When you go to dental office to get a filling done, you may have seen the assistant using a blue light on the filling. You might have asked what it's for and found out that the material is hardened by light. This is in fact a curing light.
What is a curing light?
It is an equipment used in the dental office. The light has a visible spectrum of blue. Curing means polymerization or hardening of monomers in the resin based filling materials. (This is the composite filling or tooth-coloured filling).
The dental curing light produces visible light and not UV light.
Since the prolonged exposure to this blue light can burn the retina, the dental personals use a shield to protect their eyes.
When was it introduced?
Light curing dental materials were introduced in the 1960s. The curing light was introduced in the 1970s. The first curing light used UV light to cure the material. During the 1980s chemists discovered visible light that can be used to cure resin materials.
Types of curing light in Dental offices
There are mainly two types of curing lights used by dentists: halogen curing light and LED curing light.
Halogen curing light has a tungsten filament, which is inside a bulb filled with halogen gas. When the light turns on, current passes through tungsten filament and heats it up to produce UV light and visible light. There is a filter in the equipment to absorb all the UV light, and lights other than the blue spectrum. This unit produces a lot of heat, so a cooling fan is also added in the equipment. Some practices still use this.
LED is widely used because it is lighter than the halogen. They are more cost effective and longer lasting compared to halogen curing lights. Being battery powered makes them portable as well. The heat generated is very less so no cooling fan is necessary.
With the discovery of curing light, new light activated materials were introduced to dentistry. The new resin materials can be placed directly on the tooth without mixing different materials. It saves time in delivering treatment and the material is cured enough so the filling will be perfect.
What do you think of curing light now? Have you ever thought about the use of chemistry in dentistry? If you have any questions about curing light, please reply below!