Electric toothbrush
Encyclopedia
Toothbrush
The toothbrush is an oral hygiene instrument used to clean the teeth and gums that consists of a head of tightly clustered bristles mounted on a handle, which facilitates the cleansing of hard-to-reach areas of the mouth. Toothpaste, which often contains fluoride, is commonly used in conjunction...
that uses electric power supplied usually by a battery to move the brush head rapidly, either oscillating side to side, or rotation
Rotation
A rotation is a circular movement of an object around a center of rotation. A three-dimensional object rotates always around an imaginary line called a rotation axis. If the axis is within the body, and passes through its center of mass the body is said to rotate upon itself, or spin. A rotation...
-oscillation (where brush heads rotate in one direction and then the other).
History
The first successful electric toothbrush, the Broxodent, was conceived in Switzerland in 1954 by Dr. Philippe-Guy Woog. Woog's electric toothbrushes were originally manufactured in Switzerland (later in France) for Broxo S.A. The first clinical study showing its superiority over manual brushing was published by Pr. Arthur Jean Held in Geneva in 1956. Electric toothbrushes were initially created for patients with limited motor skills, as well as orthodontic patients (such as those with braces). Claims have been made that electric toothbrushes are more effective than manual ones as they are less dependent upon patients brushing correctly.The Broxo Electric Toothbrush was introduced in the USA by E. R. Squibb
E. R. Squibb
Edward Robinson Squibb was a leading American inventor and manufacturer of pharmaceutics who founded E. R. Squibb and Sons, which eventually became part of the modern pharmaceutical giant Bristol-Myers Squibb....
and Sons Pharmaceuticals at the centennial of the American Dental Association in 1959. After introduction, it was marketed in the USA by Squibb under the names Broxo-Dent or Broxodent. In the 1980s Squibb transferred distribution of the Broxodent line to the Somerset Labs division of Bristol Myers/Squibb.
While the Broxodent may have been the first electric toothbrush and a superior product, the electric toothbrush that caught the public's attention in USA was the General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
Automatic Toothbrush introduced in the early 1960s. Similar to the Broxodent in function, it differed in that it was cordless with rechargeable NiCad batteries, while the Broxodent plugged into a standard wall outlet and run on AC
AC power
Power in an electric circuit is the rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow...
line voltage.
This difference in power source was significant for several reasons. The GE
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
toothbrush, although portable, was rather bulky, about the size of a two-D-cell flashlight
Flashlight
A flashlight is a hand-held electric-powered light source. Usually the light source is a small incandescent lightbulb or light-emitting diode...
handle. NiCad batteries of this period left much to be desired: they suffered from memory and lazy battery effects
Memory effect
Memory effect, also known as battery effect, lazy battery effect or battery memory, is an alleged effect observed in nickel cadmium rechargeable batteries that causes them to hold less charge...
. The GE Automatic Toothbrush came with a charging stand which held the hand piece upright; most units were kept in the charger which is not the best way to get maximum service life from a NiCad battery. Early NiCad batteries did not hold much energy, and it was not uncommon for the GE Automatic toothbrush to run out of power before brushing was complete, particularly if several people used the same battery-holding handle (with separate brushes) without recharging. Finally, early NiCad batteries tended to have a short lifespan. The batteries were sealed inside the GE device, and the whole unit had to be discarded when the batteries failed. The purchase price of each GE Automatic Toothbrush was lower than a Broxodent. The GE Automatic Toothbrush sold well.
The Broxodent hand piece was slim and remarkably compact, even by today's standards. Since it was powered by AC
AC power
Power in an electric circuit is the rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow...
line voltage, it never ran out of power, although it could grow warm after extended use. Early Broxodent models came with a straight power cord, later units with a coiled cord. All Broxodent cords had a small molded strain relief where the cord entered the hand piece, but this was still the likeliest place for a cord to fail. Since the Broxodent hand pieces were sealed, a cord failure was not repairable and the expensive toothbrush had to be discarded. That said, it was not unusual for a Broxodent toothbrush to last for 20 years or longer; failures were rare.
The use of an AC
AC power
Power in an electric circuit is the rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow...
line voltage appliance in a bathroom environment was problematic. By the early 1990s Underwriter Laboratories (UL) and Canadian Standards Association
Canadian Standards Association
The Canadian Standards Association, also known as the CSA, is a not-for-profit Standards organization with the stated aim of developing standards for use in 57 different areas of specialisation...
(CSA) would no longer certify line-voltage appliances for bathroom use. Newer appliances had to use a step-down transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
to operate the actual toothbrush at low voltage (typically 12, 16 or 24 volts). Wiring standards in many countries require that outlets in bath areas must be protected by a RCD/GFCI
Residual-current device
A Residual Current Device is a generic term covering both RCCBs and RCBOs.A Residual-Current Circuit Breaker is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor...
device (e.g., required in USA since the 1970s on bathroom outlets in new construction).
By the 1990s there were problems with safety certification of Broxo's original design. Further, improved battery-operated toothbrushes were providing formidable competition. Broxo S. A. still produces and markets a low-voltage model, but its public visibility in the USA has been limited in the face of large competitors, such as Philips
Philips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
Sonicare
Sonicare
Sonicare is an electric toothbrush manufactured by Philips.-Product and technology:The brush head vibrates at hundreds of times per second, with the latest models at 31,000 strokes per minute...
and Braun
Braun (company)
' , formerly Braun AG, is a German consumer products company based in Kronberg, Germany.From 1984 until 2005, Braun was a wholly owned subsidiary of The Gillette Company, which had purchased a controlling interest in the company in 1967...
Oral-B models. Later Broxo models had no major distributor (such as Squibb) in the USA, and only sell online.
The Broxo low-voltage models used several different methods to attach the actual brushes to the hand piece; however, brushes were often not interchangeable between Broxo models. By the 1990s replacement brushes for line-voltage Broxodent models were no longer sold in the USA, so the original Broxodent Electric Toothbrush was no longer suitable for use there although it had started a trend and sold for over 30 years.
Types of electric toothbrushes
Electric brushes can be classified into two categories according to the type of action that they employ: vibration or rotation-oscillation. When using vibrating toothbrush, a brushing technique similar to that used with a manual toothbrush is recommended, whereas with rotating-oscillating brushes the recommend cleaning technique is to simply move the brush slowly from tooth to tooth.Effectiveness of electric toothbrushes
Independent research finds that although most electric toothbrushes are no more effective than manual brushes—assuming that people using a manual toothbrush will brush effectively—The rotation-oscillation-modelshave been found to be marginally better than manual ones. The research concludes that the way brushing is done is more important than the choice of brush. For certain patients with limited manual dexterity or where difficulty exists in reaching rear teeth, however, dentists strongly feel that electric toothbrushes can be especially beneficial.
The effectiveness of an electric toothbrush depends not only on its type of action and on correct use, but also on the condition of the brush head, which loses its effectiveness over time due to bristle breakdown and wear. Most manufacturers, as well as dental professionals, recommend that heads be changed every three to six months at minimum, or as soon as the brush head has visibly deteriorated.
Power source and charging
Modern electric toothbrushes run on low voltage, 12v or less. A few units use a step-down transformerTransformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
to power the brush, but most use a battery, usually but not always rechargeable and non-replaceable, fitted inside the handle, which is hermetically sealed to prevent water damage. While early NiCad battery toothbrushes used metal tabs to connect with the charging base, modern toothbrushes use contactless inductive charging
Inductive charging
Inductive charging uses an electromagnetic field to transfer energy between two objects. This is usually done with a charging station. Energy is sent through inductive coupling to an electrical device, which then can use that energy to charge batteries....
: the brush unit and charger stand each contain a coil of wire; when placed in proximity, the powered coil from the stand transfers power by induction
Electromagnetic induction
Electromagnetic induction is the production of an electric current across a conductor moving through a magnetic field. It underlies the operation of generators, transformers, induction motors, electric motors, synchronous motors, and solenoids....
to the handle, charging the battery.
Timer
Many modern electric toothbrushes have a timer which buzzes or briefly interrupts power, typically after two minutes, and sometimes every 30 seconds. This is associated with a customary recommendation to brush for two minutes, 30 seconds for each of the four quadrants of the mouth.Display
Some electric toothbrushes have LCDLiquid crystal display
A liquid crystal display is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals . LCs do not emit light directly....
screens which show brushing time and sometimes smiley face icon
Icon
An icon is a religious work of art, most commonly a painting, from Eastern Christianity and in certain Eastern Catholic churches...
s or other images to encourage optimal brushing. These features could encourage people with lower mental capacity and ability, to brush more accurately.