IADR Abstract Archives
EFFECT OF DIFFERENT MOUTH WASHES ON SURFACE MICROHARDNESS OF MICROHYBRID AND NANOCOMPOSITE. AN-IN VITRO STUDY
Objectives: To evaluate and compare the surface microhardness of microhybrid (P60) and nanocomposite (Z350XT) with Listerine CoolMint (Containing alcohol/ethanol), Colgate Plax (alcohol/ethanol free), Clinica (Chlorhexidine) mouthwashes and distilled water with different immersion times.
Methods: 128 circular disc shape specimens (diameter: 6mm and thickness: 2mm) were prepared with microhybrid and nanocomposite and divided into 2 groups. Group A contains 64 specimens of microhybrid and Group B contains 64 specimens of nanocomposite. All the specimens were stored in distilled water for 24 hours at 37°C. The initial microhardness test was carried out for baseline measurement (To) by Vickers microhardness tester. According to the treatment solution 64 samples in each group divided into 4 subgroups (A1, A2, A3, A4) (B1, B2, B3, B4). Half of the specimens from each subgroup were immersed in 20ml of treatment solution and stored for 12 hours at 37°C and half were stored for 24 hours. Specimens were re-subjected to microhardness testing device for measuring microhardness (T1) after 12 hours and (T2) after 24 hours immersion. The values obtained as base line and final Vickers hardness number for each specimen was subjected to statistical analysis by using one - way ANOVA and post-hoc tukey’s t-test.
Results: Statistical analysis revealed that nanocomposite showed highly significant reduction in surface microhardness as compared to microhybrid composite (p<0.001). Listerine (alcohol / ethanol containing) mouthwash produced the greatest degradation effect (p<0.001).
Conclusions: Mouthwashes in all groups reduced the microhardness of both composite resins irrespective of presence of alcohol. Microhybrid composite exhibited significantly higher VHN compared to nanocomposite with all the mouthwashes and distilled water . Among all mouthwashes listerine presents a higher potential in reducing the microhardness of both composite resins whereas distilled water has a little effect on it . The effect of mouthwashes on microhardness of a composite material depended on the type of mouthwashes, exposure time and the composition of composite resin.
Methods: 128 circular disc shape specimens (diameter: 6mm and thickness: 2mm) were prepared with microhybrid and nanocomposite and divided into 2 groups. Group A contains 64 specimens of microhybrid and Group B contains 64 specimens of nanocomposite. All the specimens were stored in distilled water for 24 hours at 37°C. The initial microhardness test was carried out for baseline measurement (To) by Vickers microhardness tester. According to the treatment solution 64 samples in each group divided into 4 subgroups (A1, A2, A3, A4) (B1, B2, B3, B4). Half of the specimens from each subgroup were immersed in 20ml of treatment solution and stored for 12 hours at 37°C and half were stored for 24 hours. Specimens were re-subjected to microhardness testing device for measuring microhardness (T1) after 12 hours and (T2) after 24 hours immersion. The values obtained as base line and final Vickers hardness number for each specimen was subjected to statistical analysis by using one - way ANOVA and post-hoc tukey’s t-test.
Results: Statistical analysis revealed that nanocomposite showed highly significant reduction in surface microhardness as compared to microhybrid composite (p<0.001). Listerine (alcohol / ethanol containing) mouthwash produced the greatest degradation effect (p<0.001).
Conclusions: Mouthwashes in all groups reduced the microhardness of both composite resins irrespective of presence of alcohol. Microhybrid composite exhibited significantly higher VHN compared to nanocomposite with all the mouthwashes and distilled water . Among all mouthwashes listerine presents a higher potential in reducing the microhardness of both composite resins whereas distilled water has a little effect on it . The effect of mouthwashes on microhardness of a composite material depended on the type of mouthwashes, exposure time and the composition of composite resin.