An in vitro Evaluation of Shear Bond Strength of Orthodontic Brackets after Mouth Rinse.

AIMS: The aim of the study was to evaluate the shear bond strength (SBS) of orthodontic brackets after mouth rinsing. MATERIALS AND METHODS: Sixty orthodontically extracted maxillary premolar teeth were used in the present study. Buccal surfaces of all the teeth were bonded with orthodontic bracket. Later, each tooth was embedded into acrylic resin and stored in distilled water. All the teeth were randomly divided into four groups (group I: Artificial saliva, group II: Alcohol mouth rinse- Listerine, group III: Chlorhexidine (CHX) mouth rinse-Hexidine, and group IV: Herbal mouth rinse-Befresh) and stored in each solution for 12 hours. Later, each tooth was subjected to SBS testing using universal testing machine. Brackets and enamel surfaces were examined under a stereomicroscope at 10* magnification for modified adhesive remnant index (ARI). The data were statistically evaluated using IBM Statistical Package for the Social Sciences (SPSS) Statistics for Windows, version 20.0 (IBM Corp., Armonk, New York, USA) and using one-way analysis of variance (ANOVA) and Chi-square test with significance of p < 0.05. RESULTS: Highest mean SBS was observed in artificial saliva control group (14.27 ± 0.52 MPa), followed by herbal Befresh group (11.14 ± 0.72 MPa) and CHX, and least was found in alcohol-Listerine group of 8.48 ± 0.52 MPa (p < 0.001). The ARI score showed highest bond failure for group I (ARI 14) compared to group II (ARI 11) (p < 0.001). CONCLUSION: Alcohol-containing mouth rinses should be avoided in patients during fixed orthodontic treatment because it affects the bond strength. CLINICAL SIGNIFICANCE: Shear bond strength is affected with the use of alcohol-based mouth rinse compared with herbal or CHX mouth rinses.

In vitro evaluation of shear bond strength and microleakage of different pit and fissure sealants.

AIM AND OBJECTIVES: Fissure caries is most common in children due to deep pit and fissures. Pit and fissure areas on the occlusal surface of the teeth make them susceptible to dental caries, which need to be prevented or restored. Fissures sealant reduces the risk of occlusal caries. The present study was done to evaluate microleakage and shear bond strength of various fissure sealants. MATERIALS AND METHODS: Thirty-six extracted molars were randomly allocated equally (n = 12) into three groups with three different sealants to evaluate shear bond strength and microleakage at sealant space. The shear bond strengths was evaluated with one-way analysis of variance and microleakage by Kruskal-Wallis nonparametric test using the Statistical Package for the Social Sciences version 18.0 (Chicago: SPSS Inc, 2009). RESULTS: Tetric flow (16.8 MPa) recorded the highest shear bond strength and the difference was statistically significant with enamel loc (12.8 MPa). There was no statistically significant difference in relation to microleakage (P > 0.05) in the tested groups. CONCLUSIONS: Tetric flow recorded the highest shear bond strength and the difference was statistically significant with enamel loc. However, there was no statistically significant difference among the groups regarding microleakage.