Atherosclerotic disease

Atherosclerosis, the pathologic narrowing of arteries due to the deposition of cholesterol and cholesterol products in vessel walls, is the primary cause of most cases of coronary heart disease and cerebrovascular disease.^[17] Patients with a history of myocardial infarction or cerebrovascular strokes had poorer dental health than healthy people, according to studies conducted many years ago.^[17], ^[18] The most common risk factors for cardiovascular disease include high blood cholesterol, hypertension, diabetes, and smoking. Chronic inflammation, metastatic infection, and endotoxin-induced vascular injury are all possible etiologies of cardiovascular disease based on the oral cavity, according to literature.^[19]

Gingival inflammation and bacteremia are common and severe in patients with periodontal disease and poor dental hygiene, both of which trigger the host inflammatory response.^[20] Multiple proinflammatory cytokines, such as C-reactive protein, tumour necrosis factor, interleukin 1 and interleukin 6, can be triggered by this chronic inflammatory state, which, when combined with bacteremia, appear to stimulate atherogenesis and increase the susceptibility of the vascular endothelium to injury. Streptococci of the viridans group can also cause platelet aggregation and thrombus formation during bouts of oral bacteremia.^[20], ^[21] Although it has been established that periodontal disease and poor dental hygiene are strongly linked to the risk of coronary heart disease and acute myocardial infarction, other studies have not found this link; as a result, there is insufficient evidence to establish a causative relationship.^[15], ^[21] Improving oral health would lower the risk of serious illnesses with high morbidity and death.^[21]

Pulmonary disease

The aspiration of microorganisms from the oropharynx to the lower respiratory tract is involved in pulmonary disorders such as chronic obstructive pulmonary disease (including emphysema), pneumonia, and exacerbations of chronic bronchitis.^[22] Patients with endotracheal and orogastric tubes, swallowing problems, and diminished consciousness were thought to be the only ones at risk of aspiration at first. According to research, up to 50% of healthy people aspirate their oropharyngeal secretions while sleeping.^[15]

Ventilator-associated pneumonia (VAP), for example, is a life-threatening nosocomial infection and is associated with aspiration of bacteria from the oropharynx and leakage of contaminated secretions around the endotracheal tube.^[23] The bacteria responsible for VAP colonize the oral mucosa and the dental plaques of intubated patients.^[24]

The oral apparatus, which includes teeth, periodontium, and biofilm, can house and serve as reservoirs for pathologic bacteria, and the presence of periodontal disease alters the environment, making attachment and proliferation easier for pathogens.^[21] The body has numerous layers of protection to prevent microorganisms from entering the lower respiratory system, so the progression of an infection is complicated and depends on more than just the presence of bacteria. These defenses are impaired in critically ill and intubated patients, and several intervention trials have demonstrated that improved oral hygiene reduces the risk of ventilator-associated pneumonia in ventilated critical care patients.^[15], ^[17] The evidence on the causality and relationship between lung infections and oral health is equivocal, however it appears to be heading in the direction of a positive unidirectional link. Boosting the oral hygiene of institutionalized and ventilated patients has been shown in high-quality research to have a positive impact on their systemic health.^[20]

Diabetes mellitus

Diabetes is a disease of disrupted glycemic control resulting from a lack of insulin production (type 1) or systemic insulin resistance (type 2). Diabetes affects 34.2 million individuals, according to the National Diabetes Statistics Report 2020.^[25] Diabetes presents a number of obstacles to the patient, with chronic hyperglycemia being the primary cause of the diabetes's long list of complications. Continuous hyperglycemia has negative consequences for the heart, eyes, kidneys, and peripheral nerves, and periodontal disease is regarded as a primary diabetic complication.^[12], ^[26]

The link between diabetes and periodontitis is clearly bidirectional, as hyperglycemia has been shown to have a poor impact on dental health, and severe periodontitis can have a deleterious impact on glycemic control.^[21] Diabetics are at least three times more likely than non-diabetics to develop periodontitis. According to research, Patients with well-controlled diabetes, on the other hand, have no higher risk of periodontitis than those who do not have diabetes.^[13], ^[20]

Diabetes has a lot of consequences, including increased alveolar bone loss, abscess formation, and poor healing.^[17] Diabetics suffer from all of these oral issues as a result of long-term hyperglycemia, which causes the formation of advanced glycation end products.^[21] Their end products have a variety of systemic effects, including increased cytokine excretion, which causes local inflammation and connective tissue loss. Local inflammation in the oral cavity causes systemic repercussions such as glycemic control difficulties and an increased risk of infection, explaining the condition's bidirectional relationship.^[22] Although it is evident that periodontal disease has a deleterious impact on diabetes, its effects are adjustable, and therapies can significantly improve patient health.^[21]

Other conditions

In osteoporosis, there is an imbalance between bone loss and creation, resulting in lower bone mineral density. Reduced bone density in the jawbone causes more alveolar bone resorption, which increases the depth and number of periodontal pockets, allowing bacteria to invade.^[21] This persistent infection can cause an increase in interleukin 6, which is a known predictor of bone loss both locally and systemically. Although there is insufficient evidence to conclude that periodontal disease causes osteoporosis, certain research have found a link between the two illnesses.^[21], ^[22]

Periodontal disease and other oral problems are common in persons with chronic renal disease. These oral disorders can cause infection, protein depletion, systemic inflammation, and the formation of atherosclerotic plaques, all of which can increase mortality and morbidity in people with chronic kidney disease. Although treating periodontal disease is unlikely to have a significant favorable influence on patients with chronic renal disease, enhancing the patient's overall health cannot be detrimental.^[27]

Mechanically ventilated patients

Ventilation-associated pneumonia is the most common nosocomial infection in intensive care units (ICUs), with the risk of developing pneumonia increasing at a rate of 1-3 percent per day of intubation, indicating a 6-20-fold increased risk of developing pneumonia compared to non ventilated ICU patients 2. These patients spend more time in the ICU and spend an average of an extra 7-9 days in the hospital.^[28], ^[29] Transfer of oral infection due to poor oral hygiene is the most common cause of ventilation-associated pneumonia in the ICU.33 When an endotracheal tube(ET) is inserted, the majority of the body's defenses against pneumonia are weakened . Because there is no humidification or nasal warming, this ET tube avoids the regular filtration and physical trapping functions. The ET tube inhibits mucociliary defense mechanisms and disrupts normal mucosa clearance, resulting in secretions being collected above the cuff and contaminating the subglottic pool.

Contaminated secretions leak into the trachea, where they might be inhaled. This ET tube can also stop coughing. Normal healthy adults' oral flora differs from critically ill adult patient’s oral flora. Within 48 hours of intubation, fibronectin levels drop, causing Gram-negative bacteria to outnumber Gram-positive bacteria.^[2] Dental plaque can form on the teeth within 72 hours if good oral hygiene is not practised, acting as reservoirs for possible respiratory diseases. Alongside mastication and swallowing, saliva also plays an important part in oral clearance. Bacterial growth is inhibited by lysozyme, a key enzyme found in saliva. External factors in the ICU might contribute to increased mucosa dryness, increasing the likelihood of cavities, periodontal disease, and other issues. The amount of biofilm adhered to the patient's teeth increases as the number of oral bacteria rises.^[30]

Published recommendations

Oral Care for Intubated Patients

Oral assessment can be done casing Modified Beck Oral Assessment Scale^[38] and Mucosal Plaque Score.^[39]

A dentist performs a comprehensive oral examination to check the state of the lips and intraoral soft tissues, as well as look for any hard or soft tissue pathology. Nurses are the best people to do the general assessment. Every health-care facility must have a defined oral care protocol and training plan in place to ensure that patients receive consistent, complete oral care.^[40]

There is no clear agreement on how often oral hygiene should be performed.^[32] The recommended frequency for oral cleansing was 2-hourly in a research by Cutler and Davis, where a structured protocol was created to manage oral hygiene care practice, although they noticed that in practice it fluctuated between 2- and 4-hour intervals and suggested more investigation.^[33] Other authors agree, recommending that critical care nurses work together to produce evidence-based recommendations to guide best practices in the critical care unit.^[32] The usage of toothbrushes instead of foam swabs for removing dental plaque was found to have a significant benefit.^[32]

Since a adult toothbrush is too large to reach the intubated patient's mouth, a soft-bristled 'baby' toothbrush is recommended.^[33] It allows for easier access to all areas of the mouth and can be used to clean the tongue and gums in edentulous patient.^[2], ^[32]

Brushing teeth using a child-size brush removes more dental plaque and bacteria than foam swabs([Figure 1]). Despite this information, nearly 80% of respondents reported using toothbrushes and toothpaste only occasionally.^[31] Non-intubated patients used toothpaste and toothbrushes more frequently, but intubated patients used a sponge toothette more frequently.^[34]

In surveys, critical care nurses described using a toothbrush just 38.9% of the time to offer dental care to intubated patients.2 Cotton and foam swabs are another frequently applied form of mouth care, despite evidence that using a toothbrush is superior to foam swabbing. Studies show that swabbing is still the favored method of dental care in critical care units confirming this experience.^[35], ^[31] Swabbing procedures are said to be ineffective at removing plaque.^[35], ^[32] The foam stick can be used to keep the mouth wet between brushings.^[35] Although toothpaste isn't necessary for plaque removal, topical fluoride treatments have long been thought to be significant in the prevention of decay. Non-foaming toothpaste is preferable because it can be washed out of the mouth more easily, as toothpaste buildup might dry out the mucosa.^[32] Intubated (sodium chloride, peroxide mixture, chlorhexidine) and non-intubated (mouthwash, toothbrush, toothpaste) patients used different oral care items, according to Hanneman and Gusick.^[42]

The literature discusses a range of mouth rinses, and the following is a summary:

Chlorhexidine([Figure 2]), at concentrations of 0.1 to 0.2 percent, inhibits Gram-positive and Gram-negative bacteria as well as yeast. Chlorhexidine is a slow-release agent with antibacterial activity lasting up to 12 hours.^[32], ^[44]

Sodium bicarbonate mouthwash 1 percent - is a cleansing agent that has been shown to lower the viscosity of oral mucus, allowing for better oral debris removal. Because it can induce mucosal irritation, it's critical to use it at the prescribed concentration. However, there have been no documented randomized controlled studies in the critical care population to support its use above any other mouth rinse.^[32]

Although hydrogen peroxide is an acidic solution, it must be diluted properly before use to avoid mucosal irritation. Subjective complaints of soreness and mucosal injury have been reported in groups of healthy people who used hydrogen peroxide mouthwashes. With the benefits of toothbrushes established, the use of hydrogen peroxide-impregnated foam sticks in critically ill patients is not recommended.^[32]

Sodium chloride can promote healing of oral mucosal lesions because of its tendency to cause drying, but routine use as a mouth rinse is limited in the critical care setting.^[32]

Water can be used to clean teeth and gums in combination with a small, soft-bristled toothbrush or as a solo agent to rinse and remoisten the oral cavity. Tap water in hospitals has been identified as a major source of waterborne nosocomial infections, particularly those caused by Pseudomonas. ^[4] The use of tiny bottles of sterile water as a mouth rinse in intensive care patients could be cost-effective. ^[32] Ice chips can be used to relieve oral dryness, make patients more comfortable, and control bacterial overgrowth. ^[45]

Povidone-iodine-Although povidone-iodine may be effective in the treatment of mucosal ulcers following surgery, it is of uncertain benefit as a daily mouth rinse for intensive care patients because it has little anti-plaque action and extended use may result in a large amount being absorbed. ^[32]

Swabs of lemon and glycerol: Although the first action may stimulate salivary flow, excessive use may exhaust this mechanism, resulting in xerostomia. These swabs are no longer commonly utilised for providing dental care in intensive care patients due to an acidic and decalcifying effect on tooth enamel.^[2], ^[32]

Salivary substitutes are vital in maintaining the xerostomic patient's mouth moist. The salivary enzymes lactoferrin and lysozyme, which are crucial for strengthening the natural immunological process, must be included in the replacement. Intubated patients' lips are at a high risk of drying out and cracking.^[32] This is due to the patient's inability to naturally remoisten the lips by passing the tongue around the surface. To prevent lip dehydration, petroleum jelly and lanolin are utilized because they have an occlusive effect that inhibits transepidermal water loss.^[32]

Intubated patients can benefit from dental syringes([Figure 3]) with a curved nozzle for mouth rinses. A flexible suction catheter ([Figure 4]) is recommended for eliminating secretions accumulated above the endotracheal tube cuff because it can reach the subglottic area. To remove junk from the tongue, it is necessary to clean it. A forward-raking motion down the back of the tongue, especially with a small, soft-bristled toothbrush36, is used for this operation.^[32]