An In Vitro Evaluation of the Microleakage under Complete Metal Crowns Using Three Adhesive Luting Cements

Comparative Microleakage Evaluation through the Interfaces between the Tooth and Cement after Stainless Steel Crown Cementation in Primary Molars: An In Vitro Study

Introduction

The longevity of stainless steel crowns is related to perfect adaptation and long-term union between restoration and teeth. In this respect, evaluation of marginal leakage of luting cement is essential.

Aim and objective

To compare and evaluate the ability of new adhesive cement to prevent microleakage under stainless steel crowns on primary teeth.

Materials and methods

Forty-five specimens were embedded, standardized preparations were made onto selected extracted primary molars, and stainless steel crowns were adapted. Samples were assigned randomly to cement groups: Glass ionomer (GI), resin-modified glass-ionomer (RMGI), and Adhesive resin (AR) cement, followed by storage in water, artificially aging, staining, sectioning, and the linear dye penetration and proportion of microleakage evaluation.

Results

AR showed the lowest microleakage, followed in increasing order by RMGIC and GIC showed the greatest microleakage (p-value < 0.0001).

Clinical Significance

There are many kinds of luting agents that vary considerably from the viewpoint of solubility, strength, and ability to adhere to the tooth structure. Lack of adhesion of the luting cement to the tooth structure is one of the reasons for microleakage related to different types of crowns. Cement breakdown may result in the entrance of fluids and microorganisms along with the tooth restoration interface. In this study, attempts were made to simulate standard clinical procedures, although this is not a substitute for the complex oral environment, the results provide useful information to choosing the best cement materials.

Conclusion

Adhesive resin cement can be recommended for cementation of Stainless Steel Crowns because of added advantages over others.

How to cite this article

Gundewar MS, Saha S, Arora D, et al. Comparative Microleakage Evaluation through the Interfaces between the Tooth and Cement after Stainless Steel Crown Cementation in Primary Molars: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(2):159-163.

Microleakage at Implant Abutment and Prosthesis Interface in Cemented Implant-Supported Prosthesis

BACKGROUND

Dental implants have an important role in mainstream dental practice today to restore esthetics. The present study was conducted to evaluate the microleakage at implant abutment and prosthesis interface in cemented implant-supported prosthesis.

MATERIALS AND METHODS

The present study comprised sixty replicas of abutment analog with length 5 mm, width of platform 4.8 mm, and taper 6° which were milled and divided into three groups. In Group I, nickel-chromium copings were fabricated; marginal gap was evaluated with optical microscope and luted with zinc oxide noneugenol cement, Group II with zinc polycarboxylate cement, and Group III with zinc phosphate cement. Microleakage was scored by the method used by Tjan et al.

RESULTS

The mean microleakage score in Group I was 2.5, in Group II was 1.9, and in Group III was 1.05. The difference was significant (P < 0.05).

CONCLUSION

All cements showed microleakage. Minimum microleakage was seen with zinc phosphate cement than zinc oxide noneugenol cement and zinc polycarboxylate cement.

Comparative evaluation of microleakage of metallic copings luted with three different commercially available luting cements: An in vitro study

Aim

To evaluate the microleakage of metallic copings luted with three different commercially available luting cements.

Setting and Design

Comparative evaluation in vitro study.

Materials and Methods

Thirty replicas of abutment analog were milled and divided into 3 groups. Nickel chromium copings were fabricated; marginal gap was evaluated with optical microscope and luted with Zinc Oxide Non Eugenol cement, Zinc Polycarboxylate cement and Zinc Phosphate cement. After Thermocycling, cemented specimens were placed into 0.5% aqueous solution of basic fuchsin solution for 24 hours for dye penetration. Copings were longitudinally sectioned and microleakage scores were evaluated.

Statistical Analysis Used

Kruskal-Wallis analysis of variance (ANOVA) followed by Chi-Square test. Pairwise comparison of groups with Mann Whitney U test.

Result

Mean microleakage score was least for Zinc Phosphate cement (1.075 ± 0.85) followed by Zinc Polycarboxylate cement (1.80± 0.23) and most for Zinc Oxide Non Eugenol (2.1± 0.37). The results of the study were statistically significant, P < 0.05.

Conclusions

Within the limitations of the study, it was found that all cements exhibited certain amount of microleakage. Zinc Phosphate cement exhibited a mean microleakage score that was significantly lower than Zinc Oxide Non Eugenol cement and Zinc Polycarboxylate cement. When microleakage scores of Zinc Oxide Non Eugenol cement and Zinc Polycarboxylate cement were compared, the difference was found to be insignificant indicating that microleakage in these cements is similar.

Shear Bond Strength and Film Thickness of a Naturally Antimicrobial Modified Dental Luting Cement

Although several natural plants and mixtures have been known and used over the centuries for their antibacterial activity, few have been thoroughly explored in the field of dentistry. Thus, the aim of this study was to enhance the antimicrobial activity of a conventional glass ionomer cement (GIC) with natural plant extracts. The effect of this alteration on the bond strength and film thickness of glass ionomer cement was evaluated and related to an 0.5% chlorohexidine modified GIC. Olive leaves (Olea europaea), Fig tree (Ficus carica), and the leaves and roots of Miswak (Salvadora persica) were used to prepare an alcoholic extract mixture. The prepared extract mixture after the evaporation of the solvent was used to modify a freeze-dried glass ionomer cement at three different extracts: water mass ratios 1:2, 1:1, and 2:1. An 0.5% chlorhexidine diacetate powder was added to a conventional GIC for the preparation of a positive control group (CHX-GIC) for comparison. The bond strength to dentine was assessed using a material-testing machine at a cross head speed of 0.5 mm/min. Failure mode was analyzed using a stereomicroscope at 12× magnification. The cement film thickness was evaluated in accordance with ISO standard 9917-1. The minimum number of samples in each group was n = 10. Statistical analysis was performed using a Kruskal–Wallis test followed by Dunn’s post hoc test for pairwise comparison. There was a statistically insignificant difference between the median shear bond strength (p = 0.046) of the control group (M = 3.4 MPa), and each of the CHX-GIC (M = 1.7 MPa), and the three plant modified groups of 1:2, 1:1, 2:1 (M = 5.1, 3.2, and 4.3 MPa, respectively). The CHX-GIC group showed statistically significant lower median values compared to the three plant-modified groups. Mixed and cohesive failure modes were predominant among all the tested groups. All the tested groups (p < 0.001) met the ISO standard of having less than 25 µm film thickness, with the 2:1 group (M = 24 µm) being statistically the highest among all the other groups. The plant extracts did not alter either the shear bond strength or the film thickness of the GIC and thus might represent a promising additive to GICs.

The Effect of Polymerization and Preparation Techniques on the Microleakage of Composite Laminate Veneers

BACKGROUND

Marginal leakage is the important factor influencing the maintenance of dental esthetic.

AIM

The purpose of this study was to evaluate the relationship between the preparation techniques and type of polymerization techniques on microleakage of composite laminate veneers.

MATERIALS AND METHODS

Ninety-one same sized, caries-free human maxillary central incisors were randomly assigned to 13 groups (n = 7) and were designed with four different preparation techniques (window type, feather type, bevel type, and incisal overlap type). One group determined as control group and any preparation was applied. Nanohybrid resin composite was used for restoration. Composite laminate veneers polymerized with three different techniques (direct light curing, indirect polymerization with a combination of pressure, light and heat using a light cup and heat cup, direct polymerization, and additionally heat cured in an oven). The specimens were thermocycled, and then immersed in 5% basic fuchsine solution. Following 24 h, all specimens were immersed in 65% nitric acid solutions for volumetric dye extraction test. Samples diluted with distilled water and centrifuged and microleakage determined by a spectrophotometer.

STATISTICAL ANALYSIS USED

Data were analyzed with two-way ANOVA and Tukey honest significant difference post hoc multiple comparisons test (P < 0.05).

RESULTS

For comparing the microleakage value of preparation and polymerization techniques, Window type preparation showed a significant difference in direct polymerization + additional cured group (P < 0.05). Control group was statistically different from the other groups (P < 0.05).

CONCLUSIONS

Window type laminate preparation can be preferred in indirect polymerization technique because it caused less leakage in this present study.