ABSTRACT
PURPOSE: Denture Stomatitis, a chronic mucosal inflammation associated with Candida albicans, is common among denture wearers. Several health conditions have been linked to chronic Candida infections. The complex, multifactorial nature of denture stomatitis requires the continuous pursuit of effective long-term solutions. The present in vitro study investigated the effect of incorporating organoselenium into 3D-printed denture base resin on C. albicans adhesion and biofilm formation. MATERIALS AND METHODS: Thirty disks were fabricated using 3D-printed denture base resin and assigned to three experimental groups (10/group): disks without organoselenium (control), disks with 0.5% organoselenium (0.5%SE), and disks with 1% organoselenium (1%SE). Each disk was incubated with approximately 1 × 106 cells/mL of C. albicans for 48 h. Microbial viability (CFU/mL) was quantified by the spread plate method, while Confocal laser scanning microscopy and scanning electron microscope were performed for quantifying the biofilm thickness and examining biofilm morphology, respectively. Data were analyzed using One-way ANOVA with Tukey's multiple comparisons test. RESULTS: CFU/mL was significantly (p < 0.05) higher in Control when compared with 0.5%SE and 1%SE, but no significant difference between 0.5%SE and 1%SE. A similar trend was observed with biofilm thickness except that there was no significant difference between the Control and 0.5%SE. There was C. albicans biofilm adhesion on the Control disks, with yeast cells and hyphae formation, whereas on 0.5%SE and 1%SE, there was inhibition of yeast cells transition to hyphae formation. CONCLUSIONS: Incorporation of organoselenium into 3D-printed denture base resin was effective in reducing C. albicans biofilm formation and growth on denture base material.
ABSTRACT
To date, there has been a lack of published studies examining the validity of the Health Sciences Reasoning Test (HSRT) to assess critical thinking among dental students. The aim of this study was to examine the construct validity of the HSRT using a novice-expert model consisting of first-year dental students as novices and experienced general dentists as experts. Novice cohort subjects were recruited from all 105 students in the first-year dental school class at the University of Texas Health Science Center at San Antonio during a regularly scheduled course in August 2015. A total of 83 students participated, for a 79% response rate. Thirty individuals personally recruited from the same school's faculty and from private practitioners made up the expert cohort. The results showed that the adjusted mean overall score for the expert cohort (25.31) was significantly higher than that of the novice cohort (22.64) (p=0.04). The expert cohort achieved higher adjusted mean scores in all scales (Induction, Deduction, Analysis, Inference, and Evaluation), with the difference in the Analysis scale being significant (p=0.02). In this study, experienced general dentists achieved significantly better overall scores on the HSRT as compared to first-year dental students, suggesting the instrument was able to measure differences between novice and expert. Further efforts to validate the instrument in a dental education setting and to understand its correlation with strategies and practices aimed at developing critical thinking in dental students are warranted.
