Facebook users' engagement with dental caries misinformation in Brazilian Portuguese.

This study analyzed dental caries-related Facebook posts in Brazilian Portuguese to identify misinformation and predict user interaction factors. A sample of 500 posts (between August 2016 and August 2021), was obtained by CrowdTangle. Two independent and calibrated investigators (intraclass correlation coefficient varying from 0.80 to 0.98) characterized the posts based on their time of publication, author's profile, sentiment, aim of content, motivation, and facticity. Most posts (90.2%) originated from Brazil, and they were predominantly shared by business profiles (94.2%). Approximately 67.2% of these posts focused on preventive dental issues, driven by noncommercial interests in 88.8% of cases. Misinformation was present in 39.6% of the posts, particularly those with a positive sentiment and commercial motivation. Business profiles and positive sentiment were identified as predictive factors for higher post engagement. These findings highlight a significant proportion of dental caries-related posts containing misinformation, especially when associated with positive emotions and commercial motivation.