Objective: To evaluate the content and quality of videos created by artificial intelligence (AI) video generator platforms, specifically focused on oral hygiene maintenance and dietary advice for orthodontic patients. Methods: This mixed-method study evaluated five AI video generation platforms: InVideo, VEED.IO, VideoGen, Lumen5 and Steve.AI. A standardised base prompt was used across all platforms, with minor modifications to accommodate each tool’s limitations and functionality. Two orthodontists assessed the content of the voice-overs and captions using a checklist for oral hygiene (OHC) and dietary advice (DAC), as well as the Global Quality Scale (GQS) for overall quality. Descriptive analysis evaluated the consistency between voice-over, captions and visuals. A thematic qualitative analysis was conducted, and quantitative comparisons of checklist scores across platforms were made using non-parametric tests. Results: All videos were rated poorly, each receiving a GQS score of 2, indicating limited usefulness for patient education. VideoGen recorded the highest OHC score, while Steve.AI (Live) recorded the lowest. For the DAC, Lumen5 achieved the highest score, whereas InVideo and VEED.IO obtained the lowest. However, the score between all the platforms for DAC and OHC were not statistically different ( P > 0.05). Although flossing advice and fluoride toothpaste recommendations were generally included, key details, such as brushing duration and specific dietary instructions, were often missing. Many videos also contained irrelevant or inaccurate visuals. Thematic analysis identified three main themes: oral hygiene maintenance, dietary advice and orthodontic appointments. Conclusion: This study found that AI video generation platforms produce content of poor quality and relevance for oral hygiene maintenance and dietary advice for orthodontic patients.