Diabetes Mellitus

Definition:

A group of metabolic diseases in which a person has high blood sugar , either because the body does not produce enough insulin , or because cells do not respond to the insulin that is produced.

Epidemiology:

The prevalence of diabetes is expected to double between 1994 and 2010, at which time about 240 million people will have the disease. In general, the incidence of diabetes rises as the population ages and as the prevalence of obesity increases.

Classification:

• Type 1 (insulin-dependent diabetes; juvenile diabetes)
• Type 2 (non-insulin-dependent diabetes; adult-onset diabetes)
• Gestational diabetes (pregnancy diabetes)
• Other forms of diabetes mellitus include congenital diabetes, which is due to genetic defects of insulin secretion, cystic fibrosis-related diabetes, steroid diabetes induced by high doses of glucocorticoids, and several forms of monogenic diabetes.

Acute complications:

• hypoglycemia
• diabetic ketoacidosis
• nonketotic hyperosmolar coma

Serious long-term complications:

• cardiovascular disease
• chronic renal failure
• retinal damage

Type 1 Diabetes Mellitus

- It is characterized by loss of the insulin-producing beta cells of the islets of Langerhans in the pancreas leading to insulin deficiency.

- This type of diabetes can be further classified as immune-mediated or idiopathic. The majority of type 1 diabetes is of the immune-mediated nature, where beta cell loss is a T-cell mediated autoimmune attack.

- It can affect children or adults but was traditionally termed "juvenile diabetes" because it represents a majority of the diabetes cases in children.

- People with type 1 diabetes are highly susceptible to diabetic ketoacidosis. Because the pancreas produces no insulin, glucose cannot enter cells and remains in the bloodstream. To meet cellular energy needs, fat is broken down through lipolysis, releasing glycerol and free fatty acids.

- There will be increase in ketone levels in body fluids and increase hydrogen ion concentration ( decrease in pH) resulting in diabetic ketoacidosis (DKA). Untreated DKA can result in coma or death.

Type 2 Diabetes Mellitus

- It is the most common type , characterized by insulin resistance which may be combined with relatively reduced insulin secretion.

- The defective responsiveness of body tissues to insulin is believed to involve the insulin receptor. However, the specific defects are not known.

- In the early stage of type 2 diabetes, the predominant abnormality is reduced insulin sensitivity. At this stage hyperglycemia can be reversed by a variety of measures and medications that improve insulin sensitivity or reduce glucose production by the liver .

- Most type 2 diabetes patients are overweight, and most are diagnosed as adults.

- In addition to genetic influences, acquired risk factors for type 2 diabetes include obesity, advancing age, and an inactive lifestyle.

- It is characterized by the following three disorders:

(1) Peripheral resistance to insulin, especially in muscle cells.

(2) Increased production of glucose by the liver.

(3)Altered pancreatic insulin secretion

Gestational Diabetes Mellitus (GDM)

- It develops during the third trimester and significantly increases perinatal morbidity and mortality.

- Resembles type 2 diabetes in several respects, involving a combination of relatively inadequate insulin secretion and responsiveness.

- It occurs in about 2%–5% of all pregnancies and may improve or disappear after delivery.

- Gestational diabetes is fully treatable but requires careful medical supervision throughout the pregnancy.

- About 20%–50% of affected women develop type 2 diabetes later in life.

- Even though it may be transient, untreated gestational diabetes can seious effect on the health of the fetus or mother. Risks to the baby include macrosomia (high birth weight), congenital cardiac and central nervous system anomalies, and skeletal muscle malformations.

- Increased fetal insulin may inhibit fetal surfactant production and cause respiratory distress syndrome.

- Hyperbilirubinemia may result from red blood cell destruction.

Signs and Symptoms of DM

• Polydipsia (excessive thirst)
• Polyuria (excessive urination)
• Polyphagia (excessive hunger)
• Unexplained weight loss
• Changes in vision
• Weakness, malaise
• Irritability
• Nausea
• Dry mouth
• Ketoacidosis, usually associated with severe hyperglycemia and occurs primarily in type 1 diabetes

Diagnosis

• Presence of diabetes symptoms plus random (nonfasting) plasma glucose ≥ 8.4 mmol/L (200 mg/dL) random glucose may be drawn at any time of day without regard to time since last meal.
• Fasting plasma glucose ≥ 7 mmol/L (126 mg/dL) fasting is defined as no caloric intake for at least 8 hours.
• Two-hour postprandial glucose ≥ 8.4 mmol/L (200 mg/dL) during an oral glucose tolerance test‡ using a glucose load containing the equivalent of 75 g of anhydrous glucose dissolved in water.

Diabetes and Oral Health

• burning mouth
• altered wound healing
• increased incidence of infection
• enlargement of the parotid glands and xerostomia can occur; this may be related to the metabolic control of the diabetic state

Periodontal Health and Diabetes

- Differences in host response may increase the prevalence and severity of periodontal destruction seen in patients with diabetes.

- Hyperglycemia results in increased gingival crevicular fluid glucose levels, which may significantly alter periodontal wound-healing events by changing the interaction between cells and their extracellular matrix within the periodontium.

- Vascular changes occur in the periodontium.

- The formation of Advanced glycation end products (AGEs) results in collagen accumulation in the periodontal capillary and stimulate smooth-muscle proliferation leading to increase of the thickness of vessel walls.

- These changes decrease tissue perfusion and oxygenation. Blood vessel walls binds circulating LDL, which is frequently elevated in diabetes, resulting in further narrowing of the vessel lumen.

- These changes in the periodontium may dramatically alter the tissue response to periodontal pathogens, resulting in increased tissue destruction and diminished repair potential.

- Diabetes results in changes in the function of host defense cells such as polymorphonuclear leukocytes (PMNs), monocytes, and macrophages.

- These host defense alterations cause an increase in periodontal inflammation, attachment loss, and bone loss.

Effects of Peridontal Infection on Glycemic Control

- Periodontal infection increased the risk of poor glycemic control by sixfold.

- Periodontitis is also associated with an increased risk for other diabetic complications, such as nephropathy and macrovascular disease.

Dental Management of the Diabetic Patient

• Oral hygiene
• Diet
• Habits such as tobacco use
• Proper dental care and follow-up
• Overall oral health
• Metabolic control of diabetes.
• Stress reduction
• Treatment setting
• The use of antibiotics
• Appointment timing
• Changes in medication regimens
• Management of emergencies