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May 1, 2004
Several months ago, I met a hygienist who is the head of a dental hygiene program. Her school is known far and wide for its high-tech approach to teaching dental hygiene.

by Anne Nugent Guignon, RDH, MPH

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Several months ago, I met a hygienist who is the head of a dental hygiene program. Her school is known far and wide for its high-tech approach to teaching dental hygiene. The school is often referred to as a futuristic playground for dental hygiene students, and the director understandably is very proud of the reputation. Her students graduate, begin practicing, remain in their communities and are still practicing many years later. This program is truly serving the needs of the community.

It is always interesting to hear the point of view of those involved in formal academic settings. Our conversation steered toward the subject of magnification loupes, considered controversial by many in the academic setting. While she acknowledged that loupes were perhaps beneficial, she really felt that her students did not need these expensive devices since they did not need visual enhancement. This was a perplexing situation. Loupes do enhance the clinical image. More importantly, magnification that is properly fitted has a dramatic impact on posture. What was the background to this information gap? However, rather than try to persuade her to see my point of view, I just changed the subject.

It is critical that our profession begin to take responsibility for our own physical well-being. More and more clinicians are either shortening their clinical schedules or dropping out of dental hygiene altogether as a direct result of unresolved pain or disabilities acquired in the workplace. The conversation with the dental hygiene director stayed on my mind. It was reflective of several other disturbing situations that have occurred in the past few years.

After much encouragement, one of my colleagues began wearing magnification loupes during the summer break from her dental hygiene school. When she returned to her part-time teaching position in the fall, she was told that she either had to give up wearing loupes or resign from her position. Her director claimed that loupes gave her an unfair grading advantage over all of the other instructors.

Even though the financial rewards were limited, she loved guiding students. She has a gift for teaching but could not resolve the conflict she felt over her decision to protect herself and provide better visual acuity. She begged the director to research the benefits of magnification. Her requests fell on deaf ears and she finally left the position.

Another colleague of mine is fascinated by technology. She has worn magnification for some time in clinical practice. She appreciated all that this technology can offer to clinicians. She also wanted to introduce her students to a wide variety of devices that can make their clinical days safer and less stressful.

Again, she was the only instructor at the school interested in loupes. It became more difficult for this educator to introduce her students to the benefits of magnification. Her director's justification was amazing: If it's not published, then we can't teach our students about it. An impasse resulted, and she walked away. Fortunately, this talented educator now has another teaching position where her ideas are appreciated.

In direct contrast to these stories, many dental hygiene programs are now encouraging students to wear loupes. It is mandatory in many dental schools now, and dental hygiene programs are more frequently adopting a policy that students wear magnification.

Some schools may feel that students cannot afford loupes, or that they are just not crucial. But the pain, suffering, and financial worries created by developing workplace-related injuries are devastating. Just have a conversation with someone who has been knocked out of the workforce due to neck injury or repetitive stress injury and you'll see a whole other side of the story.

Educating an educator

Imagine my surprise when I ran into the progressive dental hygiene director in the exhibit hall at a large regional dental meeting a couple of weeks ago. She greeted me with a big smile and a hug and said she had been thinking about our previous conversation. I assumed she had dismissed our previous discussion about magnification. Instead, she was still processing the information I had given her. As fate would have it, we were in the aisle across from a loupes manufacturer. We resumed our conversation.

All of a sudden, the director and her friend wanted to see what loupes were all about first-hand. It was thrilling to see the two of them try on different types of magnification loupes, with and without an operator headlight. I could see it in their faces. They understood. They now know why I have been so excited about magnification for so many years.

Before they left the booth, they made an appointment to have a company representative come to their school and talk to the faculty and students. This is really what education is all about — learning from each other and passing the knowledge on. The students at this school are now going to be exposed to one more opportunity to help make their career not only safer but also more exciting.

More than a decade ago, I purchased my first pair of loupes. Initially, it was a very hard decision to make. It was a lot of money for me to spend, and I had only met one hygienist who was wearing loupes. This was uncharted territory and there were very few sources of good information about magnification in dental hygiene publications. It was a scary decision, but my body was falling apart. It became critical to me to figure out a different way to practice. The decision to purchase loupes changed my career forever.

It did take some time getting used to wearing them, but the thought of practicing without them is about as appealing as sticking my hands in someone's mouth without gloves.

Loupes have helped me survive a 33-year dental hygiene career. I can now finish a day free of neck, back, and shoulder pain. My colleagues who wear loupes sing the same song.

Types of magnification

Some clinicians think that reading glasses are an adequate substitute for more expensive magnification systems — an untrue assumption. Reading glasses, which are a single lens, are designed to provide a magnified image at a specific distance, like the view one gets when reading a page in a book. Even though the image is magnified, one is forced to keep the head in a static position to keep the image sharp. In addition, clinicians who wear reading glasses that exceed their personal requirements are forced to lean closer to the oral cavity to keep the image in focus due to the altered working range.

The patient chair is often positioned too high when magnification is not used.
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Several different types of magnification are available for today's dental practitioners. Clip-on loupes are designed with a specific power of magnification, such as 2.0x, in addition to a fixed working range. These loupes offer little more than reading glasses. Loupes made with a series of lenses, housed within the oculars, are known as compound loupes. This type of magnification system creates an image that stays in focus over a range, thus eliminating a static head position. Compound loupes are available in two different styles: flip-up or through-the-lens (TTL).

The working distance of these loupes is not long enough for this hygienist. A properly selected working distance would not allow this clinician to lean forward to treat this patient. Care should be taken to select loupes that are set at the proper working distance to help achieve ideal clinical postures.
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In order to select appropriate magnification, it is necessary to understand six basic concepts: optical resolution, width of field, depth of field, working range, declination angle, and strength.

Each concept determines how comfortable you will be when wearing magnification loupes and how clear the magnified image will be. While the quality of the optics is the biggest factor in determining the price, it is important to consider the number of years that you will wear magnification and purchase the best quality possible.

First, optical resolution refers to the ability to visualize small structures clearly. The higher the resolution of the lens, the clearer the magnified image — just like a computer screen or a high-definition TV screen. Quality loupes will have a clear image across the entire viewing field that does not deteriorate at the edge of the magnified image. Visual acuity improves in direct response to increases in the quality of the optical resolution.

The width of field refers to the size of area being viewed. As we learned in the first day of our microbiology class, the higher the level of magnification, the smaller the field of view. The same is true for magnification loupes. Most hygienists prefer using loupes that allow them to see the entire mouth. Loupes with a smaller width of field are used more extensively in restorative dentistry or during surgical procedures since they provide a more highly magnified image of only a few teeth or a specific area.

Clinicians who wear properly fitted magnification loupes can achieve relaxed, ergonomically friendly postures that include proper head positioning as well as relaxed shoulders and forearms.
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Depth of field is another feature of wearing compound loupes, which are magnification systems that use two or more lenses to produce an enlarged image. Depth of field is measured in inches, with a typical range of four to five inches — the depth of the mouth from lips to distal of the third molars. Loupes with this range allow the wearer to see the entire oral cavity without having to move the head, unlike the fixed position obtained with a reading prescription alone.

This hygienist is leaning her head forward in an unsupported position in order to visualize the patient's oral cavity. Note the rounded shoulders. This poor posture can lead to a variety of workplace-related musculoskeletal disorders.
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The working range and the declination angle are the two factors that most directly impact on the ergonomic benefits derived from wearing loupes. Working range is calculated by measuring the distance from the eye to the actual working field. Unfortunately, many of us have developed poor postural habits through the years and find it uncomfortable to sit up straight. However, measurements should be taken while using perfect posture. To achieve this posture, it is important that the clinician be seated with hips slightly higher than the knees, head held erect, with the shoulders in a relaxed position, upper arms held close to the side, with the forearms parallel to the floor, and the patient positioned at elbow height.

The declination or working angle refers to the angle of the ocular that allows the clinician to see a magnified image while remaining in an ergonomically correct position. If the declination angle is properly set, the clinician will see a clear magnified image while sitting up straight with the head positioned directly over the shoulders. A correct angle helps prevent neck and back muscle strain.

The strength or power of the magnification loupe is frequently reported in terms of diopters. This term does not accurately describe compound loupes that are commonly used by health-care providers, but rather refers to the strength of a single lens found in reading glasses or clip-on magnification systems such as 2.0x, 2.6x or 3.5x. In addition, there is no industry standard regarding the power, so one manufacturer's 2.5x loupes may not equal another company's system that reports the same power of magnification.

Despite this lack of standardization, most dental hygienists find loupes that are marketed as having magnification in the range of 2.5x to 3.2x provide a complete view of the oral cavity. Currently, the most popular magnification strengths are 2.0x, 2.5x and 2.6x. However, since more dental professionals are now wearing loupes, there is an increased demand for higher-powered magnification systems.

Flip-up or through the lens?

The most popular flip-up loupes are designed with a pair of binoculars mounted on either a conventional glasses frame or attached to a pair of lightweight plastic safety glasses. Flip-up loupes can also be mounted on a headband. Once the correct working range is determined, a clinician must set the binoculars to conform to their own visual needs. Periodic readjustment many be necessary.

Flip-up loupes have several unique advantages. Individual eyeglass prescriptions can be modified in the carrier lens by any optician. In other words, if your personal prescription changes, you can have these changes made by your local eye care professional. The loupes can be repositioned so the clinician can look directly at a patient or record through the carrier lens.

Through-the-lens (TTL) magnification provides a fixed custom fit since the loupes are mounted directly into the carrier lens. TTL loupes are fabricated from precise measurements based on a clinician's actual working distance as well as the clinician's declination angle, pupillary distance and convergence point.

Since the ocular in the TTL magnification system is much closer to the eye, the width and depth of field are greater than that of a flip-up configuration with the same level of magnification. In addition, the weight distribution of a TTL system is more comfortable foremost because TTL oculars are mounted directly into the carrier lens while flip-up oculars are mounted on a hinge that attaches to the frames. Through-the-lens configurations also allow a larger volume of light, which is an important factor for those clinicians who require a reading correction.

Selecting a system

Many clinicians have measurements taken at dental meetings. While this works well, it is possible that individual aspects of your treatment room may differ from the height and position of the typodont used in an exhibition hall.

It may be more appropriate to be measured in your own clinical setting. Some manufacturers have representatives that will come to your office to either take initial measurements or to fine-tune the settings in the magnification loupes. Also, it is important to compare the features and quality of different brands of loupes. If you are unsure which will work best, you can always order several different systems. Remember to find out about the manufacturer's trial period and return unwanted products within the company's grace period.

In some cases, several different clinicians may be able to wear the same pair of loupes, but only if each clinician has the same working distance and do not require any vision prescription in the carrier lens.

Many practitioners worry that wearing magnification loupes will cause their vision to deteriorate. In fact, properly fitted loupes lessen eyestrain in addition to improving posture. It is wise to have a current vision examination or any corrective surgery before ordering a pair of loupes. Some manufacturers will include a clinician's specific vision correction in the loupes.

Prescription changes can be handled locally for flip-up models; however, TTL loupes must be returned to the manufacturer for any prescription changes. In addition, it is wise to schedule eye examinations in a timely manner so that any necessary repairs or changes can be made when you are away from your dental hygiene practice for a week or so.

Today's manufacturers offer a much wider variety of frame styles and colors than ever before. Many clinicians consider the style and color important; however, the overall frame durability should be considered as well. Some newer frames are made with much lighter materials that can improve comfort. Keep in mind that larger carrier lenses make it easier to view the patient directly.

Note that frames for plastic safety glasses are only appropriate for clinicians who do not require any vision correction in the carrier lens, and they are not designed to support an operator headlight. Adjustable head straps fastened just behind the head counterbalance the weight of magnification. Various nose pad configurations can also increase clinician comfort.

Company reliability and customer service are also important to consider. Most manufacturers offer some type of payment plan and ample trial periods. If it is difficult to get a pair of bargain loupes repaired or, worse yet, you are left without good customer service, then how important are the dollars that you saved at the front end? Check with your dental hygiene colleagues and listen to their experiences.

Most clinicians make their selection of loupes at a dental convention. However, the true test of magnification comes when working in your own practice setting. Some practitioners adjust to wearing loupes in a couple of days; others require a longer period of time. In order to successfully transition into the world of magnification, it is important to be properly fitted with quality loupes as well as have a desire to make a change in the way you practice. If, after a few days or weeks, the loupes are not performing as you expected, don't hesitate to contact the company. Often, a minor nose pad or temple adjustment can make your new loupes a joy to wear. In rare cases, the system may have to be sent back for readjustment at the factory.

Some hygienists worry that patients or doctors will not accept magnification. If you present the information confidently and clearly, they should understand that you are protecting your body, as well as providing superior service, because you now see more clearly. Since most dentists already wear magnification, they know about the benefits and will view your commitment to your career with a newfound respect. After all, what do you have to lose other than a neck or back ache?

If the initial price of magnification seems high, divide the cost by the number of years you plan to practice. Your body and your patients will thank you for taking a step that will prolong your career and help improve your clinical skills.

The benefits of magnification loupes are enormous and far outweigh the initial cost and possible frustration during the learning curve. Remember how you felt the first time you looked at an image reflected in a mouth mirror? Now it is second nature. Magnification is just as easy. Just give it a try!

The key factors

Perhaps the doctors that you practice with wear loupes. Perhaps you think loupes are for old clinicians or those with failing eyesight. Nothing could be further from the truth. Magnification is a career saver.

If you have never worn magnification loupes, I encourage you to consider the benefits that magnification can provide in your clinical practice. Selecting a good magnification system can seem overwhelming at first. But as soon as you understand the terminology and what to look for, you'll be able to make a purchase that will help you in your practice every day. Factors that should be considered include:

• Type of system — flip-up or through-the-lens
• Strength or power of magnification
• Optical resolution
• Depth and width of field
• Amount of available light
• Weight, frame size, and style
• Manufacturer reliability and customer support
• Company repair and return policies
• Price and payment options

Anne Nugent Guignon, RDH, MPH, practices clinical dental hygiene in Houston, Texas. She writes, speaks, and presents continuing- education courses on ergonomics and advanced ultrasonic instrumentation through her company, ErgoSonics ( She can be reached by phone at (713) 974-4540 or by e-mail at [email protected].