Scientific discovery and technological innovations occur often, some of which impact the practice of dentistry. Sometimes the impact is obvious, sometimes it is less so. In March 2007 on the ACEsthetic e-mail dental network, I read about a potential complication for our patients with insulin pumps.

There are 2 types of diabetes. Patients with type 2 diabetes are insulin-resistant. Their cells have glucose and the pancreas makes insulin, but the cells resist the insulin and do not properly process the glucose.¹ Patients with type 1 diabetes are insulin-dependent. Their bodies destroy the insulin-producing cells in their pancreas. From the time of the diagnosis, patients with type 1 diabetes must inject insulin into the fatty layer under the skin using ultrafine needles. Some patients inject their thighs, some inject their belly fat. These patients calculate the amount of insulin to inject based on the amount of carbohydrates they ingest.²

Type 1 Diabetes Management

Patients with type 1 diabetes take 2 forms of insulin: long-acting, which helps keep blood sugars at acceptable levels for the entire day and compensate for small fluctuations throughout the day, and short-acting, which is injected after eating. Patients with type 1 diabetes often carry their equipment with them, and check their blood sugars frequently. They look for glucose numbers around 100 mg/dL, and try to attain a quarterly average blood glucose reading (glycated hemoglobin [Hb A_1c]) of 7%. A blood glucose reading <85 mg/dL is considered hypoglycemic and > 200 mg/dL is considered hyperglycemic.³

Figure 1—Infusion needle and canula placed in a patient with type 1 diabetes. The tube is connected to the pump.

One newer development in insulin delivery is the insulin pump. In the early days of the insulin pump (the early 1960s⁴), patients with diabetes wore a large box on their bodies that continually provided insulin. The adjustments were minimal. Once set, the pump constantly dripped insulin into the subcutaneous tissue and the patient was free from multiple injections. Today's insulin pumps are a little more complex, and yet easier to use.

The patient with diabetes who uses an insulin pump has insulin constantly coursing through their system, avoiding high or low glycemic episodes.⁵ The pump delivers the medication through a small tube and into a canula that is placed under the skin (Figure 1). Instead of 3 or more injections per day, the canula is placed about 12 times per month. A basal amount of insulin is delivered throughout the day and a bolus is programmed after meals to compensate for the increase of sugars. The pump is about the size of a deck of playing cards or even the size of a stack of business cards. The insulin is stored in the pump and must be refilled occasionally.

Figure 2—1960s insulin pump delivering glucagon and insulin.

After a patient with diabetes is adept at measuring glucose levels throughout the day and able to manage his or her blood sugars, the physician or diabetes educator may determine that the patient is eligible for an insulin pump. For the person with diabetes, there are a number of benefits to using an insulin pump. One is that there is just one needle placement every few days. Another, probably more important benefit, is that glycemic control is better.⁶ Patients who use an insulin pump have fewer hypoglycemic episodes, and their Hb A_1c level is closer to the coveted 7%. Complications of diabetes decrease in patients with tighter glycemic control, such as those who use insulin pumps.⁷

Size and the level of automation of the pumps have changed through the years (Figures 2 and 3). Today, electronic and bluetooth technology is used to communicate information to the delivery system from a handheld computer (Figure 4). The part that is attached to the body can send information to the PDA-sized computer, which calculates the amount of insulin that needs to be delivered and transmits that information back to the delivery system.

Checking blood glucose levels is managed by the handheld computer as well. The computer measures the blood glucose level, then the amount of carbohydrates consumed is entered into the computer by the patient, and the amount of insulin is calculated. (The insulin is measured as 1 unit for every 15 g of carbohydrates.) After calculating the amount of insulin needed, the computer displays the information. If it is correct, the patient presses a button and the delivery system delivers the bolus of insulin.

Figure 3—An insulin pump system with handheld wireless computer. The delivery device is preloaded with insulin for up to 3 days' treatment, and the computer manages the amount and time of insulin delivery (courtesy of Insulet Corporation).

Dental Implications

With new technologies come new complications, and this new type of delivery system has a direct impact on dental practice. One complication is that insulin pumps may be affected by radiation exposure. Medtronic Inc is putting the word out with an important safety information link on their Web site that their insulin pumps are highly affected by radiation, even the radiation that is delivered by dental x-ray units.⁸ When contacted, the customer service representative who answered the company's helpline assured me that if the devices are covered with a lead apron, dental professionals can safely take dental x-rays on patients wearing insulin pumps.

Figure 4—An insulin technology system that combines insulin pump therapy, blood glucose monitoring, personalized insulin pump programming, and data management (courtesy of Smiths Medical MD, Inc).

Most patients wear their insulin pumps on their torsos, so covering the devices with a protective apron is usually easy. Some people with diabetes wear their pumps on other parts of their bodies, perhaps a leg or love handle toward their back. It is best to ask patients with diabetes if they use a pump and where, specifically, it is located. If it won't be covered with the protective apron, it is best to ask them to remove it. Insulin pumps can be disconnected and reconnected in seconds, and placed outside the treatment room. Moving the devices to a location away from x-ray beams is just a precaution. According to Medtronics Inc, it is unknown what would happen if the device were hit with a beam of radiation at any level.

It is important to note that insulin is not the only medication delivered with pump technology. Some companies also have automated delivery systems for other drugs, such as pain medication. Any pump delivering any medication is susceptible to radiation and the same x-ray precautions should be taken.

Conclusion

Our patients with diabetes deserve the best possible treatment. The costs for surviving diabetes are high, and the costs of not maintaining glycemic health are even higher. Dental health care providers, through diligent treatment, can help keep those costs down by being aware of the potential dental-related complications.

Shirley Gutkowski, RDH, BSDH, is a popular international speaker, award-winning writer, and coauthor of The Purple Guide series with Amy Nieves, RDH. She invites you to visit her Web site, www.shirleygutkowskirdh.com, for an updated calendar of her speaking engagements.

References

1. Type 2 diabetes. American Diabetes Association Web site. Available at: www.diabetes.org/type-2-diabetes.jsp. Accessed Apr 17, 2007.
2. About insulin and other drugs. American Diabetes Association Web site. Available at: www.diabetes.org/type-1-diabetes/insulin.jsp. Accessed Apr 17, 2007.
3. Measures of kidney function. Life Options Web site. A service of the Medical Education Institute, Inc. Available at: www.lifeoptions.org/kidneyinfo/labvalues.php. Accessed Apr 18, 2007.
4. Beginnings. Medtronic MiniMed, Inc Web site. Available at: www.minimed.com/about/history.html. Accessed Mar 31, 2007.
5. Insulin delivery. Diabetes Forecast 2007 Resource Guide. American Diabetes Association Web site. Available at: www.diabetes.org/diabetes-forecast/RG07/RG07insulindelivery.pdf. Accessed Apr 17, 2007.
6. Rudolph JW, Hirsch IB. Assessment of therapy with continuous subcutaneous insulin infusion in an academic diabetes clinic. Endocr Pract. 2002;8:401-405.
7. Diabetes control and complications trial (DCCT). National Diabetes Information Clearinghouse, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health Web site. Available at: diabetes.niddk.nih.gov/dm/pubs/control/index.htm. Accessed Apr 3, 2007.
8. Medtronic MiniMed, Inc. Important safety information [press release]. Available at: www.minimed.com/about/safety.html Accessed Apr 18, 2007