17: Human Diseases and Health Promotion

The severity of an illness

The severity of an illness can influence the type of operation or other medical care given, since in very ill patients such interference can cause the patient to deteriorate.

A commonly used system to classify the severity of illnesses is the American Society of Anesthesiologists’ (ASA) system, shown in Table 17.1.1.

TABLE 17.1.1 ASA Classification of State of Health

Class I	Normal healthy individual
Class II	Patient with mild systemic disease (not interfering with daily life)
Class III	Severe systemic disease (interferes with daily life)
Class IV	Incapacitating systemic disease (constant threat to life)
Class V	Moribund (very seriously ill) patient with life expectancy <24 hours

Oral healthcare in ill patients

• It is generally accepted that the least operative work done should be aimed for.

• All patients with medical conditions benefit from preventive dental care:

Practising good oral hygiene

Regular dental examinations

Dietary counselling

Use of fluorides to minimise the risk of developing caries.

Term to Learn

Mutation: alteration in the DNA sequence of a cell’s genome (the full DNA sequence of an organism), which can have several causes such as exposure to radiation, certain viruses and chemicals.

Key point

People, particularly those who are ill, often have concerns about privacy, and about the social implications of their condition. You must therefore strictly adhere to data protection and patient confidentiality principles. Reassure the patient that none of their details will be discussed, even with partners, unless permission is gained from them.

Alcoholism

Alcohol is the most commonly misused drug. It affects the functioning of the central nervous system (CNS) as follows:

• Interfering with the cerebral cortex to release inhibitions

• Impairing the capacity to reason

• Interfering with the functioning of the cerebellum (see Chapter 4) to cause unsteadiness of gait (ataxia) and inco-ordination of movements.

Term to Learn

Release of inhibitions: when people start acting in ways or saying things they would not normally do (thus serious people start giggling, etc.).

Eventually alcoholism interferes with the working of the brain centres (e.g. respiratory) and can cause unconsciousness or even death (Table 17.1.2). The high rate of deaths among people with alcoholism is mainly as a result of road traffic accidents and assaults. Alcoholics can also drown in their own vomit.

TABLE 17.1.2 Acute Effects of Alcohol

Alcohol and the Six Ls

Social difficulties from alcohol misuse are common and can affect the six ‘Ls’:

• Law – breach of the criminal, civil and/or professional codes

• Learning – intellectual difficulties

• Livelihood – job problems

• Living – housing problems

• Lover – relationship difficulties of all kinds: husband/wife; partner, employer/employee, etc.

• Lucre – (Latin lucrum = wealth) money problems.

Many other diseases can be caused or aggravated by alcohol including:

• Bleeding tendency

• Brain damage and epilepsy

• Cancers

• Gastro-intestinal disease

• Heart disease

• Impaired wound healing

• Infections, especially pneumonia and tuberculosis

• Injuries (including maxillo-facial), from accidents or assaults

• Liver disease

• Malnutrition

• Muscle disease

• Pancreatic disease.

Management

Alcoholic people need help in the way of admission to a rehabilitation unit. Management includes ensuring abstinence, adequate nutrition and medication to reduce dependence.

Allergy

Allergy is an abnormal response to an allergen (protein). Potential allergens in dentistry are:

• Latex – the most common cause (see Chapter 12 for more details)

• Anti-microbial drugs (e.g. penicillin).

Rare allergic reactions in dentistry occur in relation to:

• Local anaesthetics (LAs)

• Oral healthcare products (antiseptics, mouthwashes, oils such as eugenol)

• Dental materials (impression materials, cements, adhesives, resins, metals)

• Disinfectants.

Common allergens are listed in Table 17.1.3.

TABLE 17.1.3 Common Allergens

Allergen Source	Examples
Dental materials	Amalgam, gold, mercury, resins, plasters (e.g. Elastoplast)
Drugs	Aspirin, penicillins
Environment	Animal hair, dust mites, pollens
Foods	Milk, nuts (especially peanuts), eggs, shellfish
Latex	Gloves, dressings, elastic bands, condoms

Allergies are responsible for some types of the following diseases and conditions:

• Asthma

• Eczema

• Rhinitis (hayfever)

• Anaphylaxis (collapse, with low blood pressure and breathing difficulties) – this can be fatal (Chapter 2).

Key Points

People at risk of anaphylaxis should carry an Epipen (syringe containing adrenaline) for self-administration.

As a dental professional, you must be familiar with the medical management of anaphylaxis within a dental setting (see Chapter 2).

Early Symptoms and Signs of an Allergic Reaction

These include:

• Breathlessness and itchy rash (hives or urticaria), which typically occur within a few minutes to an hour

• Wheezing (bronchospasm).

• Fall in blood pressure (hypotension)

• Swelling of the face and lips (angio-oedema; Figure 17.1.2) and laryngopharynx. This may be followed by life-threatening anaphylactic shock.

FIGURE 17.1.2 Angio-oedema.

Anaemia

A person is said to have anaemia when their haemoglobin (Hb) level is below the normal for their age, gender and ethnic background. Haemoglobin is required to carry oxygen to the brain and tissues (see Chapter 4). Anaemia has many causes as shown in Table 17.1.4.

TABLE 17.1.4 Causes of Anaemia

Nature of Anaemia	Cause
Increased loss of red blood cells (RBCs)	Menstrual blood loss
	Gastro-intestinal blood loss
	Haemolysis (breakdown of the RBCs), such as in malaria or sickle disease
Reduced RBC production	Dietary deficiency
Reduced RBC production	Bone marrow disease, such as in leukaemia
Increased tissue requirements	Puberty
Increased tissue requirements	Pregnancy
Decreased tissue requirements	Hypothyroidism

Anaemia may not cause any symptoms early on. But, as it worsens and the oxygen-carrying capacity of the blood falls, symptoms and signs develop (e.g. breathlessness, palpitations).

Key point

Pallor of the oral mucosa, conjunctiva or palmar creases suggests severe anaemia.

Management

Management includes treatment of the underlying cause. Deficiency states must be corrected with iron, folic acid, and vitamin B12 supplements. Blood transfusion may be indicated if the onset of anaemia has been rapid.

Anti-coagulant-related problems

Anti-coagulants are drugs used to slow blood clotting. This is required to control and prevent clotting in people who have deep vein thromboses (thrombo-embolic disorders) or after heart surgery. The dose of the drug needs to be controlled or the patient will bleed too easily. Warfarin is the most frequently prescribed anti-coagulant. The dose is controlled by doing a blood test called the international normalised ratio (INR). An INR above 1 indicates that clotting will take longer than normal.

Term to Learn

Thrombo-embolic disorder: a disorder related to the formation of blood clots (thrombi) in one part of the body, of which either small portions or the whole clot can then become loose (emboli) and travel to other parts of the body in the blood stream, causing e.g. pulmonary thrombosis.

Surgery is the main hazard for the patient on warfarin. Thus alternative treatments, e.g. endodontic treatment, are always considered.

Dental Considerations

Key Point

Anti-coagulant doses should not be altered without consulting the doctor in charge. Stopping the drug before surgery is dangerous as there can be fatal thromboses (blood clots).

LA regional block injections, or those given in the floor of the mouth, may be a hazard since bleeding into the tissues of the neck can block the airway and suffocate the patient. If surgery is to be more than simple or minor, or the INR is above 3.5, the patient is usually treated in hospital or another specialist centre.

Aspirin and non-steroidal anti-inflammatory agents (NSAIDs) inhibit platelet aggregation and cause bleeding. Thus they should be avoided in these patients. Paracetamol is the analgesic of choice for these patients.

Anxiety and stress

Anxiety is an unpleasant emotional state characterised by fear and a variety of physical symptoms. Stress raises blood levels of the adrenal hormones: cortisol, adrenaline (epinephrine) and noradrenaline (norepinephrine). These ‘stress hormones’ influence many physiological functions, causing:

• Apprehension

• Fast pulse rate (tachycardia)

• Over-breathing (hyperventilation)

• Raised blood pressure (hypertension)

• Sweating

• Tremor

• Dilated pupils

• Involuntary defecation

• Urinary incontinence.

Types of Anxiety Disorders

• Panic disorder: the person panics apparently spontaneously

• Phobia: the anxiety is provoked by discrete stimuli, e.g. phobia of flying or dental treatment.

• Generalised anxiety disorder: such people worry all the time.

Management

• Appropriate management of any underlying organic disease.

• Lifestyle changes to reduce stressors and avoid precipitating factors.

• Behavioural therapies that aim to change anxiety-provoking behaviours (e.g. talking treatments such as cognitive behaviour therapy (CBT)).

• Drugs (anxiolytics such as diazepam or beta-blockers).

• Psychotherapy.

Arthritis

Osteoarthritis (OA)

This is the most common type of arthritis, and consists of progressively worsening joint deformity. Risk factors for OA include:

• Age over 45 years

• Gender: females are more commonly affected

• Genetic predisposition

• Obesity

• Malformed joints (hereditary or acquired)

• Trauma

• Occupation (athletes).

Osteoarthritis may affect any joint, but frequently used, weight-bearing or traumatised joints such as those in the fingers, hips, knees, lower back and feet are more often affected.

Symptoms and signs

Joint pain, stiffness, deformity, loss of flexibility and reduced function.

Asthma

Asthma is a common condition in which there is difficulty breathing because of narrowing of the airways. This can happen because of:

• Excessive tone of the muscles in the walls of the bronchi (bronchospasm)

• Oedema

• Hypersecretion of mucus.

During an asthmatic attack a person may have difficulty breathing, cough and wheeziness.

There are two types of asthma (Table 17.1.5): extrinsic and intrinsic. Extrinsic asthma is more common and is caused by exposure to allergens. Intrinsic asthma is much less common and is often not related to exposure to allergens.

TABLE 17.1.5 Types of Asthma

	Extrinsic	Intrinsic
Frequency	Common	Less common
Associations	Allergic disease (hay fever, eczema, allergic rhinitis)	None
Main precipitating factors	Animal hairs	Air pollutants
	House dust mite	Cold air
	Pollen and moulds	Drugs (NSAIDs)
		Stress
		Exercise

Management

This includes drug treatment, smoking cessation and avoidance of precipitants.

A prolonged asthmatic attack which is resistant to treatment may lead to life-threatening status asthmaticus.

Atheroma (atherosclerosis)

Atheroma is the accumulation of fats (cholesterol and lipids) in the artery walls. The accumulation occurs in the form of plaques. These can cause narrowing of the arteries and reduce the blood supply to the tissues supplied by that artery.

Autism

Autism is a developmental disorder that usually begins in the first 30 months of life. It is characterised by:

• Poor social skills – inability to get along with people

• Lack of developing interpersonal relationships – people with autism appear indifferent and remote. They are unable to form emotional bonds with others, or understand other people’s thoughts, feelings, and needs. They seem to prefer being alone, and may resist attention and affection or passively accept hugs and cuddling.

• Abnormal speech and language – specialised educational help is required.

• Ritualistic or compulsive behaviour with repetitive stereotyped activities – most autistic people have an obsessional desire for maintaining an unchanging environment and rigidly following familiar patterns in their everyday routines.

Asperger’s is a related syndrome.

Bell’s palsy

Bell’s palsy (Figure 17.1.5) is a type of facial paralysis that usually occurs on one side. It occurs mainly due to infection with herpes simplex virus (HSV). Most patients recover totally and spontaneously within a few weeks. Treatment includes:

• Anti-inflammatory medication

• Antiviral medication.