This review aims to identify and describe oral health education programmes provided to patients living with CVD within hospital wards and outpatient clinics; as well as discuss any effect they had on health outcomes.

The initial search commenced 21st December 2022 and was repeated on 14th August 2023. The final search occurring 7th May 2024. Electronic databases used include Cochrane, Medline (via Ovid), and Scopus. No limitations were placed on language or publication period, and no human filter was applied. Grey literature included phrase searching via Google Scholar, as well as reviewing citation lists of relevant studies. The search strategy included a combination of the following terms “cardiovascular disease, heart disease, education relating to dental health, oral health, health promotion, digital education, video education, patient education, health knowledge, oral hygiene instruction, hospital, oral health, oral care, dental care, preventative dentistry, video recording, video-audio media.” Boolean operators (AND/OR), medical subject headings (MeSH), and truncations were also utilised. For the full search see Supplementary material 2. Every attempt was made to retrieve studies that were inaccessible including web searches, using The University of Sydney library resources, and lastly, attempting to contact corresponding authors.

The population comprised of adults ≥18 years who had been or were recently hospitalised as a result of cardiovascular disease. The intervention included digital and/or traditional oral health education being delivered to these patients within hospital wards or out-patient clinics. Any studies where oral hygiene education took place outside of the hospital environment, or within a dental setting were excluded. Only peer-reviewed publications of randomised controlled trials, quasi-randomised controlled trials, observational studies, including cohort, case–control and cross-sectional studies were eligible for inclusion. Conference abstracts, case-studies/series, letters to the editors, and editorials were excluded. Any non-English or animal studies were manually excluded.

Using Covidence, a systematic review software (35), 7,133 identified citations were imported into the programme where 1,695 duplicates were automatically removed. A further 12 duplicates were manually removed leaving a total of 5,426 for screening. Titles and abstracts were screened independently by LC and one of four alternate reviewers (LR, AT, LQ, FX). Most results did not relate to oral health education, CVD, adults, and/or were not based within a hospital setting. As such they were deemed irrelevant. Twenty-three articles were identified for further assessment, however after full text screening, a total of 3 studies [1 quasi-randomised (36) and 2 randomised controlled trials (37, 38)] met the inclusion criteria (see Figure 1). Any conflicts arising during the screening process were resolved via group discussion. A data extraction tool developed within Covidence was completed independently first by LC, followed by either LR, FX, AT, or LQ. Key characteristics extracted were author(s), publication year, country, study design, aim(s), setting, mean age, sex, outcomes measures, a comparison of oral hygiene intervention, intervention duration, and outcomes. Due to the heterogeneity of the studies, data synthesis has been presented narratively with reference to supporting material.

Three studies were identified (36–38), and included a total of 245 participants. See Table 1. The studies took place in either Hong Kong or Japan and spanned between 2013 and 2019. Participants recruited into the studies were patients who were within either a cardiac surgical or stroke rehabilitation hospital ward or were attending a hospital out-patient rehabilitation clinic. Across all studies, the lowest mean age of participants was 66.6 ± 10.8, the highest 70.9 ± 11.1; 60.6–68% were male. Whilst Omori et al. (36) did not discuss employment status, two thirds of Dai et al.’s (37) (housewife: 12.8%, retired: 51.1%, and unemployed: 2.1%), and close to three quarters of Lam et al.’s (38) subjects were not working (53.1% retired, 19.8% homemaker). All studies reported a lack of regular oral hygiene practices at baseline (36–38), and reported no significant difference in oral hygiene status between intervention groups at baseline.

The primary outcome measures for two studies (37, 38) included measures of oral hygiene status using the Silness and Löe plaque index (39, 40) and the gingival bleeding index (41). See Tables 2, 3 for indices criteria. Secondary outcomes included gingival bleeding at 6 months (37) or oral functional status, assessed by patients’ ability to perform toothbrushing and insert/remove their dentures (38). The outcome measures for one study (36) was the number of oral bacteria on the tongue, followed by oral hygiene status, periodontal parameters, tongue coating scores, self-efficacy scale for self-care (SESS) scores, and the incidence of postoperative atrial fibrillation (AF). This study also assessed plaque score by using O’Leary’s plaque control record method (43).

The education provided in each trial focused on oral hygiene instruction and was delivered by oral health practitioners or dental assistants. Each intervention differed in its methods and materials, with follow ups of 3-weeks (38), 3- and 6-months (37), and discharge (approximately 1 month) (36). See Table 4 for intervention details. In the first study, stroke patients attending their outpatient rehabilitation were placed into one of two arms control: conventional oral hygiene care programme (COHCP) or intervention advanced oral hygiene care programme (AOHCP). The control arm receiving an oral hygiene care programme, manual toothbrush, regular toothpaste (Colgate), and one on one oral hygiene instruction with a dental assistant. Whilst the intervention arm received the care programme, toothpaste, and one on one instruction however, also received an electric toothbrush with manufacturer’s instructions and a 3-month supply of chlorhexidine (CHX) mouth rinse (37).

Similarly, investigators from another study involving CVD patients within a surgical ward (36), placed them into one of two arms. Both arms received similar interventions including oral hygiene instruction, using disclosing solution, interdental brush use delivered by certified dental hygienists. The hygienists also provided post-operative oral care to a small number of participants in each group. However, the teaching method differed between the groups. The control group received skills-based teaching, the intervention arm received oral hygiene instruction via a modified behavioural six-step method (44). See Table 5 for this method.

The final study (38) included three arms: one control and two interventions. Each arm received oral hygiene instruction, whilst the intervention arms also received chlorhexidine (CHX) mouth rinse alone or in combination with 2 x weekly assisted brushing. The hygiene instruction was performed by a registered dentist and CHX was administered by ward nurses. The intervention arm receiving assisted brushing, had this performed by trained ward nurses. Training involved a 30-min education session run by dental hygienists. The authors deemed it unethical to include a negative control group due to their high risk of developing aspirational pneumonia (45).

All 3 studies reported a lack of regular oral hygiene practices at baseline (36–38). At their conclusion, all found an improvement in toothbrushing habits, whilst one (36) reported a significant increase of interdental brush use. All study arms had significant reductions in oral hygiene measures including plaque scores (p = <0.001) (36–38), improved periodontal parameters, and tongue coating scores (36). Gingival bleeding was also reduced in all arms of two studies (p 0.004) (36), (p < 0.001) (37), however, one (38) reported significance in the intervention groups only (p = 0.032). One study assessed tongue bacterial numbers (36), and reported significantly less bacteria (x10⁷cfu/mL) on participant tongues (p < 0.02), as well as fewer days with post-operative AF in the intervention group (1.5 ± 2.8 vs. 4.8 ± 7.6 p = 0.019). It also reported that 5 patients (4 control and 1 intervention) developed pneumonia (36), whereas no patients developed pneumonia in the other studies (37, 38). A 6-month follow-up was conducted in one study and they reported the continuation of plaque reduction (p = 0.05) and a further reduction in bleeding on probing (p < 0.01) in their intervention arm (37). SESS was measured in one study, showing worsened scores in the control arm (36).

The education strategies employed in all included studies involved traditional face-to-face education (36–38) and many of the excluded studies provided this education to nursing staff only (59–63). Nurses can face many challenges when providing oral care. From a personal level, barriers can include staffing issues, lack of time or training, or aversion to this care (25). This is reflected by a study where nurses admitted to ceasing toothbrushing altogether after the study period, even after oral hygiene was proven to eliminate ventilator assisted pneumonia due to the lack of time and because oral care was of low priority (61). However, challenges can also arise at the organisational level where training, resources and/or appropriate staff numbers are not provided (25).

Furthermore, patients themselves can prevent nurses from providing oral care with aggressive behaviour, care refusal, communication issues, or where oral health is not prioritised (25). As such OHPs including dentists, dental hygienists, and oral health therapists, could be an appropriate alternative to help ease this burden on nursing staff (26). The FDI World Dental Federation also recognises the benefit OHPs would have within primary healthcare settings, calling for them to be integrated into these settings globally by 2030 (64). Currently however, resulting from a lack of political leadership, low oral health prioritisation on political agendas, as well as staffing, infrastructure, and funding obstacles (65), few countries are taking steps to utilise them in this way (66).

One cost-effective way to bring oral health education to patients in these settings is through the use of digital technology. Digital CVD education programmes have been used to improve heart health outcomes (30, 33), including text-message health tips post cardiac event (67). Whilst currently oral health messages are not included, they could easily be incorporated into these existing education packages. Another solution could be providing oral health training to non-dental clinicians such as pharmacists, general practitioners, and other allied health professionals, as many individuals visit these clinicians when they have a dental issue (68).

A long-term solution at the organisational level could be a collaboration between universities and hospitals forming placements for student OHPs. Placements such as this have shown to benefit both students, hospital staff, and patients alike (69). Students placed in hospital settings would provide oral health education, assist with oral care, and with mobile dental units becoming more readily available, urgent treatment could be completed bedside (70). Additionally, referral pathways within the hospital system could also be created, utilising hospital dental clinics where applicable.

The number of eligible studies that involved the direct provision of oral health education to patients with CVD within hospital settings were limited and predominately located in Hong Kong (37, 38) or Japan (36) between 2013 and 2019. These findings highlight the need to conduct more studies in different global communities. All included studies reported generalised poor oral health in their participants at baseline, similar to recent research within a Romanian emergency hospital (71) and an Australian cardiac rehabilitation clinic (72). Both concluding further oral health education in these spaces are needed (71, 72).

A lack of resources and funding means OHPs are absent from hospital multidisciplinary teams (57, 58). Poor oral health is a modifiable risk factor for CVD however, Appropriately, priority is given to patients’ heart health in cardiology wards however, current literature acknowledges poor awareness of the links between oral and heart health in patients within cardiology wards and outpatient clinics (58, 59). This could be related to the absence of an OHP within these settings and compounded by the limited oral health messages in CVD education (25, 60–62).

This review has discussed oral health education programmes provided to patients with CVD in hospital settings. It has highlighted gaps where an OHP and/or digital technologies would be ideally placed to bridge them. As such, there are opportunities for future research and implementation of oral health education programmes for patients with CVD within hospital settings. Preferably oral health education should form part of primary prevention strategies for good general health, however incorporating it as part of secondary prevention strategies should also be a priority.

This review has highlighted the significant role oral health education plays in improving the long-term oral health in patients within hospital settings, as well as lowering the risk of common post-operative and post-stroke complications. Despite the important role oral health can play in cardiovascular health, this review has highlighted a lack of oral health education available to patients with CVD and proposed simple strategies to deliver these messages. The implementation and standardisation of programmes such as these may help to empower at-risk patients at their most vulnerable to improve their oral health for better general health.

The small number of eligible studies was a major limitation for this review. The three included studies took place in Hong Kong or Japan and thus may not be generalisable to CVD patients globally. However, a strength of this study is it is the first known review to analyse oral health education programmes provided to patients with CVD in hospital settings, highlighting a lack of oral health education in these spaces.