## 3 Results
### Oral Care and Practices  
Six studies reported that the implementation of educational interventions and ventilator-associated pneumonia prevention programs improved oral care [46; 65; 66; 67; 68; 69]. A Japanese study showed that the percentage of undergraduate nursing students expressing a need to learn techniques for interdental cleaning significantly increased from 21.6-76.5% (at the baseline) to 65.7-95.1% (after the multi-professional education program) both in theory and in practice (\(p\) < 0.05) [46]. In a Colombian study, an educational intervention aimed at improving oral hygiene care by nursing staff was reported to reduce the incidence of ventilator-associated pneumonia in adults connected to ventilators in the ICU (from 8.9% to 2.8%). Routine oral and dental care by the nursing staff substantially increased from 29.6% to 92.8% after the intervention. In addition to the increase in the oral care among the nurses, the educational intervention also changed the oral practices of the patients (i.e., tooth brushing increased from 0.9% to 48.6%, use of chlorhexidine mouthwash increased from 2.9% to 70%, and aid participation in caring increased from 32.7% to 94.3%) [65]. Similarly, another study from the US reported that the effective implementation of oral care protocols significantly decreased the rates of ventilator-associated pneumonia by 62.5%. The frequency of oral care increased significantly to tooth brushing every 4 h and swabing every 12 h with 0.12% chlorhexidine solution (\(p\) = 0.001) [66]. In a quasi-experimental retrospective study, there was a significant increase in the adherence to preventive measures before and after continuing education/training (i.e., adherence to oral hygiene increased from 89.5% to 98.2% and tooth brushing increased from 80.8% to 96.4% (both \(p\) < 0.001)) [67]. In an Iranian study, a formal and structured education program in addition to the usual service significantly improved the performance of nurses in providing oral care for mechanically ventilated children (intervention group: 42.8 (SD: 18.5)) at baseline vs. 68.6 (SD: 31.4) at 4 weeks after the intervention (\(p\) < 0.001); control group: 48.7 (SD:15.7) at baseline vs. 48.6 (SD: 15.4)) [68]. Similarly, interpersonal education was found to improve the frequency of tooth brushing, comfort level with dental visits, oral-health-related knowledge, and overall positive responses of nursing and dental students [69].  
In addition to assessing the effect of integration of oral care practices into the training of nursing professionals, 12 studies reported on the general oral care practices of nursing professionals [4; 46; 55; 57; 61; 65; 66; 67; 68; 69; 70]. In general, there was variability observed in nursing practices related to oral healthcare. Five studies reported that nurses often used oral care solutions (saline, chlorhexidine, hydrogen peroxide solution, sodium bicarbonate solution, and distilled water/tap water) for mouthwash [4; 44; 57; 65; 70]. Various studies reported the use of foam swabs/swabbing (61-91.9%) [44; 61], moisturizers (53-98.9%) [44; 55], cotton/gauze swabs (69.9-93.5%) [55; 61], saline (20-82.7%) [61; 70], chlorhexidine (12.2-97.8%) [54; 57; 61; 70], hydrogen peroxide solution (31.8%) [61], sodium bicarbonate solution (20.8-75.6%) [61; 70], distilled water/tap water (4.3-17.9%) [55; 61; 70], mouthwash (57.8-88.2%) [55; 70], toothbrushes (17.8-70%) [44; 70], suction toothbrushes (93.5%) [55], and manual toothbrushes (49.5%) [55] for oral care.