Comparative evaluation of shear bond strength of two adhesive systems before and after contamination with oral fluids: An In vitro study

The Effect of Salivary Contamination on the Shear Bond Strength of Seventh- and Eighth-generation Adhesive Systems

Aim

To compare the effect of salivary contamination on the shear bond strength (SBS) of seventh- and eighth-generation adhesives.

Materials and methods

Specimens were randomly divided into group I and group II, subdivided into three subgroups of 11 samples. Subgroup IA-seventh-generation uncontaminated (control); adhesive; air-dried; light cured. Subgroup IB-seventh-generation adhesive; saliva application, air-dried; light cured. Subgroup IC-seventh-generation adhesive; saliva application, air-dried, reapplication of adhesive, air-dried, light cured. Subgroup IIA- eighth-generation uncontaminated (control); adhesive, air-dried; light cured. Subgroup IIB- eighth-generation adhesive; saliva application, air-dried; light cured. Subgroup IIC-eighth-generation adhesive, saliva application, air-dried, reapplication of adhesive, air-dried; light cured. Following bonding procedure, composite resin restoration was done and subjected to SBS analysis.

Results

Mean SBS of eighth-generation adhesive was higher compared to seventh with and without saliva contamination. Reduction of SBS in seventh- and eighth-generation after saliva contamination was regained by reapplication of adhesive, which was less compared to the control [statistically significant (p < 0.05) for seventh and statistically not significant for eighth-generations].

Conclusion

The eighth-generation adhesives show better SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the SBS close to the control.

Clinical significance

Single-step self-etch adhesives are the adhesives which are currently used for bonding composite restorations to dentin. The adhesive bond strength can be adversely affected by moisture contamination, especially by saliva, which can lead to failure of restoration. So, it is imperative to study a material which gives better bond strength and is less affected by salivary contamination and effect of decontamination to regain the bond strength. The study concluded that eighth-generation adhesives showed higher mean SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the bond strength close to the control group.

How to cite this article

Mohan MC, Geetha P, Soman D, et al. The Effect of Salivary Contamination on the Shear Bond Strength of Seventh- and Eighth-generation Adhesive Systems. Int J Clin Pediatr Dent 2023;16(S-1):S63-S66.

Effect of Saliva Contamination on Shear Bond Strength of Self-etch Adhesive System to Dentin: An In Vitro Study

Aim and objective

This study aimed to evaluate the outcome of saliva contamination on shear bond strength (SBS) of a self-etch adhesive system to dentin.

Materials and methods

A total of 60 premolars were selected. Occlusal surfaces of the teeth were severed off. Three groups of 20 teeth in each were formed after the samples were randomly divided. Group I: Not subjected to any contamination (control group). Group II: Contamination with saliva occurred before coating the teeth with a self-etch adhesive system. Group III: Contamination with saliva occurred after coating the teeth with a self-etch adhesive system. After the contamination, the composite was placed with the help of a Teflon tube. Under the universal testing machine, the SBS of these samples was then tested.

Results

The data obtained after testing were analyzed using SPSS software. Statistical difference was seen between all the three groups. Group II projected the least SBS.

Conclusion

Contamination with saliva has a deleterious effect on the SBS. Contamination that occurs before the application of adhesive systems has shown considerably reduced SBS.

Clinical significance

This study successfully established that saliva contamination acts as a major factor in reducing the SBS of the bonding agent. Hence, in clinical situations, it is necessary to ensure sufficient steps are taken to eliminate or reduce the chances of contamination with saliva to aid in the success of the restoration.

How to cite this article

Chaudhari RR, Srivastava HR, Raisingani D, et al. Effect of Saliva Contamination on Shear Bond Strength of Self-etch Adhesive System to Dentin: An In Vitro Study. Int J Clin Pediatr Dent 2021;14(4):443–446.

Effect of the Time of Salivary Contamination during Light Curing on Degree of Conversion and Microhardness of a Restorative Composite Resin

Saliva contamination is a major clinical problem in restorative procedures. The purpose of this study was to evaluate the effect of the time of salivary contamination during light curing on the degree of conversion and the microhardness of a restorative composite resin. Eight groups of 10 samples for measuring the microhardness and eight groups of 5 samples for evaluating the degree of conversion were prepared. The samples of each group were contaminated with human saliva at a certain time. The first group (T0) was contaminated before light curing. The specimens in groups T2–T30 were contaminated at 2, 5, 10, 15, 20 and 30 s after the start of light curing, respectively. The samples of group T40 were contaminated after light curing. The degree of conversion and the microhardness of the specimens were measured by Fourier transform infrared (FTIR) spectroscopy and Vickers hardness testing techniques, respectively. The results of this study revealed that there were no significant differences between the groups in terms of the degree of conversion of the composite resin. Consistent with the findings for the degree of conversion, significant differences in the microhardness between the groups were not found. In conclusion, from a clinical point of view, the results of our study showed that the time of salivary contamination (before, during or after light curing of composite resin) has no significant effect on the polymerization (degree of conversion) and one of the important mechanical properties of dental composite resins (microhardness).