The 4th Chinese National Oral Health Survey showed that people's oral health knowledge and attitudes had been greatly improved, but caries and periodontal diseases remain serious problems, and people's oral health behaviour is far from standard. Oral health behaviour education for adults might be an efficient way of addressing this issue. For some reasons, we focused on undergraduates with the aim of improving themselves and indirectly helping children and elderly people.
Previous study showed that oral health care knowledge and behaviour of dental students were better than non-dental students . For dental students at Sichuan University, education for oral health started in their first year. Some clinical research or practice was open to them, such as the university students' innovation and entrepreneurship training programme. Additionally, some of them had opportunities to get in touch with seniors and obtain information. The third year is the first year of professional dental education. Preclinical education and practice can enhance dental students’ knowledge and behaviour of oral health. For non-dental students who had similar general education backgrounds as dental students, the difference might come from preclinical oral health education. Therefore, we used the dental group as a reference to identify the differences or gaps in oral health knowledge and behaviour between the two groups. Additionally, we explored the role of OHE focused on oral health behaviour in both dental and non-dental students by comparing their oral health knowledge and attitudes before and after the course.
The toothbrushing frequency was well known among all the students. However, half of non-dental students did not meet the recommended brushing time of two minutes. Additionally, non-dental students had difficulty selecting a tooth brushing method. The (modified) Bass method, the Roll method, the Fones method and the horizontal method are the most widely used brushing methods . Study has shown that the (modified) Bass technique is effective in controlling dental plaque and alleviating gingival inflammation . The horizontal method, which could result in wedge-shaped defects, is not recommended. However, it is a common method in China. In this survey, less than one-fifth of the non-dental students used the Bass method, but more than two-fifth of them used incorrect methods. From these results, we concluded that although non-dental students had good brushing frequency, their brushing time and actual brushing methods may not be appropriate.
Interproximal cleaning was extremely overlooked by both dental and non-dental students. It was surprising that few dental students floss for daily cleaning. The findings revealed signs of ignorance about interproximal cleaning in China. Floss is so efficient that it can remove up to 80% of plaque . However, floss is comparably difficult to use, which may limit its application . Moreover, toothpicks have a history of more than a thousand years in China and are deeply rooted in Chinese people’s minds . Toothpicks are quite popular in China and can easily be found in restaurants and take-away-cutlery. Interestingly, the tendency to use toothpicks increased among non-dental students after the course. OHE on avoiding the use of toothpicks should be strengthened to minimize periodontal damage caused by improper use.
Function and price were the most important considerations when students chose toothbrushes. A study confirmed that electric toothbrushes were more effective than manual toothbrushes . Before the course, more than half of the students in both groups thought electric toothbrushes were better than manual toothbrushes. However, the actual use rate was much lower, especially in the non-dental group. Furthermore, nation-wide usage is much lower. A report showed that the penetration rate of electric toothbrushes in China was only 5%, while in some developed countries, it was more than 15% and even up to 40% . Price might be a possible reason. After the introduction of electric toothbrushes during the course, more students realized their advantages and intended to use them, even at a higher price. If electric toothbrushes are not popular because of their high price, we should strengthen OHE on the use of manual toothbrushes instead of emphasizing the use of electric toothbrushes.
When choosing toothpaste, function and price were also the first two considerations. Interestingly, more non-dental students than dental students were willing to use Chinese herbal toothpaste before and after the course. As a part of traditional Chinese medicine, Chinese herbal toothpaste may have some effects in alleviating gingival inflammation  and preventing caries . Chinese have partiality for Chinese herbal toothpaste. Its correct usage should be addressed in future courses on OHE; for example, when facing gingival bleeding caused by periodontitis, relying on herbal toothpaste instead of scaling may worsen the disease.
One issue that cannot be ignored is that some students cared about popularity when choosing toothpaste and toothbrush. This suggests us a new method of OHE: new media. Recently, a large number of popular media platforms have emerged. WeChat, an interactive social media platform in China, has a wide range of young users and is used frequently every day . A study showed that passive acquisition (moments, public accounts, group chat) of health information through WeChat was an important medium for college students . Taobao, a large online shopping platform, is preferred by young people and carries many traditional and emerging oral care products endorsed by celebrities, which is very attractive to young people who are starstruck and pursuing popularity. At the same time, it contains a wealth of pictures, videos and instructions for the products. In addition to traditional classes, WeChat groups, WeChat public accounts and Moments can be used for regular OHE, to be a reminder of flossing and to update new knowledge that is not included in textbook. Taobao links can provide vivid information about oral hygiene products, making OHE much more convenient and cost-effective.
Overall, the majority of students realized their shortcomings in oral health behaviour and had a strong willingness to improve. Our OHE course focused on behaviour played a positive role for university students. Dental students had much better performance than non-dental students in terms of toothbrushing frequency, method, and time and floss use. This suggests that dental students know more details about oral health care. Future OHE should pay more attention to flossing, toothbrushing methods, toothpicks, Chinese herb toothpaste and modifications to adopt new media.
As a quasi-experimental study, the grades and sample numbers of dental and non-dental students were different. The post-course survey was conducted within a short period of time. The long-term change in students' knowledge, attitudes and behaviours is unknown. Furthermore, our survey did not include clinical examinations.