A process that started with creating a standard test for viewing the cleaning performance of ultrasonic cleaners on dentures came to a result as the Sonic 1, an ultrasonic denture cleaner for the company Dental Robotics. Cleaning performance, use(r scenario), and aesthetics were essential pillars in the process. Oral hygiene is essential for people’s overall health. Poor oral care is a significant concern among the elderly, especially in nursing homes as older people struggle to take good care of their teeth because they sometimes do not know how, and on the other hand, they are not capable anymore. Proper oral care is necessary for people with their teeth, but also for people with a denture, what a large number of people have in nursing homes. With dentures, infections can quickly occur. Food can be easily trapped between the teeth and will rot as the person does not feel this himself. The current way of cleaning a denture is time consuming, dirty, and it is often forgotten. The starting point of the project will be ultrasonic cleaning, as this technique shows promising features. Testing In order to perform all the test in the same way, a standard test is created. Because dentures with ‘real’ dirt, dentures which are used by people, are not all the time available, fake dirt needed to be found to imitate real dirt. With the created standard test, multiple tests were performed to determine per parameter if changing it improves the cleaning performance a lot. Cleaning agent: a cleaning agent (soap or a denture cleanser) makes sure the denture is better cleaned however, the improvement is not very large. Cleaning a denture alone of upper and lower together: there is no significant difference because at some places it cleaned better and at some places less. Time: a longer cleaning period than five minutes does fit. It is certainly a recommendation to clean longer than five minutes, probably even longer than thirty minutes.
Temperature: The advice concerning cleaning temperature is that a higher temperature than twenty-five degrees is definitely preferable. A temperature between fifty and seventy degrees would be optimal, taking into account that the water also heats up during the process. Orientation: The conclusion from the orientation tests is that the side facing the piezo is cleaned the best and therefore it might be convenient to use multiple piezo’s in one cleaner in order to not have to turn the denture around. Distance: The advice for the parameter of distance to piezo is that it should be as short as possible, as the vibrations are there the strongest. The water is damping the vibrations when the object is placed further away from the source. Final design When the Sonic 1 is turned on, an heating element at the bottom of the tank, heats the water up to fifty degrees Celsius. The sensor keeps on measuring during the cleaning process; if the temperature rises above seventy degrees, the piezo’s are switched off for a certain period of time in order to let the temperature degrease until fifty degrees again. Then the cleaning process is started again. The cleaning process is taking up half an hour, with the piezo’s switching every 1.5 minute. During the whole cleaning process the denture is soaking in the water, which makes the filth looser and easier to remove. When the first piezo removes certain filth, the filth layer below has time to soak and can be easier removed when the first piezo is back on. After the cleaning cycle, the basket is moved upwards out of the water in order for the dentures to dry. At the same time, the motor is also pressing the lid open so air can come in.
Unique selling point of the product As the denture cleaner is specific designed for the nurses of a nursing homes, it has some unique selling points over all other ultrasonic cleaners and other ways of cleaning dentures: The denture cleaner is easy in use as it is possible to pick the cleaner up from the charger by the handle, walk to the sink and fill the product. With disposing the water it is similar. Other ultrasonic cleaners are lacking a spout and/or have the cord attached which makes is harder to walk towards a sink. The denture cleaner is cleaning all sides of the denture as there are more piezo’s in the product.