by Leslie Canham, CDA, RDA

How proper washing helps keep your practice clean

As dental professionals, we recognize that the first step in infection control is hand hygiene. Failure to perform appropriate hand hygiene is considered one of the leading causes of health care-associated infections and has been recognized as a substantial contributor to outbreaks. However, frequent and repeated use of hand hygiene products, particularly soaps and other detergents, is a primary cause of chronic irritant contact dermatitis among health care workers.1 Discomfort due to irritation can interfere with adherence to recommended hand hygiene practices.

The First Defense

The primary defense against infection and transmission of pathogens is healthy, unbroken skin.2 Intact skin also helps to prevent disease transmission to dental health care workers. Lotions are often recommended to ease the dryness resulting from frequent hand washing. However, petroleum-based lotion formulations can weaken latex gloves and increase permeability. For that reason, lotions that contain petroleum or other oil emollients should only be used at the end of the work day.2

Leslie Canham, CDA, RDA

Unfortunately, the hands of dental professionals are subject to a variety of occupational irritants including repeated use of hand hygiene products, exposure to chemicals, and glove use. As a result, contact dermatitis may occur and cause skin to break down.

Contact dermatitis is classified as either irritant or allergic. Irritant contact dermatitis develops as dry, itchy, irritated areas on the skin around the area of contact. By comparison, allergic contact dermatitis (otherwise known as type IV hypersensitivity) can result from exposure to accelerators and other chemicals used in the manufacture of rubber gloves, as well as from other chemicals such as methacrylates and glutaraldehyde that are found in the dental practice setting. Allergic contact dermatitis often manifests as a rash beginning hours after contact and, similar to irritant dermatitis, is usually confined to the area of contact.2

A History of Handwashing

Handwashing with an antiseptic agent was first introduced in the early 19th century by a French pharmacist who demonstrated that washing with solutions containing chlorides of lime or soda could eradicate the foul orders associated with human corpses and that such solutions could be used as disinfectants and antiseptics.

In 1961, the US Public Health Service produced the first training film on handwashing techniques. The film directed health care workers to wash their hands with soap and water for 1 to 2 minutes before and after patient contact.

Irritant contact dermatitis is a nonallergic reaction caused by chemical compounds or mechanical friction.
Photo courtesy SmartPractice

In 1975 and then again in 1985, the Centers for Disease Control and Prevention (CDC) issued written guidelines for handwashing practices in hospitals. The guidelines recommended handwashing with plain soap between the majority of patient contacts and washing with antimicrobial soap before and after performing invasive procedures or caring for patients at high risk. Use of waterless antiseptic agents (alcohol-based solutions) was recommended only in situations where sinks were not available.1

Bacteria on Hands

The skin on our hands is colonized with bacteria. The bacteria is divided into two categories: transient flora and resident flora.

Transient flora, considered the contaminating flora, are most likely to be associated with infection. Transient flora are easily removed by handwashing.

Resident flora, attached to the deeper layers of the skin, are more difficult to remove, but less likely to be associated with infection.

Hand Hygiene Products and Practices

There are many different hand hygiene methods. The preferred one depends on the type of procedure, the degree of contamination, and the desired persistence of antimicrobial action on the skin. For routine dental examinations and nonsurgical procedures, handwashing and hand antisepsis can be achieved by using either a plain or antimicrobial soap and water. If the hands are not visibly soiled, an alcohol-based hand rub is adequate.

Plain soaps are detergent-based products that can remove dirt, soil, and other organic materials from the hands. Plain soap and water can remove transient flora from the hands but have minimal antimicrobial activity.

Effective handwashing includes wetting hands and applying soap or an antimicrobial/antiseptic agent. The next step involves vigorously rubbing hands together to create a lather covering all the surfaces of the palms, tops of the hands, between the fingers, the base of the fingers and thumbs, the backs of the fingers, the wrists and fingernails, and then rinsing hands thoroughly to remove all the lather. Washing and rinsing should be performed with cool water, since hot water can be drying to skin. Handwashing should take at least 15 seconds.

Allergic contact dermatitis is a delayed Type IV allergic response, which means that it often manifests as a rash beginning hours after contact. Photo courtesy SmartPractice

The amount of time spent washing hands is important to reduce the transmission of pathogens to other people and environmental surfaces. Drying hands thoroughly is also important. Wet hands have been known to transfer pathogens much more readily than dry hands or hands not washed at all. The residual moisture determines the level of bacterial and viral transfer following handwashing.3

Antiseptic handwashing uses water and an antimicrobial soap. Antimicrobial soaps may contain chlorhexidine, iodine and iodophors, chloroxylenol, or triclosan. The purpose of an antiseptic handwash is to remove or destroy transient microorganisms and reduce resident flora.

Antiseptic hand rubs are waterless, alcohol-based products that include antiseptics such as chlorhexidine, quaternary ammonium compounds, octenidine, or triclosan. The antimicrobial activity of alcohols can be attributed to their ability to denature proteins. Alcohol solutions containing 60% to 95% alcohol are most effective. Higher concentrations are less potent because proteins are not denatured easily in the absence of water.1 Alcohols are rapidly germicidal when applied to the skin but are not appropriate for use when hands are visibly soiled or contaminated with proteinaceous materials.

The purpose of surgical hand antisepsis is to eliminate transient flora and reduce resident flora for the duration of a procedure to prevent the introduction of organisms in the operative wound if gloves become punctured or torn. Skin bacteria can rapidly multiply under surgical gloves if hands are washed with soap that is not antimicrobial. Surgical antisepsis is performed with water and antimicrobial soap or water and plain soap followed by an alcohol-based surgical handscrub with persistent activity. Agents used for surgical hand antisepsis should substantially reduce microorganisms on intact skin, contain a nonirritating antimicrobial preparation, have a broad spectrum of activity, be fast-acting, and have a persistent effect. Persistent activity is critical because microorganisms can colonize on hands in the moist environment underneath gloves.2

Type I latex allergy is an allergic response to the latex that is found in many treatment gloves.
Photo courtesy SmartPractice

Fingernails and Jewelry

To facilitate better handwashing and easier donning of gloves, fingernails should be no longer than 1/4 inch from the nail bed. Artificial nails have been implicated in multiple outbreaks involving fungal and bacterial infections. Freshly applied nail polish on natural nails does not increase the microbial load from periungual skin if fingernails are short; however, chipped nail polish can harbor added bacteria.2 Rather than using nail polish, it is best to buff nails to maintain a smooth surface because even chipped nail polish can harbor added bacteria.

Wearing jewelry such as rings can make effective hand hygiene more difficult. Several studies have demonstrated that skin underneath rings is more heavily colonized than comparable areas of skin on fingers without rings. One study found that 40% of nurses harbored gram-negative bacilli on skin under rings and that certain nurses carried the same organism under their rings for several months.1


Dental professionals have an obligation to prevent the spread of health care-associated infections. Adhering to proper hand hygiene procedures, selecting appropriate hand hygiene products, and the use of gloves are important for patient protection.

In addition, dental professionals must also protect themselves by recognizing pitfalls such as irritants or allergies that may pose obstacles to proper hand hygiene. Occupational irritants and allergies can be caused by frequent handwashing, exposure to hand hygiene products, exposure to chemicals, and shear forces associated with wearing or removing gloves.

Steps to ensure that skin remains healthy and intact include the evaluation and selection of hand hygiene products, gloves, and lotions for the best compatibility. If you see a breakdown of the skin barrier, you should take steps to determine the cause and remedy. If contact dermatitis or latex sensitivity are suspected, seek a diagnosis from a qualified medical practitioner.

Leslie Canham, CDA, RDA, has been in the dental field since 1971. She is a certified and registered dental assistant, and a speaker and consultant on infection control and OSHA compliance. She is authorized by the Department of Labor as an OSHA outreach trainer. She can be reached at


  1. Boyce J. Guideline for hand hygiene in health care settings. Morbidity and Mortality Weekly Report. Available at: Accessed February 15, 2010.
  2. Kohn WG, Collins AS, Cleveland JL, Harte JA, Eklund KJ, and Malvitz DM. Guidelines for infection control in dental health care settings—2003. MMWR Recomm Rep. 2003;52(RR-17):15-18. Available at: Accessed February 15, 2010.
  3. OPRP — General information on hand hygiene. Centers for Disease Control and Prevention. Available at: Accessed February 15, 2010.