Design of a Self Cleaning Dental Mirror

An exercise in empathic design

Robin Oglesbee-Venghaus - Pratt Institute - Spring 2013

Empathic DesignEmpathic design is a multi-phase, human centered process which is used to understand and clarify the needs of a user or demographic. Thereby allowing the designer to design something truly useful.

UNDERSTANDING

DEFINING

IDEATING

PROTOTYPING

VALIDATING

REFINING

Empathic design consists of six key phases. Starting with understanding, the designer works through each phase to refining, repeating any phase or sequence as necessary.

Enabling Dentists to be Faster and More AccurateAfter closely observing two dentists, Dr. Linda Ngo and Dr. Megan Uhlorn, I decided that the most pressing need that I could address was vision. For a dentist to be able to work fast and accurately they need to be able to see easily and comfortably inside a patient’s mouth.

I have designed a simple solution to address Dr. Ngo and Dr. Uhlorn’s need to see clearly inside a patient’s mouth. I kept their current low-tech set up of a mirror attached to handle, but I incorporated three distinct innovations. The first innovation is a new shape for the head of the mirror which conforms closely to the contours of the patients mouth. The second innovation is a slightly larger ergonomic handle. The third innovation is the addition of a small “windshield wiper” controlled with an easy to use slider on the handle. The wiper uses a serpentine motion to clear the mirror of debris and moisture. This feature enables the dentist to clean the mirror without having to reposition it, saving time and increasing accuracy.

Designed for Ease of Use

User Profile

SituationDr. Uhlorn and Dr. Ngo work at 170th Dental in the Bronx, NY. 170th Dental is a small dental clinic that is part of a larger chain of dental offices located in the greater New York area. Dr. Uhlorn and Dr. Ngo are the only dentists who work at 170th Dental. They each have an assistant, and there is a receptionist who takes care of the front desk. There are no dental hygienists and thus Dr. Uhlorn and Dr. Ngo are responsible for the full range of dental care, from routine cleaning to extractions. 90% of their patients are from either the Dominican Republic or Puerto Rico and can be considered low-income. The clinic is setup with a fixed rate for each procedure and Dr. Uhlorn and Dr. Ngo receive 35% of the billed cost of each procedure they perform. If they are not doing a procedure, they don’t get paid. The clinic does not provide medical benefits or any paid leave. For Dr. Uhlorn and Dr. Ngo it is almost as if they are self employed.

Dr. Megan Uhlorn & Dr. Linda Ngo

Understanding

“I can’t imagine doing anything else. I love that people leave feeling better than when they came in.”

Job DescriptionDr. Uhlorn and Dr. Ngo diagnose and treat problems with a patient’s teeth, gums, and related parts of the mouth. They provide advice and instruction on taking care of teeth and gums and on diet choices that affect oral health.Some of the tasks Dr. Uhlorn and Dr. Ngo regularly perform are:• Remove decay from teeth and fill cavities• Repair cracked or fractured teeth and remove teeth• Straighten teeth to correct bite issues• Place sealants or whitening agents on teeth• Give anesthetics to keep patients from feeling pain during procedures• Write prescriptions for antibiotics or other medications• Examine x rays of teeth, gums, the jaw, and nearby areas for problems• Make models and measurements for dental appliances, such as dentures, to fit patients• Teach patients about diet, flossing, use of fluoride, and other aspects of dental care

Dr. Uhlorn injects a patient with anesthetic.

AEIOUThe AEIOU exercise provides a framework for analyzing observation by separating it into different categories.

Understanding

ActivitiesAdjusting patient’s chair.Removing temporary fillings.Injecting anesthetic.Grinding.Drilling.Shaping teeth.Installing metal studs.Taking impressions.Applying adhesives.Suctioning.Spraying water and air.Wiping mirror.Putting on gloves.Changing burrs.Scraping plaque.

EnvironmentsSmall room with only enough room for patient in chair, dentist and assistant. The door usually remains open. No windows in room. Main light source is overhead fluorescent, supplemented by one task light. The dentist sits in a rolling office chair and the assistant sits in a special chair with a curved armrest that they can lean on. The room has white walls linoleum tile flooring.

InteractionsDr. Uhlorn’s main interactions are with her assistant, her patients and the other dentists. The interactions with her patients are probably the most important but also the hardest because many of the patients do not speak English as their first language. When the patients do not speak English, Dr. Uhlorn’s assistant acts as a translator. Dr. Uhlorn also interacts intimately with her tools. She usually has her mirror in her left hand and some other instrument in her right.

ObjectsAir/water sprayerExplorer/pickScalerSyringeMirrorDrillsBurrsBite blockSuction tubeForcepsAdhesive gunsGlasses with loupesCotton gauzeInstrument trayX-ray machine

UsersThe primary users are Dr. Uhlorn and Dr. Ngo, their assistants and their patients.

Interpretation170th Dental is a dynamic office serving mostly lower income patients whose first language is usually Spanish. The office is moderately equipped with only two dentists on staff. The dentists perform most general dentistry tasks from routine cleaning to root canals and the installation of prosthetics. Although they use many specialized tools, the one they use the most is a simple dental mirror. Dr. Uhlorn and Dr. Ngo seemed to be holding their mirrors in their hands at all times. Sometimes they were using the mirror to hold the patient’s cheek back or to move the patient’s tongue. Most often they were using it to see what they were working on. No matter what they were using it for, the simple dental mirror seemed to be the most essential tool.

What? | How? | Why?What? | How? | Why? is a tool that can help a designer drive to deeper levels of observation. This simple scaffolding allows one to move from concrete observations of the happenings of a particular situation to the more abstract potential emotions and motives that are at play in the situation one is observing.

Understanding

What?Dr. Ngo carefully works on her patient’s teeth while her assistant looks on.

How?Dr. Ngo is hunched forward, peering into her patient’s mouth. She looks like she is straining to see what she is doing. Her assistant has removed the suction tool from the patient’s mouth and is waiting to put it back.

Why?Dr. Ngo is working on a tooth that is in the back of the patient’s mouth. Plus she is using two different tools at once, so there is no room for the suction tool and she has to strain to see what she is doing.

Needs & Criteria

Defining

Dr. Ngo & Dr. Uhlorn

AdministrationProceduralInteraction

Safety Ease of execution

Ergonomics Vision PrecisionSpeed

To better define Dr. Uhlorn and Dr. Ngo’s needs I charted major facets of their jobs.

NeedAfter much observation and analysis I have identified the need to easily, comfortable and clearly see inside the patient’s mouth as Dr. Ngo and Dr. Uhlorn’s most pressing need.

Criteria·Inexpensive·One handed operation·Must be able to be used to retract tongue and cheek·Comfortable for patient·Able to be sterilized in autoclave·Allow dentist to see all areas of mouth easily·Must not interfere with other instruments·Dentist’s view should not be obstructed by spraying water, flying debris or warm, wet breath

Current practiceDr. Ngo and Dr. Uhlorn currently use a low-tech solution comprised of a small (1” dia.) round mirror, attached at approximately 50 degrees to a six inch long rod like handle, to see inside a patient’s mouth. This method is actually quite successful and fulfills most of the criteria I have established. The one place that it falls short is the last point. Dr. Ngo and Dr. Uhlorn are forced to frequently stop what they are doing so that they can wipe debris and water off the surface of their mirrors. Stopping to wipe their mirrors adds to the time it takes to complete a procedure. At the same time, the hassle and time cost of wiping their mirrors encourages the dentists to try to proceed with impaired vision, thus compromising their ability to perform to the fullest of their abilities.

State of the ArtI looked into how others have tried to meet the need to see inside a patient’s mouth,- where they have succeeded and where they have fallen short.

Understanding

Standard mirror meets most criteria but must be removed from patient’s mouth to be cleaned.

Disposable mirror also meets most criteria but must also be removed fro patient’s mouth to be cleaned. In addition it is not environmentally friendly.

Double sided mirror is similar to standard mirror but has added benefit of second reflective surface - not really that useful because of angle of head.

Mirror with suction at head helps keep mirror surface clean but requires a suction hose attached to handle which is unacceptable to most dentist.

Battery powered mirror spins mirror surface at high speed causing debris and moisture to be flung off. Self cleaning without the need for a hose but extremely expensive and somewhat clunky.

Mirror surface is cleaned by a jet of high pressure water or air. May work but also requires hose attached to handle.

Brainstorming and SketchesAs part of the ideation process I brainstormed and sketched possible solutions to Dr. Uhlorn and Dr. Ngo’s need.

Ideating

After brainstorming and sketching possible solutions that might fulfill my criteria, I decided to pursue the idea of incorporating a wiper mechanism into a simple mirror assembly.

Initial Prototypes

I started out with some simple prototypes to explore different shapes for the mirror surface.

Prototyping

I then made some simple prototypes to test button placement.

Dr. Uhlorn tested my prototypes and expressed a preference for the larger button located so that she could operate it with her thumb.

Functional Prototype

Prototyping

The flexible wiper mid wipe.

The rack and pinion gear system

On the real mirror the gear mechanism will be contained within the handle and body.

Refined Prototype

Prototyping

Incorporating Dr. Uhlorn and Dr. Ngo’s feedback and building off my earlier models, I have designed a prototype that is both simple to use and more comfortable to hold.

Validating

ValidatingI brought my refined prototype to the dental office and asked Dr. Ngo to use it for a whole procedure.

Dr.Ngo uses the refined prototype to perform the installation of a crown.

Checking the fit of a crown.

“This is so great, so comfortable. I really like the shape of the mirror, it is easier to see with. The blue and white is very clean looking. I like it.”

Evaluation

Refining

Further DevelopmentsI have not been able to find the right material to make the wiper blade out of so that it is flexible enough to spring back and forth while at the same time creating the right amount of downward pressure to completely clean the mirror surface. I feel that it is totally possible to make my design work if only I could find the right material.

Meets Need and Fulfills CriteriaAlthough I feel that I was successful in designing an innovative solution to meet the stated need that also fulfills all of my criteria, there are parts of my design that still need work.

Refinements and EnhancementsWhile she liked the way the new handle shape of my refined prototype felt in her hands, Dr. Ngo expressed interest in a smaller version to free up more space in the patient’s mouth for other instruments. I think it would be valuable to make a couple more versions in different sizes to find the perfect one.