Glucometer Testing in the Dental Office

Q. What is a glucometer used for and how does it work?

A. A glucometer is a hand-held device used by patients to measure the amount of glucose (sugar) in their blood stream. The more conventional method of measuring glucose is through testing the blood drawn during a physician’s visit. The conventional method is not effective for people with diabetes because they need to know what their glucose levels are in a very short period of time and throughout the day. They can’t run to their physician’s office every time they need to check their blood sugar! Glucometers were developed to provide self-blood glucose monitoring or SBGM.

Glucometers measure the reaction between the glucose that’s in the blood stream and an enzyme, glucose oxidase, that catalyzes the oxidation of glucose. A strip that contains this enzyme goes into the meter and when glucose touches the enzyme, it morphs into a product that is easily measured. The product is then measured by the meter through an electrochemical cell within the device. When glucose binds to this enzyme, it oxidizes, creating an electrochemical reaction. The machine actually measures the change in electrical current through the strip.

THE DENTAL SETTING

Q. Are glucometers used in the dental office? If so, how often?

A. In a recent study that looked at how dental professionals treat patients with diabetes, the authors asked more than 100 general dentists and over a 100 periodontists how they managed patients with diabetes in their office.¹ They asked questions like “How often do you refer a patient for glucose level determination or monitor glucose levels yourself?” Approximately 14% of general practitioners and 28% of periodontists responded that they participated in proactive patient management activities like referring patients or monitoring glucose levels.

The use of glucometers in dental offices is uncommon. There are many reasons for this phenomenon but, more important, it is also unusual for patients to bring their glucometers to dental appointments. Dentists and dental hygienists should recommend that their patients with diabetes bring glucometers to the office.

Q. Why is the use of a glucometer in the dental office important?

A. The best way to avoid a low-blood sugar reaction in the dental office is to have the patient know what his or her blood sugar is before a procedure begins. If a patient starts a dental appointment with low blood sugar, then he or she may experience a problem with hypoglycemia (very low blood sugar) during the appointment. If blood sugar is normal or high, then the risk of a hypoglycemic reaction in the dental chair is much lower.

Q. How can dental professionals use the glucometer in their practices?

A. Dental professionals should not use a glucometer as a diagnostic tool for diabetes as they are not physicians. However, dental professionals should definitely use the glucometer to monitor patients before their dental treatment begins. I believe that monitoring blood sugar in the dental office in patients with diabetes should become much more routine. This will lower the risk of in-office hypoglycemic emergencies, especially for diabetic patients who use insulin.

THE GLUCOMETER AS A SCREENING TOOL

Q. Is it appropriate for dental professionals to use the glucometer as a screening tool?

A. It depends on what is being screened for. If a patient presents with oral symptoms of diabetes, then a dental professional can use the glucometer to check the patient’s blood sugar. But first, the dental professional should ask the patient questions relating to the classic signs and symptoms of diabetes. These include frequent urination, excessive thirst, excessive sense of hunger, or recent changes in vision. If in addition to the signs and symptoms of diabetes, the patient’s glucose level reading on the glucometer is very high (a normal glucose level range is between 70 and 100 mg/dl; a fasting glucose level over 125 mg/dl or a nonfasting glucose level of over 200 mg/dl is considered suggestive of diabetes), then the dental professional can advise the patient that he/she is exhibiting symptoms of diabetes and should see a physician for the appropriate tests as soon as possible. Screening is only valuable if the end result is to refer a patient to his/her physician for definitive diagnosis. Otherwise, the glucometer should not be used as a screening tool.

Glucometer testing is not approved by the American Diabetes Association as a diagnostic tool; it is not used to diagnose diabetes. Diagnosis of diabetes must be made based on blood samples examined in a medical laboratory.

Q. Why is glucometer testing not used as a diagnostic tool?

A. A glucometer is not definitive enough. Many people with type 2 diabetes have a normal blood sugar level in the morning after they fast. Their glucose rapidly increases and stays elevated after they eat. Just because a person has a normal glucose value reading on a glucometer does not mean that he or she does not have diabetes. If a dental professional sees signs and symptoms of diabetes but a glucometer reading is normal, the patient should still be referred to the physician for evaluation.

Q. When do you recommend glucometer testing?

A. I recommend glucometer testing for all of my diabetic patients before treatment begins. But it is particularly important for diabetic patients who take insulin as part of their management regimen because insulin is associated with the highest risk of hypoglycemia. As a periodontist, I spend a lot of time performing surgery and some of my cases are fairly long. My standard office protocol when performing a procedure on a patient with diabetes is to ask the patient to bring in his/her glucometer to the dental office and have the patient check his/her blood sugar before treatment begins. I then write down the glucometer reading in the chart. I always note that the number is a pretreatment glucose measurement taken with the patient’s own glucometer. If the glucose level is low or if I’m starting a 3-hour procedure and the glucose is even in the normal range, I usually give the patient a small amount of carbohydrate before I begin to increase the glucose level so he/she won’t become hypoglycemic during the procedure. I usually give 15 g of carbohydrate, which is about 4 oz to 6 oz of juice, depending on the juice. Grape juice is very concentrated with glucose whereas orange and apple are less so. About 15 g of carbohydrate will usually raise the glucose level by 30 g to 50 g per deciliter. This protocol is appropriate for any dental/dental hygiene procedure lasting more than 45 minutes to 1 hour, including scaling and root planing.

REFERENCE

1. Kunzel C, Lalla E, Lamster IB. Management of the patient who smokes and the diabetic patient in the dental office. J Periodontol. 2006;77:331-340.

From Dimensions of Dental Hygiene. September 2007;5(9): 16, 18.