## 3 Results
### Knowledge of Oral Healthcare among Nursing Professionals  
Ten studies reported the effects of implementing oral care programs, interdisciplinary/interprofessional collaborative practice, or educational programs on the knowledge of nurses [14; 15; 16; 17; 18; 19; 20; 21; 22; 23]. In general, the implementation of such programs was found to enhance the knowledge of nurses [14; 15; 16; 17; 18; 19; 20; 21; 22; 23] (Figure 2). One non-randomized intervention trial evaluated the effect of an oral healthcare program in nursing homes on the knowledge of and attitudes towards oral health among care staff. The oral health program, which included mobile dental care, was found to significantly increase the knowledge of and attitudes towards oral health among care staff in both the intervention and control groups (both \(p<0.001\)), with the largest increase observed in the intervention group (\(p<0.001\)) [14]. In a questionnaire-based study, oral health literacy initiatives were found to increase the mean oral health literacy score from pre- to post-test (patients: 33.5%, community/parish members: 22.3%, nursing students: 20.8%, and medical students: all \(p<0.0001\)) [15]. In a Nigerian study that assessed the impact of an interdisciplinary educational intervention on nurses' knowledge of perinatal and infant oral healthcare, the mean knowledge scores of the nursing practitioners on oral hygiene, teething, trauma, caries, and oral habits were improved after the intervention and 6 months after the educational intervention compared with baseline [19]. Furthermore, interdisciplinary/interprofessional collaborative practice and educational programs were reported to improve the confidence levels and behaviors of nurses related to the promotion of oral health [17; 18; 23; 24; 25; 26; 27]. Figure 1: PRISMA flow diagram of study selection. Twenty-seven studies reported on the knowledge of oral healthcare among nursing professionals [13; 14; 15; 16; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43]. Most studies reported (n = 13) suboptimal or a lack of knowledge of oral healthcare among nurses [28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39]. Overall, 53.1% [28] to 100% [35] of nurses reported poor knowledge about oral health (Supplementary Figure S1). The mean oral health knowledge scores among nurses ranged from 3.7 (out of a maximum score of 5.0) [34] to 6.74 (out of a maximum score of 22.0) [39]. Knowledge related to oral healthcare was also reported to be linked to the educational background and experience of the nurses, with nursing practitioners and graduates having relatively better knowledge than trainee/student nurses, midwives, nurses with a diploma, and other professionals [29; 33; 36; 37; 38; 40; 41; 42]. In a cross-sectional study, nurses with a degree or above were 5 times more likely to have greater knowledge versus diploma holders (adjusted odds ratio (AOR) = 5.05; 95% confidence interval [CI]: 1.85-13.83) [33]. University hospital nurses reported greater knowledge of medication effects than nurses from regional hospitals (\(p<0.001\)). Similarly, experienced nurses were reported to have a significantly higher knowledge of medications' effects on oral health than less experienced nurses (\(\geq\)4 vs. \(<\)4 years of experience; \(p=0.048\)) [36]. In comparison to community health officers and community health extension workers, nurses were found to have better knowledge of oral health [38]. Two cross-sectional studies that surveyed the knowledge of undergraduate nursing students reported that most of them indicated a lack of knowledge on oral health topics (periodontal conditions, dental examination, oral hygiene procedure, and oral health intervention methods), as these were not taught or included in their educational curricula [29; 13]. A cross-sectional study investigated the current levels of oral-health-related content in undergraduate nursing education in New Zealand.