Laboratory test
The brush heads in the test rig during the endurance test for 360 minutes. Photo: Anna Sigge
Testfakta Research has, on behalf of Procter & Gamble, conducted a comparative laboratory test of replacement brush heads for Oral-B electric toothbrushes. The purpose of the test is to compare the quality and performance of Oral-B Cross Action and nine compatible brush heads on the Nordic market.
The tests have been carried out by three independent laboratories where the German laboratory SGS Fresenius stands for clinical testing and panel examination, Swedish RISE for tests of endurance and durability and German PZT for tests of technical properties and performance.
The following brush heads have been tested:
All brush heads fit Oral-B toothbrushes in the Pro, Genius and Smart series.
The test includes the following parts:
1. Ability to brush away plaque (clinical test)
The test was performed on a test panel consisting of 40 people. The panel was recruited based on specific criteria regarding plaque level, plaque build-up over 24 hours and general oral health.
The ability to brush away plaque was tested 20 times per brush head. The panelists were randomly assigned to the ten different brush heads and each individual had to visit the laboratory five times to test the different brush heads. Before each visit, panelists were asked not to brush their teeth for 12 hours to allow for sufficient plaque build-up.
Photo documentation of plaque status. Photo: Tobias Meyer
Each visit began with staining of the teeth (plaque staining) followed by examination of the plaque level. After that, the panelist had to brush his/her teeth for a set time and according to careful instructions (the brushing was done under the laboratory’s control). The teeth were then stained again and the plaque level after brushing was examined.
Assessment of plaque was done on the inside and outside of the eight front teeth in the upper and lower jaw and the four inner cheek teeth. The level of plaque before and after brushing was documented with high-resolution photographs that were evaluated by the laboratory’s dentist. Plaque status was assessed individually for each tooth on a five-point scale (Quigley Hines scale). The result per brush head is the average value of approximately 900 assessed teeth and tooth sides before and after brushing.
The dentist assesses the level of plaque based on high-resolution images. Photo: Tobias Meyer
2. Assessment of quality and feel (user panel)
For the user panel test, a total of 200 individuals were recruited and divided into groups of 20 per brush head.
The
laboratory prepares for testing the effectiveness of the brush heads. Photo: Tobias Meyer
Each subject was assigned an electric toothbrush (Oral-B Pro 2) equipped with one of the brush heads. During and after four weeks of home use, the panel members were asked to assess, among other things:
3. The durability of the brush (technical test)
Before the test the properties of the brush heads were documented (weight, length, diameter, brush height and angle of the bristles).
The brush heads in the test rig during the endurance test for 360 minutes. Photo: Anna Sigge
The endurance of the brush head was tested for a total of 360 minutes, corresponding to three months of brushing (2 + 2 minutes per day). Brushing was done against a tooth profile and the angle of the head was changed between straight up, tilted 45° to the left and tilted 45° to the right. The brush head was pressed against the profile with a load of 400 grams on the handle (below the limit of the pressure sensor). A mixture of toothpaste and water was continuously dripped onto the brush head during the test.
After completing the endurance test, the brush heads were thoroughly rinsed, examined under a microscope, and any change in brush hardness was measured.
Assessment of wear on the bristles after endurance test. Photo: Anna Sigge
4. Drop Test (Technical Test)
The electric toothbrush with an attached brush head was dropped in a controlled manner from 70 cm, from different angles onto a concrete floor. After each test, the function of the brush head and any damage was checked.
5. Brush Pressure for Sensor to Respond (Technical Test)
To measure the pressure required for the toothbrush’s pressure sensor to respond, weights of 50 g were applied to the handle until the sensor lit up. During the test, the brush ran with the brush head against a 3D tooth profile.
6. Rotation angle (technical test)
Brush heads for Oral-B toothbrushes rotate at high speed left and right. The angle of rotation, from 0° to the left and right, was measured with the brush head rotating against a tooth profile. The rotation angle was recorded with a high-speed camera.
The laboratory measures the rotation angle with a high-speed camera. Photo: PZT
Measurements were made on new brush heads and heads subjected to endurance tests, both unloaded and with a pressure of 2N. Changes in rotation angle when the head is loaded and after a period of use were assessed in the test.
Interpretation and grading of the laboratories’ test results
All test results have been graded in consultation with the performing laboratories. The grade is set on a scale from 1 to 10, where 10 is the best. Grades below 6.0 have only been given for results that are considered bad or significantly worse than other products in the selection.
In the overall rating, the various test results have been given the following weight:
Brush pressure for the sensor to react has not been rated because the bristles on the different brush heads have different hardness.
