RESUMO
Purpose: To evaluate and compare the tooth-whitening potential of five over-the-counter (OTC), peroxide-free dental bleaching methods as well as an experimental tooth-whitening solution containing 0.1% hydrogen peroxide complexed with doping agents with a gold standard (positive control) containing 16% carbamide peroxide. Material and Methods: Eighty permanent bovine incisor teeth were randomly allocated to eight different groups. Two teeth from each group were immerged into five staining solutions represented by coffee, tea, red wine, and curry mixed in warm oil or distilled water (control group) and stored at 37 °C for 28 days in an incubator. The teeth were then reallocated to the eight groups, resulting in ten samples per group, and each group was matched with a bleaching product. The bleaching procedures were executed following the manufacturer's recommendations. The color of each sample was assessed over a white and black background using a quantitative numerical measurement approach with a calibrated spectrophotometer. Spectrophotometric measurements were performed after exposing the teeth to the bleaching agent for 60 min (T2), 100 min (T3), and 200 min (T4), and ΔE00 was calculated. Results: When analyzed over a white background, the mean ΔE00 values ranged from 2.14 (placebo) to 6.32 (Opalescence PF). When analyzed over a black background, the mean ΔE00 values ranged from 2.31 (placebo) to 5.78 (Opalescence PF). Statistically significant ΔE00 color changes over time for the eight groups and five staining solutions at T1 and T4 were assessed for both backgrounds using repeated ANOVA followed by Fisher's LSD post hoc test (p-value < 0.01). Conclusions: All tested over-the-counter whitening kits except one exhibited positive color variation. However, the individual performance differed vastly from one brand to the other, and the overall performance was less effective compared to the conventional carbamide-peroxide-based positive control.
RESUMO
In this digital era, dental students often search for online resources for self-directed learning. YouTube is one of the most commonly sought online platforms for educational or instructional videos. No prior study has examined the validity of panoramic radiography videos available on YouTube. This study provides a content analysis of these YouTube videos. A search for relevant YouTube videos was conducted in April 2022. The search string was: (panoramic OR pan OR OPG) AND (dental OR dentistry OR X-ray). The first 100 videos that resulted from the search and their related videos were screened. Exclusion criteria included irrelevance (e.g., no demonstration of panoramic radiography procedures) and non-English videos. For each included video, the following parameters were recorded: image receptor type, patient age, patient type (real patient, animation, or phantom head), patient preparation procedures, machine preparation, patient positioning, and operator safety. The number of views, comments, likes, and channel subscribers were recorded, as well as the video duration and the age of the video. Forty videos were included and analyzed. Most of the videos demonstrated digital panoramic radiography with an adult patient. Procedures on the patient and machine preparations as well as patient positioning were generally explained well. However, most videos did not well-demonstrate operator safety details concerning the use of adequate personal protective equipment. View count, comment count, and channel subscriber count positively correlated with the like count. Clinicians and students should carefully critique the content of such instructional videos and refer to the contents from other sources such as user manuals and latest recommendations from local authorities.
