Resin-based pit-and-fissure sealants: microleakage reduction and infiltration enhancement using a bonding agent

Comparison of a resin-based sealant with a nano-filled flowable resin composite on sealing performance of marginal defects in resin composites restorations: a 36-months clinical evaluation

OBJECTIVES

Our goal was to evaluate the clinical behavior of resin-based composite (RBC) restorations with sealed marginal defects using nano-filled flowable RBCs (FRS) compared with resin-based sealant (RBS); this work used marginal adaptation, marginal staining, and secondary caries according to the World Dental Federation (FDI) criteria.

MATERIALS AND METHODS

This was a prospective, randomized, double-blind, controlled trial. Fifty-four patients who met the inclusion criteria (older than 18 years old; with high cariogenic risk determined by Cariogram software; and restorations with marginal defects, 3 and 4 according to FDI criteria) were randomly divided into three groups. There were three defective RBC restorations per patient and were repaired (n = 162). The groups were RBS-marginal sealing using a resin-based sealant (Clinpro Sealant, 3 M ESPE, MN, USA) plus adhesive (Single Bond Universal, 3 M ESPE, MN, USA); FRS-sealing using flowable resin (Filtek Flow Z350XT, 3 M ESPE, MN, USA) plus adhesive (Single Bond Universal, 3 M ESPE, MN, USA); and control-no repair treatment. All procedures were performed under complete isolation. Evaluations were evaluated at 1-week post treatment (baseline) as well as at 18 and 36 months after treatment regarding marginal adaptation, marginal staining, and secondary caries according to FDI criteria. The data were analyzed using the Wilcoxon test (α = 0.05) to compare the differences in each treatment group at different evaluation times.

RESULTS

Marginal adaptation of micro-repaired RBC restorations were seen in patients with a high risk of caries using flowable resin composite or resin-based sealants. There were differences (P < 0.001) when baseline was compared at 18 and 36 months. Marginal staining showed differences when baseline was compared to 18 months (P < 0.001) and 36 months (P = 0.001) for both treatments. Secondary caries parameters for RBS treatment showed differences when baseline was compared to 36 months (P = 0.025) and when 18 months was compared to 36 months (P = 0.046).

CONCLUSIONS

Micro-repair of RBC restorations resulted in clinical deterioration of marginal adaptation and marginal staining. Nano-filled flowable resin composites were sealed on defective restorations; 3 and 4 FDI marginal defects have better clinical performance to prevent secondary caries than resin-based sealants after 36 months.

CLINICAL RELEVANCE

Micro-repair with RBS does not seem to be an effective treatment to prevent secondary caries.

Effect of Precuring and Postcuring of Total-Etch and Self-Etch Bonding Agents on the Microleakage of Fissure Sealants

Objectives:

Considering the importance of timesaving in pediatric dentistry, if the efficacy is achieved along with shorter working time and less technical sensitivity, the behavior management of young patients can be anticipated. This study aimed to compare the effect of precuring and postcuring of total-etch and self-etch bonding agents on the microleakage of sealants.

Materials and Methods:

This study was conducted on forty impacted third molars, which were surgically extracted. The samples were divided into five groups: 1. Control (etching and sealant), 2. Precured fifth-generation bonding agent (Adper Single Bond 2) and fissure sealant, 3. Postcured fifth-generation bonding agent (Adper Single Bond 2) and fissure sealant, 4. Precured seventh-generation bonding agent (Single Bond Universal) and fissure sealant, and 5. Postcured seventh-generation bonding agent (Single Bond Universal) and fissure sealant. All specimens were thermocycled (×1000), immersed in 0.5% basic fuchsine solution for 24 hours, sectioned, digitally photographed, and measured using the LAS EZ program. The data were analyzed using Kruskal-Wallis and Dunn’s tests.

Results:

Leakage in the control group and the third group was significantly lower than that in other groups. In pairwise comparisons, a significant difference was found between the control group and the fifth group and between the third group and the fifth group.

Conclusion:

The conventional method of sealant placement showed superior results in comparison with the use of an intermediate layer of the bonding agent.

Integrity testing of a smooth surface resin sealant around orthodontic brackets using a new Fluorescence-aided Identification Technique (FIT)

OBJECTIVE:

To investigate the integrity of a fluorescing resin-based sealant placed around orthodontic brackets using the Fluorescence-aided Identification Technique (FIT).

MATERIALS AND METHODS:

Standard brackets were bonded to the buccal surfaces of 17 extracted sound permanent premolar crowns sealed with ProSeal^®. Specimens were thermocycled (20,000 cycles, 5-55°C), and toothbrushing was simulated using an electric toothbrush and artificial aqueous toothpaste slurry. Changes in the sealed area were measured after one, two, three, and four alternating thermocycling-brushing cycles simulating 2 years of wear. Digital images were captured applying FIT (405 nm) using a digital camera-equipped stereomicroscope. ImageJ was used to measure sealant integrity and loss.

RESULTS:

There was a time-dependent decrease in sealed areas by between 21% and 100% (mean 54%). The sealant lost its integrity immediately after the first cycle, and unfilled areas were observed in all samples.

CONCLUSIONS:

The analyzed sealant lost its integrity over time. Using the proposed FIT, sealed surfaces were easily verified and quantified.

Sealing effectiveness of fissure sealant bonded with universal adhesive systems on saliva-contaminated and noncontaminated enamel

Background

The effectiveness of sealants is dependent upon their adhesion to enamel surface. The aim of the study was to evaluate the sealing ability of a pit and fissure sealant used with a universal adhesive (etch-and-rinse vs. self-etch modes) when the site is contaminated with saliva. Adhesive properties were evaluated as microleakage and scanning electron microscopic (SEM) characteristics.

Material and Methods

A total of 72 mandibular third molars were randomly divided into 6 groups (n=12). Occlusal pits and fissures were sealed with an unfilled resin fissure sealant (FS) material with or without saliva contamination. The groups included: 1) phosphoric acid etching + FS (control), 2) phosphoric acid etching + Scotchbond Universal (etch-and-rinse) + FS, 3) phosphoric acid etching + saliva + Scotchbond Universal (etch-and-rinse) + FS, 4) Scotchbond Universal (self-etching) + FS,5) Scotchbond Universal (self-etching) + saliva + FS, and 6) Scotchbond Universal (self-etching) + saliva + Scotchbond Universal + FS. After thermocycling, the teeth were placed in 0.5% fuchsin, sectioned, and evaluated by digital microscopy. Two samples from each group were also observed by SEM. The data were analyzed with Kruskal-Wallis and Mann-Whitney tests for a significance of p<0.05.

Results

There were significant differences among groups. Groups 1,2 and 4 showed the least microleakage, with no significant differences among groups. Saliva contamination led to increased microleakage and gap formation in SEM images in groups 3, 5 and 6.

Conclusions

The fissure sealing ability of the universal adhesive in etch-and-rinse or self-etch modes was similar to that of conventional acid etching. Saliva contamination had a negative effect on sealant adhesion to pretreated enamel. Key words:Pit and fissure sealant, Universal adhesive, Saliva.