When a person has diabetes, the raised blood sugar can affect many parts of the body, including our mouth and teeth. Diabetes increases the risk of gum disease, dry mouth, caries (tooth decay) and a variety of oral infections.

Although further studies are needed, it appears that poor oral health can make diabetes more difficult to control. Bacteraemia resulting from gum disease may cause the release of inflammatory mediators, which interfere with lipid metabolism and increase insulin resistance.

Diabetes can also make it harder to control the sweet tooth. This is because diabetes can reduce the ability to taste sweetness. Although this change may not be noticeable, it can cause the person to crave sweeter foods, thereby affecting control of the diabetes and dental health.

On the other hand, people with diabetes who control their blood glucose well have no more dental problems than the rest of the population. Preventive dental care must form part of the total care for patients with diabetes. Rigorous oral hygiene can prevent the following oral complications:
 

Gum disease

Periodontal (gum) disease is the most common oral complications of diabetes. Patients with poorly controlled diabetes are at greater risk of developing gum disease.

The reason for the higher prevalence of gum disease in diabetic patients is not known. Studies have found no difference in the periodontal microbial flora in people with or without diabetes, suggesting that the gum destruction in diabetes could be due to altered host response. For example, in diabetic patients, cell-mediated immunity such as neutrophil chemotaxis and macrophage function may be impaired.

In diabetes, the glucose level in the saliva and gingival crevicular fluid are also raised. Increased salivary glucose (salivary hyperglycaemia) may be an important contributing factor to gum disease by increasing the formation of bacterial plaque in the mouth.

Dry mouth

Diabetes can cause xerostomia (dry mouth). The cause is unknown but may be related to polyuria or alterations in the basement membranes of salivary glands. Dry mouth makes the wearing of dentures difficult and irritating.

Dryness of mouth also makes the teeth susceptible to dental decay. The buffering and cleansing actions of saliva protects the dental tissues from tooth decay. Topical treatments such as fluoride-containing mouthwash and salivary substitutes can provide relief.

Oral infection

Diabetes is also associated with oral infection such as candidiasis (thrush) and lichen planus. Candida albicans is a fungus that normally lives inside the mouth without causing any problems. In diabetes, reduced salivary flow and extra sugar in the saliva enable the fungus to cause an infection called candidiasis, which appears as sore areas in the mouth.

Oral lichen planus is a skin disorder.  When severe, it causes painful ulcers and sores in the mouth. Dry mouth and candidiasis can cause a burning pain in the mouth. Treating the dryness and fungal infection can alleviate the symptoms.

Caring for your teeth and gum

Prevention is the best medicine. A diabetic patient should floss and brush every day and visit the dentist at least twice yearly. It is important that the attending dentist knows that a patient has diabetes. A thorough understanding of the patient's diabetes treatment including types of medication, regimen, degree of glycaemic control and any systemic complications needs to be established. The patient's physician is a partner in dental care delivery. The dentist will consult with the patient's physician to discuss dental treatment plan, especially when surgical procedures are involved.

Morning appointment is best for diabetic patients. This is a time of high glucose and low-insulin activity. The physiological rise in blood glucose in the morning plus breakfast and morning medication make the morning hours the recommended time for diabetic patients to receive dental treatment. As far as possible, the dental appointment should be kept short.

Afternoon appointments are usually a time of low-glucose and high-insulin activity which may predispose patients to hypoglycaemic reaction. Patient should inform the dentist if during the appointment they feel unwell. A serving of hot chocolate, fruit juice or small snacks is usually available in the dental clinic and sufficient to restore the blood glucose level.

The patient with diabetes who is receiving medical care and maintains good glycaemic control can receive dental treatment similar to patients without diabetes. They do not require antibiotic prophylaxis unless it is absolutely necessary such as in acute oral infection. Like anyone else, a person with well-controlled diabetes can enjoy good oral health.

References
1. George W Taylor. The effect of periodontal treatment on diabetes. Journal of American Dental Association 2003:134: 41-48.

2. Stolbova K, Hahn A, Benes B, Andel M, Treslova L. Gustometry of diabetes mellitus patients and obese patients. Int Tinnitus J 1999:5(2): 135-40.

3. Genco RJ, Van Dyke TE, Levine MJ, Nelson RD, Wilson ME. 1985 Kreshover lecture: molecular factors influencing neutrophil defects in periodontal disease. J Den Res 1986: 65:1379-91.

4. Touger-Decker R, Sirois DA. Dental care and patients with diabetes. In: Powers MA, ed. Handbook of diabetes medical nutrition therapy. Gaithersburg, Md.: Aspen Publishhers: 1996:638-48.

5. Campbell MJ, Glucose in the saliva of the non-diabetic and the diabetic patient. Arch Oral Biol 1965:10:97-205.

6. Field EA, Longman LP, Bucknall R, Kaye SB, Higham SM, Edgar WM. The establishment of a xerostomia clinic: a prospective study. Br J Oral Maxillofac Surg 1997: 35(2):96- 103.