How To Choose Between The Different Types Of Dental Curing Light

dental curing light

If you work in the dental field, you might be familiar with dental curing lights. It is widely used equipment for common procedures. However, with many dental curing light options available in the market today, choosing the best one can be pretty tricky.

If this is your case, then you are on the right page. In this article, you will learn more about the application of dental curing light and how to choose the best one according to your needs.

What Is A Dental Curing Light?

A dental curing light is defined as dental equipment used to cure resin-based composites by polymerization of light. Polymerization is the term used for transforming ‘monomers’ into ‘polymers’. In short, any implants or dental attachments besides the natural teeth are being clean and strengthened by a particular light source.


Monomers are present in dental adhesives. Just like in regular adhesives, the purpose is to attach 2 non-contacting objects and function as a whole. In a dental application, the adhesives aim to stick the attachment towards the gum, root, or foundation on the tooth’s base.

The purpose of curing lights, as mentioned, is to turn monomers into polymers. If you are familiar with the term ‘polymer’, that is because it is the reason why synthetic materials and plastic are so durable and long-lasting. It refers to how the molecules are chained up, and thus, the dental adhesives become stronger knowing that the teeth will undergo a lot of pressure from chewing.

The curing lights used have a wavelength under the visible blue category in the light spectrum. It is just frequencies below from the controversial ultraviolet. The light sources used can be varied depending on the available equipment, and over the years, these have been the 4 basic types: tungsten halogen, LEDs or light-emitting diodes, lasers, and plasma arcs.

Role Of Polymers

Polymers have many dental applications. Here are some of the common dental products:

  • Cement
  • Denture bases
  • Sealants and tooth restoratives
  • Filling materials for root canal
  • Orthodontic space maintainers
  • Cleft palates’ elastics obturators
  • Impressions
  • Provisional restorations
  • Athletic mouthpieces

Some items from the list are temporary attachments, while others are semi-permanent. With the use of dental curing lights, the adhesives used are being reinforced. Here are the 2 ways polymerization can happen:

  • Condensation Polymerization

This encourages reaction from 2 molecules to create a larger 3rd molecule without a small by-product molecule, which is more often water. Every reacting molecule must at least have 2 reactive groups in order to make the resulting product capable of undertaking more condensation reactions.

  • Addition Polymerization

This focuses on joining 2 molecules together to form a larger 3rd molecule. The process involves adding a reactive species that has a monomer to build another larger reactive species that has the capability to repeat the process.

What Are The Different Types Of Dental Curing Light?

As mentioned, there are 4 types of dental curing lights. All of them are capable of achieving the blue wavelength that is intended for polymerization. Among the 4, the two most common are LEDs and halogens.

  • Tungsten Halogen

One of the early dental curing lights is the tungsten halogen curing lights. Developed in the 1980s, they have been the replacement of UV lights by utilizing the blue wavelength. To generate the light, the halogen bulb needs to be energized.

The filament will then reach a temperature of 3,000 Kelvin or roughly 2,700 degrees Celsius. At this point, the visible light will then have a wavelength of 400 to 500 nanometers, which indicate the range for the blue light. With such a very high temperature, a powerful ventilating fan, which is already a part of the machine, is very much necessary.

So far, the technology is proven to be very useful until the emergence of a much more efficient generation of light such as the other 3 types. With the generation of great heat in halogen bulbs to achieve light, the ventilation fan is being used to its full potential just to cool down the operation, and thus, unnecessary noise from its mechanical action is also being produced in the process.

  • Plasma Arcs

In the 1990s, there have been improvements in dental light-curing devices. A fluorescent bulb that contains plasma generates a light source of high intensity. According to the claims, within just 3 seconds, the resin composite material will be ‘cured.’

The bulb is a high-pressure vessel made from aluminum oxide. It contains xenon gas that is highly energized under a pressure of 150 psi. While the arc is made between 2 energized electrodes, the reflectors direct a focused beam. It is, without a doubt, effective, but the procedure costs a lot.

  • Lasers

If you are familiar with argon lasers, they are usually used for medical practices. More commonly, you might have encountered that procedure in an eye clinic. Due to its effectiveness in generating such a focused light source, it is seen as effective for dental curing light.

The argon laser utilizes the noble gas ‘argon’ as the medium for the light to pass through. The light will become more concentrated and, thus, termed as ‘laser.’ However, using lasers can be too much on the budget for dental applications.

  • LEDs Or Light-Emitting Diodes

Although lasers and plasma arcs are more efficient than tungsten halogen lights, they are very impractical, financially speaking. And here comes the newcomer, the light-emitting diode or LED. This semiconductor component is capable of emitting a wide spectrum of light without wasting energy in generating heat or having an expensive operating cost.

Since there is not much energy wasted as heat, small ventilation fans can be enough. Even with all the great things about LEDs, they too have limitations. They cannot generate more power compared to the other 3, but with numbers, that can be compensated.

They rely on chemical reactions for luminescence and might be prone to be busted if excessive energy is flown through the bulbs. Throughout the years, LEDs are still developing yet have now become the top light source both commercially and industrially. There is no wonder that even the development of new dental curing lights is gearing more towards the LED technology.

How To Choose The Right Type Of Dental Curing Light?

For curing the resin-based composites, it is important to use the right type of curing light. Upon installation of the resin-based composites, there are already particular instructions on the specification of lights to be used. Sometimes, the dentist recommends a specific product, but let’s discover what factors determine the choice for a dental curing light.

  • Intensity

The more intense the light, the better is the chance of success in polymerizing. However, resin-based composites can have different requirements, and therefore, it will be better if the light source can be varied.

The unit ‘mW/cm2’ or ‘milliwatt per square centimeter’ is used when measuring the amount of light from a curing light. You can look for your resin-based composites’ intensity requirements and choose a light source based on that.

  • Wavelength

One aspect or quantity of light that matters is the wavelength. The shorter they are, the higher their frequency is, and that relates to the ‘penetrating’ capability of the light. For an analogy, ultraviolet light and X-rays have shorter wavelengths than blue light, ergo, they have higher frequencies, and that explains why light at those spectrums passes through organic matter easily.

Some resin-based composites have a specific wavelength requirement in order for the light source to penetrate the material. For practicality, choose a product with a range of wavelength compatible with most resin-based products.  

  • Polymerization Programs

The polymerization program refers to how the dental curing light is carrying out the polymerization. Apparently, the light will eventually reach its intended level of operation but getting it is crucial.

Why? Certain materials react to stress, and there is stress involved as light is being emitted. Here are the usual programs for polymerization.

  • Ramp Up = progressively increasing the intensity
    • Staggered = alternating between the minimum and maximum intensity
    • Constant maximum power level
  • Lamp Design

Technically, the 3 factors are enough. However, you need to consider the lamp design for the sake of the user’s comfort. Remember that the light source is used for curing the composite installed on the tooth or gums, and that involves hygiene which might affect the overall health.

A great design considers the ergonomics, weight, and tip angle. Make sure that the light can reach the back molar’s occlusal surface while the device can be easily cleaned off. Additionally, the tip rotation helps since an off-angle light will not be effective in curing than the one shining directly.

  • Electrical Attachment

If you have older devices, you probably deal with the inconvenience of maneuvering the light curing device when the wire is on the way. The wireless card can help you solve that problem, but you might constantly be worrying about battery life. In this aspect, as you choose the right type, make sure you factor in how long you might be operating the light curing device.


Generally, the LED type of dental curing light is the best choice. It is far more energy-efficient and, at the same time, safe. However, it will still boil down how much intensity and frequency (or wavelength) are needed by the resin-based composite installed in your mouth or your dental attachment.