Self-etch bonding agent beneath sealant: Bond strength for laser-irradiated enamel

An In vitro Assessment of the Shear Bond Strength of Two Different Pit and Fissure Sealants in Primary Teeth

Aim

The current research had an aim to evaluate the shear bond strength of two different pit and fissure sealants in deciduous teeth.

Materials and Methods

Forty deciduous teeth were part of this research. Inclusion criteria were teeth having an unbroken occlusal surface, whereas samples having developmental defects/afflicted with caries were subjected to exclusion from this research. Each specimen tooth was assigned at random to one of the two groups constituting 20 specimens each by means of a computer-generated randomization with two alphabets (A, B). Group 1: Conventional sealant, Group 2: Self-adhering flowable sealant. Following sealant coating, a shear load was placed via a universal testing apparatus in a manner parallel to the bonded edge at a speed of 0.5 millimeter/minute till the occurrence of a breakdown. Bond strength was subsequently measured in Mega Pascals (MPa).

Results

13.86 ± 0.23 was the mean shear bond strength of self-adhering flowable sealant versus 11.48 ± 0.52 Mpa of conventional sealants. Statistically significant differences amid both groups were noted.

Conclusion

The current research arrived at a conclusion that self-adhering flowable sealants exhibited superior shear bond strength in comparison to conventional sealants.

Microleakage Assessment of Two Different Pit and Fissure Sealants: A Comparative Confocal Laser Scanning Microscopy Study

Introduction

Pit and fissures of permanent dentition are considered to be highly vulnerable to the adhesion of cariogenic microorganisms and consequently result in caries formation. The main problem associated with sealant failure will be microleakage. Therefore, sealants can be considered to be an effective preventive procedure for dental caries, only if it strongly bonds to the tooth, and protect the pit and fissures from the oral bacterial environment.

Aim and objective

To compare and assess the microleakage of two different pit and fissure sealants on permanent molars.

Materials and methods

A total of 20 extracted third molars were randomly divided into two groups where group I is conventional sealant and group II is hydrophilic sealant. Occlusal surfaces of permanent molars were treated with 37% orthophosphoric acid before sealant placement. Tooth samples were subjected to 0.1% rhodamine dye immersion, thermocycling, and tooth samples were sectioned and evaluated under a confocal laser microscope for dye penetration. A non-parametric test (Mann–Whitney U) was performed to compare the mean microleakage score difference between the groups.

Results

Group II (hydrophilic sealant) showed a minimum level of the microleakage score when compared to group I (conventional sealant) and was found to be statistically significant using the Mann-Whitney U test with a p value <0.05.

Conclusion

The less the microleakage, the better will be the retention of the sealant for a longer duration and cariostatic action.

How to cite this article

Prabakar J, Indiran MA, Kumar P, et al. Microleakage Assessment of Two Different Pit and Fissure Sealants: A Comparative Confocal Laser Scanning Microscopy Study. Int J Clin Pediatr Dent 2020;13(S-1):S29–S33.

Assessment of microleakage of class V restored by resin composite and resin-modified glass ionomer and pit and fissure resin-based sealants following Er:YAG laser conditioning and acid etching: in vitro study

Aim

The aim of this study was to make a comparison between microleakage of conventionally restored class V cavities using acid etchant and the ones conditioned by erbium-doped yttrium aluminum garnet (Er:YAG) laser, and also to assess and compare the effectiveness of enamel surface treatments of occlusal pits and fissures by acid etching and conditioned by Er:YAG laser-etch.

Materials and methods

Seventy-two extracted third molars were used in this study. The samples were divided into two major groups: class V cavities and pit and fissure sealants. Each subgroup was divided into conventional acid etching, Er:YAG laser conditioning and conventional acid etching, and combination with Er:YAG laser conditioning (n=12). The teeth were placed in 2% methylene blue dye solution, were sectioned, and were evaluated according to the dye penetration criteria. Two samples per subgroup were chosen for scanning electron microscopic (SEM) analysis.

Results

There was a significant difference between occlusal and cervical margin groups. Laser conventional composite cementum group showed more microleakage values compared to other groups. There was no significant difference between occlusal margin groups. However, there was a significant difference between cervical margin groups in terms of microleakage. In sealant groups, there was a significant difference between laser and conventional with/without laser treatment groups in terms of microleakage.

Conclusion

Based on the results reported in this study, it can be concluded that the application of the Er:YAG laser beneath the resin composite, the resin-modified glass ionomers (GIs), and the fissure sealant placement may be an alternative enamel and dentin etching method to acid etching.

In vitro Comparative Evaluation of Tensile Bond Strength of 6(th), 7(th) and 8(th) Generation Dentin Bonding Agents

BACKGROUND

Newer dentin bonding agents were developed to improve the quality of composite restoration and to reduce time consumption in its application. The aim of the present study was to evaluate tensile bond strength of 6(th), 7(th) and 8(th) generation bonding agents by in vitro method.

MATERIALS AND METHODS

Selected 60 permanent teeth were assigned into 20 in each group (Group I: 6(th) generation bonding agent-Adper SE plus 3M ESPE, Group II: 7(th) generation bonding agent-G-Bond GC Corp Japan and Group III: 8(th) generation dentin adhesives-FuturaBond, DC, Voco, Germany). With high-speed diamond disc, coronal dentin was exposed, and selected dentin bonding agents were applied, followed by composite restoration. All samples were saved in saline for 24 h and tensile bond strength testing was done using a universal testing machine. The obtained data were tabulated and statistically analyzed using ANOVA test.

RESULTS

The tensile bond strength readings for 6(th) generation bonding agent was 32.2465, for 7(th) generation was 31.6734, and for 8(th)-generation dentine bonding agent was 34.74431. The highest tensile bond strength was seen in 8(th) generation bonding agent compared to 6(th) and 7(th) generation bonding agents.

CONCLUSION

From the present study it can be conclude that 8(th) generation dentine adhesive (Futura DC, Voco, Germany) resulted in highest tensile bond strength compared to 6(th) (Adper SE plus, 3M ESPE) and 7(th) generation (G-Bond) dentin bonding agents.