Wearing barriers and washing our hands can protect patients from our microbes

Nov. 1, 1998
Last month we discussed the first of five pathways by which microbes may be spread in a dental office:

Chris Miller, PHD

Last month we discussed the first of five pathways by which microbes may be spread in a dental office:

(1) Patient to dental team

(2) Dental team to patient

(3) Patient to patient

(4) Office to patient

(5) Community to office

In this continuing series of articles, we`ll discuss the second pathway, spread from the dental team to a patient. As with patient-to-dental-team spread, microbes still must escape from their source, spread to a new host, enter that host, survive and multiply in the new host and cause damage to tissues to complete the infectious disease process. The difference is the source of the microbes.

Spread of microbes from the dental team to patients is rare, but has happened. A member of the dental team serves as the source of microbes that are transferred to the patient. One source is blood or tissue fluid that exits through lesions, unnoticeable cuts, or injury sites on the hands. If microbes are in the body fluids that "leak out," then the potential for spread occurs if direct contact is made with the patient`s oral tissues.

The direct contact occurs if gloves are not worn or if a sharps injury results in penetration of the gloves with immediate bleeding onto the patient`s tissues. Indirect contact could occur if body fluid from a dental team member contaminates an object that is subsequently used in the patient`s mouth.

Hepatitis B apparently has been spread from dentists to patients in 11 instances reported in the late 1970s and early 1980s. Two conditions help explain what may have happened in these 11 cases. However, looking back to try to explain how a disease was spread (retrospective analysis) seldom produces conclusive evidence. Apparently all 11 dentists involved were HBeAg-positive. This e-antigen is present when the hepatitis B virus is rapidly replicating, producing high levels of the virus in the body. Persons who are HBeAg-positive can have 100,000,000 hepatitis B viruses in each mL of their blood! Thus, these practitioners were highly infectious. Only very small amounts of their blood or tissue fluid were needed to transfer enough viruses to infect their patients.

Another condition was that these dentists did not routinely wear gloves when treating their patients. Thus, small amounts of highly infectious tissue fluids could have "leaked out" of naturally occurring invisible breaks in the skin of their ungloved hands and directly contacted patients.

In one of these instances, a dentist who did not routinely wear gloves, infected 55 patients with hepatitis B. After learning of the problem, he began routinely gloving and only two more cases of hepatitis B occurred among 4,300 patients seen. Of course, he may have made other important changes as well. Nevertheless, gloves, as well as masks and eyeglasses, serve as barriers to direct contact with potentially infectious materials.

All 11 of these hepatitis B cases occurred between 1972 and 1984, just before infection control in dentistry was re-emphasized in the mid-1980s. Since then, no such cases in dentistry have been reported.

Another aspect that influences whether patients become infected by health-care workers is the extent to which the health-care workers are infected with diseases that can be transferred during patient care. In the case of hepatitis B, fewer and fewer health-care workers are becoming infected, so this reduces the chances for spread to patients. Since 1985, there has been a 90 percent decrease in the number of health-care workers who acquire hepatitis B annually. The hepatitis B vaccine first became available to the public in 1982.

Members of the dental team may spread their respiratory microbes to patients through droplet infection (when a mask is not worn) or through contaminated hands or gloves. If a hygienist?s hands become contaminated with her or his respiratory (oral/nasal) fluids and those hands subsequently contact the patient?s mouth or items used in the patient?s mouth, microbial spread can occur. As discussed before, the hands commonly spread respiratory viruses, such as those that cause the common cold.

Chris Miller is director of Infection Control Research and Services and professor of oral biology at Indiana University.

Suggestions for choosing gloves

Exam gloves provide essential barrier protection to hygienists day in and day out. Without them, dental professionals are put at a significant health risk. Yet other priorities during the day make the brand selection of gloves more or less an afterthought.

Dental hygienists may wear up to 40 pairs of gloves in a day. By the end of a day, hands can be fatigued, possibly causing cramping. Suddenly, performing exacting procedures becomes more difficult, and results of the work may be less satisfying.

Here are a few thoughts to consider when deciding which gloves to order the next time your supply runs low.

Low protein content. The Food and Drug Administration has suggested that lowering protein levels in gloves will significantly reduce the risk and incidence of problems associated with latex sensitivity. As a result, many glove manufacturers are improving processes to ensure lower protein content.

Despite the many statements about protein levels made by glove manufacturers, the only claim you can trust is the one that is printed on the box. Furthermore, any claims printed on the box must have been approved by the FDA after strict testing has been conducted by the glove maker.

"We`ve taken our cue from the FDA to establish improved manufacturing processes which will help us greatly lower the water-extractable protein levels in our light-powdered and powder-free gloves," says Bob Sullivan Jr., president of Dash Medical Gloves.

Powder, powder-free, or synthetic. Many users prefer light-powdered gloves because they are easier to put on and take off, especially when their hands are wet from washing them between patient visits. Others opt for powder-free gloves because of concerns over protein content. Some manufacturers, though, have shown that protein levels in powdered gloves can be reduced down near the level of powder-free gloves.

A proper fit. Poor-fitting gloves, especially when too small, tend to draw the muscles of the hand inward - causing resistance against movement. As a result, your ability to perform exacting procedures in tight areas can be hindered. This can also cause fatigue by the end of a week, even the end of a day.

So, look for a glove which is most closely fitted to your hand size. Most manufacturers produce gloves ranging in three or four sizes. some may offer as many as six sizes. Naturally, more sizes offered means a better change of finding a glove that will best suit your needs.

Consistent performance. As a dental hygienist, you don as many as 200 gloves a week. Look for those that are consistently sized and, in the case of light-powdered gloves, evenly coated. If you pull a size six out of the box, the next pair out of that box should fit like a size six, too. The resistance to hand movement should be minimal, and it should feel the same - every time.

Powered gloves should also provide a comfortable, even feel. Don`t accept clumps of powder in the fingertips. This is not only a nuisance, but can also cause annoying delays as you take several minutes to wash your hands and don another pair of gloves. Try several different brands of gloves to compare.

Savings in ordering. Most exam gloves range in price from $4.50 to $8 for a box of 100 - depending on the quality and type of the glove. Savings can be realized many times by ordering direct from a manufacturer or ordering in larger quantities.

This information is provided by Dash Medical Gloves.