exhibited clinically excellent scoring in the composite group. The results could be attributed due to the fact that with due course of time, depending on the changes in eating, drinking, and brushing behaviors, restorations absorbed the oral environment’s staining and slightly lightened the pale tint so that it blended in with other teeth.¹⁹

The result in relation to material fracture/retention showed that none of the samples of Cention N exhibited material fracture at 4 months recall. However, 6.7% of samples showed a material fracture in both RMGIC and composite groups. The result can be explained by the fact that the filler in Cention N gives the product enough strength to withstand oral cavity loads and strains and achieve suitable clinical durability.²⁰ whereas RMGIC due to degradation and wear along with its lower modulus of elasticity leads to fracture and loss of retention.⁹ In composite higher polymerization shrinkage might have resulted in microcracking of the restorative material or tooth structure.²¹ Our result was in accordance with a study conducted by Mazumdar et al. 2018²⁰ who evaluated the hardness of four restorative materials, nanohybrid composite resin, Cention N, silver amalgam, and type II GIC and concluded that Cention N showed better microhardness properties and thus was a more clinically suitable option for minimally invasive treatments.

Cention N reported maximum marginal adaptation followed by RMGIC and composite resin, with 86.7, 40.0, and 40.0% of samples reporting clinically excellent scoring, respectively. Maximum marginal adaptation of Cention N can be attributed due to low elastic modulus (10 GPA) which allows better marginal seal. The result was supported by the study conducted by Afraaz et al. 2020²² who reported better marginal adaptation with minimal gap formations for Cention N compared to composite resin restoration.

Microleakage was a major contributing factor to postoperative sensitivity. According to Sujith et al., 2020²³ Cention-N showed lesser microleakage compared with GIC and composite. In our study, Cention N displayed minimal postoperative sensitivity because it exhibits low polymerization shrinkage and low microleakage²³ followed by RMGIC and composite resin with 80.0, 46.7, and 33.3% of samples recording clinically excellent scoring in Cention N, RMGIC, and composite groups.

In terms of recurrence of caries, Cention N, and RMGIC groups reported similar results with 93.3% of samples exhibiting clinically excellent scoring but in the composite group, only 80.0% of samples exhibited clinically excellent scoring. As higher levels of fluoride ions are released by Cention N as compared to traditional glass ionomers. Additionally, it liberates hydroxide and calcium ions, which can aid in preventing demineralization of the tooth substance.²⁴ Also RMGIC significantly influences the demineralization–remineralization cycle as it has the ability to leach fluoride ions into the surrounding tooth structure, thus producing an anticaries effect.²⁵ Similar results were also obtained in a study conducted by Kevin Donly (2016 scientific documentation Cention N)²⁴ who reported that the ion-releasing materials RMGIC (Vitremer) and Cention N exhibited less demineralization at both enamel and dentin junctions.

Cention N exhibited no internal root resorption and pulpal change whereas, in RMGIC and composite groups, 13.3 and 20.0% of the samples showed internal root resorption and pulpal change. Pulpal inflammation is caused because of microleakage due to poor adaptation of the material but Cention N allows better marginal seal as also reported by Afraaz et al. 2020.²²

Therefore, based on the observations obtained in the present study. Cention N showed better clinical success when compared to RMGIC and composite resin.

This study was done under various different parameters which makes the result more accurate and convincing that Cention N can be the best restorative material that can be used in pediatric dentistry.

Limitations

Cention N is available in only one shade.
This study had only 4-month follow-up period because COVID-19 was growing tremendously at the time. Longer periods of follow-up are necessary to validate the result. Thus, long-term randomized control trials are still required to support the findings.

CONCLUSION

All the three materials used in the study that is, alkasite-based restorative material (Cention N), RMGIC (3M ESPE Vitremer), and composite resin (Ceram X) were found to be efficacious for restoring class II cavities in primary molars but Cention N proved to exhibit best performance in terms of clinical parameters followed by RMGIC and composite resin.

As a good clinical practice if the cavity is not clinically acceptable or there is sensitivity for a 1-week interval, then initially will go with desensitizing toothpaste; maintaining good oral hygiene; using a soft-bristled toothbrush.

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