Mechanical behavior of a bi-layer glass ionomer

Comparative Evaluation of the Survival Rates of Atraumatic Restorative Treatment Restorations Using Bilayer Technique along with Nanofilled Coating in Primary Molars: A Clinical Study

Objective

To enhance the survival rate of atraumatic restorative treatment (ART) restorations using (class I and class II) bilayer technique of placing glass ionomer cement (GIC) along with nanofilled coating (NC) over the restorations, thereby improving longevity.

Study design

A total of 178 primary molars in 67 children were selected and randomly divided into four groups. Group IA was treated with a single layer of GIC, followed by a protective layer of petroleum jelly in class I restoration. Group IB was treated with a single layer of GIC, followed by a protective layer of petroleum jelly in class II restoration. Group IIA was treated with bilayer GIC restoration followed by NC of GC-Coat Plus in class I, whereas group IIB was treated with bilayer GIC restoration followed by GC-Coat Plus in class II. Clinical analysis of all three groups was performed at 1, 3, 6, 9, and 12 months to evaluate the success of treatment procedures using predetermined criteria. Pearson's Chi-square and Kaplan-Meier estimates were utilized to evaluate the success of all four treatment procedures (p < 0.05).

Results

Out of 178 teeth, 33 teeth were in group IA, 36 teeth were in group IB, 43 teeth were in group IIA, and 40 teeth were available for evaluation at the end of the 12-month follow-up period. The overall success was determined to be 81% for group IA, 79.2% for group IB, 79.5% for group IIA, and 88.6% for IIB. At 6th-month follow-up, one clinical failure was observed in groups IA and IB. At 9 months follow-up, two clinical failures were observed in both group IA and group IB and three failures were observed in group IIB. At 12 months follow-up, four clinical failures were observed in group IA, three in group IB and one clinical failure was observed in group IIB. There was no statistically significant difference observed between the success of the four groups, suggesting that either of the techniques can be utilized for ART.

Conclusion

No statistically significant difference was observed between the survival of class I and class II restorations of both the groups, indicating that either single-layer or bilayer technique along with NC can be adopted for the management of dental caries in primary molars using the ART approach.

How to cite this article

Khan N, Garg N, Garg N, et al. Comparative Evaluation of the Survival Rates of Atraumatic Restorative Treatment Restorations Using Bilayer Technique along with Nanofilled Coating in Primary Molars: A Clinical Study. Int J Clin Pediatr Dent 2024;17(S-1):S55-S60.

In vitro wear of (resin-coated) high-viscosity glass ionomer cements and glass hybrid restorative systems

OBJECTIVES

The aim of the present study was to investigate the volumetric abrasive wear of a high-viscosity glass ionomer cement (hvGIC; Equia Fil) and a glass hybrid restorative system (ghRS; Equia Forte), each being recommended as amalgam alternatives. Both materials were applied with or without their respective resinous coating, and were compared with a conventional GIC (Ketac Fil) and a hybrid composite resin (CR; G-ænial Posterior).

METHODS

78 standardized occlusal Class I cavities were restored with the various materials (n = 13 per group). Before and after chewing simulation (30,000 cycles at 40 N), each sample underwent optical scanning procedures (Omnicam). A comparison of the total wear using a fluorescence-aided identification technique (OraCheck) followed, and differences (α = 5%) between groups were compared by means of MANOVA.

RESULTS

Regarding the wear rates of hvGIC and ghRS, no differences could be observed (p > .050), and this was not affected by the resinous coating. All hvGIC and ghRS restorations showed significantly higher abrasive wear than CR (p < .001), while the conventional GIC displayed a significant underperformance compared with any other material (p < .001).

CONCLUSIONS

Resinous coating of hvGIC or ghRS does not appear to exert an effective long-term protection against advanced abrasive wear. Compared to the conventional GIC showing a considerable substance loss, both hvGIC and ghRS materials revealed an improved abrasion resistance, but clearly failed to meet the excellent values of the CR.

CLINICAL SIGNIFICANCE

Occlusal loading should be carefully considered when using hvGIC or ghRS as amalgam (or composite resin) alternatives for the restoration of posterior teeth.

Clinical wear of approximal glass ionomer restorations protected with a nanofilled self-adhesive light-cured protective coating

High viscous glass ionomer cement (GIC) has gained popularity as a restorative material; however, high wear is pointed as one of the major drawbacks of this material. Protective surface coatings were developed to protect GIC from water contamination with the additional advantage of occluding any surface cracks or porosities commonly found in this material, possibly resulting in an increased wear resistance of the restorations.

Influence of Hand Instrumentation and Ultrasonic Scaling on the Microleakage of various Cervical Restorations: An in vitro Study

INTRODUCTION

In cervical lesions, various restorative materials can be inserted, which can be affected by the application of periodontal scalers. This study evaluated and compared the marginal seal of class V glass ionomer, composite resin, and amalgam restorations after subjecting them to hand instrumentation and ultrasonic scaling.

MATERIALS AND METHODS

In this experimental study, 30 sound human first premolars were selected. In each tooth, buccal and lingual cavities (4 mm mesiodistal width, 3 mm occlusogingival height, and 2 mm depth) were made. The teeth were randomly assigned to three groups of 10 teeth: (1) Glass ionomer group, (2) composite group, and (3) amalgam group. Teeth were subjected to thermocycling procedure for 1,000 cycles between 5 and 55°C water baths and a 1-minute dwell time. Then, each group was randomly subdivided: (1) Margins of 30 restorations were exposed to hand instrumentation procedures by applying 10 working strokes, (2) margins of 30 restorations were exposed to a periodontal tip mounted on a piezoelectric ultrasonic handpiece working at 25 kHz for 10 seconds. The specimens were serially sectioned mesiodistally. Each section was examined under a stereomicroscope. The extent of microleakage was ranked using a 0 to 4 scale at both occlusal and cervical margins of the restorations. Data were analyzed initially using the Kruskal-Wallis test, followed by multiple comparisons using the Mann-Whitney and Wilcoxon test.

RESULTS

The type of restorative material had a significant influence on dye penetration, whether in the enamel margin or in the dentinal margin (p < 0.001). The microleakage of glass ionomer group was the highest. No statistical differences were found in dye penetration between scaling groups (hand instrumentation and ultrasonic scaling) (p > 0.05).

CONCLUSION

Type of restorative material had a significant influence on microleakage. No statistical differences were found in dye penetration between scaling groups.

CLINICAL SIGNIFICANCE

The microleakage of glass ionomer restoration is greater than amalgam and composite restorations after subjecting them to hand instrumentation and ultrasonic scaling.

Bilayer technique and nano-filled coating increase success of approximal ART restorations: a randomized clinical trial

BACKGROUND

The high-viscosity consistency of glass ionomer cement (GIC) may lead to its incorrect adaptation into the cavity and therefore to restoration failure.

AIM

To compare two different insertion techniques for GIC in approximal atraumatic restorative treatment (ART) restorations and two different surface protection materials.

DESIGN

Approximal caries lesion in primary molars from 208 schoolchildren was randomly assigned into four groups: G1, conventional GIC insertion protected with petroleum jelly (PJ); G2, bilayer technique protected with PJ; G3 conventional GIC insertion protected with nano-filled particles coating for GIC (NPC); G4, bilayer technique protected with NPC. Restorations were evaluated after 1, 6, 12, 18, 24, and 36 months. Kaplan-Meier survival analysis and log-rank test were performed. Cox regression analysis (α = 5%) was used to verify the influence of clinical factors.

RESULTS

Restoration survival was 52.8%. Log-rank test indicated a better survival of the bilayer technique restorations, compared to conventional restorations (P = 0.005), whereas the coated conventional restorations presented higher survival than the uncoated ones (P = 0.035). Cox regression analysis showed no influence of any clinical tested variables.

CONCLUSION

The survival rate of the approximal ART restorations is positively influenced by the bilayer technique, and the application of nano-filled coating increases the longevity of the conventional approximal ART restorations.