Clinical performance of a resin-modified glass-ionomer and two polyacid-modified resin composites in cervical lesions restorations: 1-year follow-up

Do bioactive materials show greater retention rates in restoring permanent teeth than non-bioactive materials? A systematic review and network meta-analysis of randomized controlled trials

OBJECTIVES

To answer the following research question: does the clinical evaluation of restorations on permanent teeth with bioactive materials show greater retention rates than those with non-bioactive materials?

MATERIALS AND METHODS

A search strategy was used in the following databases: MEDLINE via PubMed, Scopus, Web of Science, LILACS, BBO, Embase, The Cochrane Library, and OpenGrey. Randomized controlled trials (RCTs), with a minimum of 2-year follow-up and evaluating at least one bioactive material in permanent teeth were included. Risk of bias was detected according to the Cochrane Collaboration tool for assessing the risk of bias (RoB 2.0), and network meta-analysis was performed using a random-effects Bayesian-mixed treatment comparison model.

RESULTS

Twenty-seven studies were included. The success of the restorations was assessed using modified USPHS system in 24 studies and the FDI criteria in 3 studies. Network meta-analysis revealed three networks based on restoration preparations. Resin composites were ranked with higher SUCRA values, indicating a greater likelihood of being the preferred treatment for class I, II, and III restorations. In class V, resin-modified glass ionomer cement was ranked with the highest value.

CONCLUSION

Bioactive restorative materials showed similar good clinical performance in terms of retention similarly to conventional resin composites.

CLINICAL SIGNIFICANCE

The findings must be interpreted with caution because many RCT on restorative materials aim to verify the equivalence of new materials over the gold standard material rather than their superiority. The present systematic review also suggests that new RCT with longer follow-up periods are necessary.

The preventive effect of glass ionomer cement restorations on secondary caries formation: A systematic review and meta-analysis

OBJECTIVE

The objective is to compare the preventive effect on secondary caries of glass ionomer cement (GIC) restorations with amalgam or resin-composite restorations.

METHODS

Two independent researchers conducted a systematic search of English publications in PubMed, Web of Science, Cochrane and Scopus. They selected randomized clinical trials comparing secondary caries incidences around GIC restorations (conventional GIC or resin-modified GIC) with amalgam or resin-composite restorations. Meta-analysis of the secondary-caries incidences with risk ratio (RR) and 95% confidence interval (95% CI) as the effect measure was performed.

RESULTS

This review included 64 studies. These studies included 8310 GIC restorations and 5857 amalgam or resin-composite restorations with a follow-up period from 1 to 10 years. Twenty-one studies with 4807 restorations on primary teeth and thirty-eight studies with 4885 restorations on permanent teeth were eligible for meta-analysis. The GIC restorations had a lower secondary caries incidence compared with amalgam restorations in both primary dentition [RR= 0.55, 95% CI:0.41-0.72] and permanent dentition [RR= 0.20, 95% CI:0.11-0.38]. GIC restorations showed similar secondary caries incidence compared with resin-composite restorations in primary dentition [RR= 0.92, 95% CI:0.77-1.10] and permanent dentition [RR= 0.77, 95% CI:0.39-1.51]. Conventional GIC restorations showed similar secondary caries incidence compared with resin-modified GIC-restored teeth in both primary dentition [RR= 1.12, 95% CI:0.67-1.87] and permanent dentition [RR= 1.63, 95% CI:0.34-7.84].

CONCLUSIONS

GIC restorations showed a superior preventive effect against secondary caries compared to amalgam restorations, and a similar preventive effect against secondary caries compared to resin-composite restorations in both primary and permanent teeth. [PROSPERO Registration ID: CRD42022380959].

Clinical Effectiveness of a Resin-modified Glass Ionomer Cement and a Mild One-step Self-etch Adhesive Applied Actively and Passively in Noncarious Cervical Lesions: An 18-Month Clinical Trial

OBJECTIVES:

To evaluate the clinical effectiveness of two methods of application of a mild one-step self-etch adhesive and composite resin as compared with a resin-modified glass ionomer cement (RMGIC) control restoration in noncarious cervical lesions (NCCLs).

METHODS:

A total of 294 restorations were placed in 56 patients, 98 in each one of the following groups: 1) G-Bond active application combined with Solare-X composite resin (A-1SEA), 2) G-Bond passive application combined with Solare-X composite resin (P-1SEA), and 3) GC II LC RMGIC. The restorations were evaluated at baseline and after six, 12, and 18 months according to the FDI criteria for fractures/retention, marginal adaptation, marginal staining, postoperative sensitivity, and secondary caries. Cumulative failure rates were calculated for each criterion at each recall period. The effect of adhesive, method of application, and recall period were assessed. The Kruskal-Wallis test for intergroup comparison and Friedman and Wilcoxon signed ranks tests for intragroup comparison were used for each criterion ( α=0.05).

RESULTS:

The retention rates at 18 months were 93.26% for the A-1SEA group, 86.21% for the P-1SEA group, and 90.91% for the RMGIC group. The active application improved the retention rates compared with the passive application of mild one-step self-etch adhesive; however, no statistically significant difference was observed between the groups. Marginal staining was observed in 13 restorations (1 in A-1SEA, 4 in P-1SEA, and 8 in RMGIC) with no significant difference between the groups. The RMGIC group showed a significant increase in marginal staining at 12 and 18 months from the baseline. There was no significant difference between the groups for marginal adaptation, secondary caries, or postoperative sensitivity.

CONCLUSION:

Within the limitations of the study, we can conclude that mild one-step self-etch adhesive followed by a resin composite restoration can be an alternative to RMGIC with similar retention and improved esthetics in restoration of NCCLs. Agitation could possibly benefit the clinical performance of mild one-step self-etch adhesives, but this study did not confirm that the observed benefit was statistically significant.

Characterization of fluoride releasing restorative dental materials

This study aimed to evaluate and compare certain mechanical properties, Vickers-hardness, water sorption, fluoride-release, shrinkage-stress and wear of five commercial fluoride-releasing restorative materials (Dyract, CompGlass, BEAUTIFIL II, ACTIVA-Restorative, and GC Fuji II LC), in relation to their microstructural characteristics. Mechanical properties were determined for each material following ISO standards. A wear test was conducted with 15,000 chewing cycles using a dual-axis chewing simulator. Daily fluoride-release was measured during the first 10 days by using a fluoride ion selective electrode. Scanning electron microscopy (SEM) was used to evaluate the microstructure of each material. Results were statistically analysed using ANOVA followed by post hoc Tukey's test. ACTIVA-Restorative exhibited the highest fracture toughness (1.1 MPa m^1/2) among the materials tested. BEAUTIFIL II presented the highest flexural strength (145 MPa) which was not significantly different (p>0.05) from CompGlass and Dyract. Highest fluoride-release measurement was located for GC Fuji II LC among other tested materials.

Antimicrobial Capacity of Casein Phosphopeptide/Amorphous Calcium Phosphate and Enzymes in Glass Ionomer Cement in Dentin Carious Lesions

OBJECTIVE

To evaluate the ability of casein phosphopeptide/amorphous calcium phosphate (CPP/ACP) and lysozyme, lactoferrin, and lactoperoxidase (LLL) added to glass ionomer cement (GIC) to inhibit the growth of S. mutans in a caries model.

MATERIAL AND METHODS

Eighty permanent third molars were selected. The dentin of these teeth was exposed and flattened. Except for the coronal dentin, the specimens were waterproofed, autoclaved, and submitted to cariogenic challenge with standard strain of S. mutans. The carious lesions were sealed as follows: group 1 (n=20): GIC without additives; group 2 (n=20): GIC + CPP/ACP; group 3 (n=20): GIC + LLL; group 4 (n=20): GIC + CPP/ACP + LLL. S. mutans counts were performed before the caries were sealed (n=5), after 24 hours (n=5), at 1 month (n=5), and at 6 months (n=5). The results were analyzed using descriptive statistical analysis and the Kruskal-Wallis test (Student-Newman-Keuls test).

RESULTS

GIC + LLL caused a significant reduction of S. mutans 1 month after sealing (p<0.01); however, there was a significant growth of S. mutans 6 months after sealing. GIC, GIC + CPP/ACP, and GIC + CPP/ACP + LLL showed similar behavior with significant reduction of S. mutans after 24 hours (p<0.05) and increase after 1 and 6 months.

CONCLUSION

The addition of LLL to GIC increases the antimicrobial action of GIC on S. mutans. This leads to control of bacterial biofilm for 1 month, thus stopping the progression of carious lesions.

A Retrospective Clinical Study of Cervical Restorations: Longevity and Failure-Prognostic Variables

The aim of this retrospective clinical study was to compare the longevity of cervical restorations between resin composite (RC) and glass ionomer (GI) and to investigate variables predictive of their outcome. The clinical performance of the two restorative materials in function was compared using the ratings of the modified United States Public Health Service (USPHS) criteria. A total of 479 cervical restorations were included in the study. Ninety-one already-replaced restorations were reviewed from dental records. The other 388 restorations still in function were evaluated according to the modified USPHS criteria by two investigators. Longevity and prognostic variables were analyzed with the Kaplan-Meier survival analysis and multivariate Cox proportional hazard model. The clinical performances of the two materials were evaluated according to the ratings of the USPHS criteria and compared using the Pearson chi-square test and Fisher exact test. The longevity was not significantly different between RC and GI (median survival time, 10.4 ± 0.7 and 11.5 ± 1.1 years, respectively). The main reasons for failure were loss of retention (82.2%) and secondary caries (17.8%). The longevity of cervical restoration was significantly influenced by tooth group and operator group (Wald test, p&lt;0.05), while material, gender, presence or absence of systemic diseases, arch, and reason for treatment did not affect the longevity. Contrary to the longevity, the clinical performance of RC was superior to GI in the criteria of retention, marginal discoloration, and marginal adaptation, but similar in secondary caries, wear, and postoperative sensitivity.

Two-year clinical evaluation of resinous restorative systems in non-carious cervical lesions

This controlled clinical trial evaluated the 2-year clinical performance of a one-bottle etch-and-rinse adhesive and resin composite system (Excite/Tetric Ceram) compared to a resin-modified glass ionomer cement (RMGIC) (Vitremer/3M) in non-carious cervical lesions. Seventy cervical restorations (35 resin composite - RC- restorations and 35 RMGIC restorations) were placed by a single operator in 30 patients under rubber dam isolation without mechanical preparation. All restorations were evaluated blindly by 2 independent examiners using the modified USPHS criteria at baseline, and after 6, 12 and 24 months. Data were analyzed statistically by Fisher's exact and McNemar tests. After 2 years, 59 out of 70 restorations were evaluated. As much as 78.8% retention rate was recorded for RC restorations, while 100% retention was obtained for RMGIC restorations. Fisher's exact test showed significant differences (p=0.011) for retention. However, there were no significant differences for marginal integrity, marginal discoloration, anatomic form and secondary caries between the RC and RMGIC restorations. The McNemar test detected significant differences for Excite/TC between baseline and the 2-year recall for retention (p=0.02), marginal integrity (p=0.002) and anatomic form (p=0.04). Therefore, the one-bottle etch-and-rinse bonding system/resin composite showed an inferior clinical performance compared to the RMGIC.

Long-term dentin retention of etch-and-rinse and self-etch adhesives and a resin-modified glass ionomer cement in non-carious cervical lesions

OBJECTIVES

The aim of this study was to evaluate the clinical long-term retention to dentin of seven adhesive systems.

METHODS

A total of 270 Class V restorations of four etch-and-rinse, one self-etch adhesive system and a resin-modified glass ionomer cement were placed in non-carious cervical lesions without intentional enamel involvement. The restorations were evaluated at baseline, 6, 12, 18, and 24 months and then every year during a 13-year follow-up. Dentin bonding efficiency was determined by the percentage of lost restorations.

RESULTS

During the 13 years, 215 restorations could be evaluated. The cumulative loss rate at 13 years was 53.0%, with significant different failures rates for the different systems varying between 35.6 and 86.8%. Four systems fulfilled the ADA 18-month full acceptance retention criteria. Two systems showed at 18 months and earlier high debonding rates. The annual failure rates for the etch-and-rinse systems were Optibond 3.1%, Permagen 13.0%, Scotchbond MP 4.8%, Syntac classic 2.8%; for the self-etch system P&S 4.4%; and the resin-modified glass ionomer cement Vitremer 2.7%.

CONCLUSION

It can be concluded that all systems showed a continuous degradation of the bond with a wide variation, which was independent of the adhesion strategy. Three bonding systems showed a cumulative failure rate after 13 years between 36 and 41% with the best retention for the resin-modified glass ionomer cement and a four-step etch-and-rinse system.

Effect of adhesive systems associated with resin-modified glass ionomer cements

The bonding of resin-modified glass ionomer cements to dentin remains a challenge in clinical routine. In an attempt to improve this property, different materials and techniques have been proposed. This study investigated the shear bond strength of resin-modified glass ionomer cements (Vitremer, 3M/ESPE and Fuji II LC Improved, GC) to human dentin using two one-bottle adhesive systems (Prime & Bond 2.1, Dentsply and Single Bond, 3M/ESPE). The restored specimens were stored in deionized water for 24 h at 37 +/- 1 degrees C, and then the bonded surfaces were tested in shear strength using a Universal testing machine at a crosshead speed of 0.5 mm min(-1). Bond strength means were recorded and failure modes were assessed with a stereomicroscope at 40x magnification. Data were submitted to two-way anova and multiple comparisons were performed using a Tukey statistical test (P < 0.05). Fuji II LC Improved yielded higher bond strength (P < 0.05) than Vitremer in all experimental conditions. No statistically significant differences (P > 0.05) were observed among the proposed dentin surface treatments, although a slight decrease in bond strength was observed when phosphoric acid was used alone. Bond strengths of the resin-modified glass ionomer cements to dentin seemed to be more material-dependent than surface treatment-dependent. It may be concluded that the one-bottle adhesive systems tested in this study did not improve the bond strength of the resin-modified glass ionomer cements to dentin.

Ion release by resin-modified glass-ionomer cements into water and lactic acid solutions

OBJECTIVES

This study was undertaken to gain a fuller picture of the interaction of resin-modified glass-ionomers with aqueous solutions in terms of water sorption, solution buffering and ion-release.

METHODS

Two commercial materials were employed (Fuji II LC, GC; Photac Fil Quick, 3M ESPE). Light-cured cylindrical specimens (6mm highx4mm diameter) were prepared and stored for up to 6 weeks in either water (pH 5.3) or aqueous lactic acid (2.7), six specimens of each materials per storage medium. Solutions were changed at weekly intervals. Specimens were weighed at weeks 1, 2, 4 and 6; solution pH values measured, and Na, Ca, Sr, Al, P and Si ion release determined using ICP-OES. Results were analysed by ANOVA.

RESULTS

Materials altered solution pH, and gained mass under all conditions. However, the net mass gain in lactic acid declined with time, suggesting that water sorption was partly offset by erosion under acid conditions. Na, Ca, Sr, Al, P and Si were detected in all solutions, with greater amounts in lactic acid than in water. Phosphorus release was much lower than found previously for conventional glass-ionomers.

SIGNIFICANCE

Like their conventional counterparts, resin-modified glass-ionomers have been found to buffer their storage media and release ions. Hence the resin phase does not significantly alter these aspects of the interaction with aqueous solutions.

The Clinical Repair of Teeth Using Direct Filling Materials: Engineering Considerations

This paper reviews the way in which teeth damaged by caries may be repaired clinically. The mechanical effects of caries are described, as are the materials available to repair the damage caused by this disease. Studies are reported which have shown that caries reduces the compressive strength of the tooth to less than 50 per cent of its original value and that, by use of appropriate materials and placement techniques, this can be restored to some 80 per cent of this value. However, very few studies have been carried out which view tooth repair from an engineering perspective. Instead, emphasis is placed on determining clinical durability of repairs. This is related to repair strength but brings in other factors, such as the oral hygiene of the patient. Despite this complication, durability studies show that modern restorative materials perform well under clinical conditions, from which it may be concluded that the repair process allows a structure to be fabricated that is essentially sound from an engineering view-point, even if inferior to the original tooth structure provided by nature.

Polyacid-modified composite resins ("compomers") and their use in clinical dentistry

OBJECTIVES

This paper describes the chemistry and properties of polyacid-modified composite resins ("compomers") designed for use in clinical dentistry, and reviews the literature in this area.

METHODS

Information has been obtained from over 50 published articles appearing in the dental and biomaterials literature, with studies being principally identified through MedLine.

RESULTS

Published work shows that polyacid-modified composite resins constitute a discrete class of polymeric repair material for use in dentistry. Their distinction is that they contain hydrophilic components, and these cause water to be drawn into the material following cure. This triggers an acid-base reaction, and gives the materials certain clinically-desirable properties (fluoride release, buffering capability) that are also associated with glass-ionomer cements. The water uptake leads to a decline in certain, though not all, physical properties. However, clinical studies have shown these materials to perform acceptably in a variety of applications (Class I, Class II and Class V cavities, as fissure sealants and as orthodontic band cements), especially in children's teeth.

CONCLUSIONS/SIGNIFICANCE

Polyacid-modified composite resins constitute a versatile class of dental repair material, whose bioactivity confers clinical advantages, and which are particularly useful in children's dentistry.

Changes in scattering and absorption properties of esthetic filling materials after aging

OBJECTIVES

Assuming that color changes after aging are related to changes in translucency of materials, the purpose of the present study was to determine the correlation between the changes in color and the changes in scattering and absorption properties after accelerated aging with representative dental esthetic restorative materials: glass ionomer, resin-modified glass ionomer, compomer, and resin composite.

METHODS

Color was measured according to the CIELAB color scale in the transmittance and reflectance modes and used to calculate changes in color (deltaE*(ab)), color coordinates (deltaL*, delta a*, and delta b*), translucency parameter (deltaTP), scattering coefficient (deltaS), absorption coefficient (deltaK), and light reflectivity (deltaRI) after accelerated aging. Simple correlations between each pair of the changes in optical values were calculated, and multiple regression analysis was used to determine the parameters influencing the changes in color and color coordinates (p = 0.05).

RESULTS

In the resin composite and compomer, deltaS, deltaK, and deltaRI values were approximately zero, whereas deltaS was as high as 8.9 in the glass ionomer. For most comparisons, correlation coefficient (r) was between 0.700 and 0.997. DeltaL* was found to have a major influence on color changes, and deltaS, deltaTP, and deltaRI influenced deltaL*. Therefore, changes in scattering and absorption properties, after aging, were closely correlated with changes in color and color coordinates, especially in glass ionomer-based filling materials.