A dental curing light is a piece of dental equipment that is used for polymerization or Curing of light cure resin based Dental Composites. It can be used on several dental materials that are curable by light. The light used falls under the visible blue light spectrum. This light is delivered over a range of wavelengths and varies for each type of device. There are four basic types of dental curing lights halogen and light-emitting diode (LED), plasma arc curing (PAC), and laser. The two Most Common dental curing lights are the halogen and LED.
We Have Many Dental Curing lights To Chose From all at a Very Low Price. The Higher the Curing Power, the quicker the Cure of Composite. The measure of power is measured in W/cm2. There is also a wavelength, which is anywhere from 410 - 530 nano meters, which is the effectiveness of the curing light to cure all different types of composite and bonding agents. The wider the nano meters, the more bonding agents and composites a light can cure. All Dental Curing lights now have a wide enough range to cure all Bonding agents and Dental Composites.
LED Dental Curing Light
Curing lights are an essential part of any operatory, and are a great example of how technology can be leveraged to improve the overall experience for both the clinician and the patient. They are primarily used on different dental materials that are curable by light. Curing lights that use light-emitting diodes (LED) are at the forefront of technology and innovation.
LED curing lights, in particular, use visible blue light spectrum and provide a wide range of wavelengths for the quick and accurate polymerization of light cure resin-based composites.
They’re generally easy to handle and ideal for hard-to-reach places, providing optimal curing treatment in the least amount of time.
Technology in dentistry has evolved over the last few years. Sleeker designs and smaller frames have improved the accessibility of curing lights in the oral cavity and improved the user experience. Additionally, these devices have become more lightweight, portable and easier to handle which makes it much more enjoyable for you when it fits comfortably in your hand. They also use less power than previous-generation devices.
Using less power for every curing treatment has a couple of advantages. It cuts down on the amount of time for each treatment to just a few seconds and reduces the risk that the device will overheat. This is an important benefit of LED curing lights, especially if you’re curing a third molar or a different hard-to-reach area and you’re worried about overheating. Generally, these curing lights will cut down on potential patient discomfort and make your life easier.
Another advancement of LED curing lights is that many have multiple levels of powers. Some operate in 3 different curing modes: standard-power, high-power, and plasma-emulation, which gives you more control depending on the case. That control is important for any dental clinician when they’re looking for the highest quality device for your operatory.
The ability to easily and effectively cure polymer-based restorative materials using light energy has revolutionized the field of dentistry over time.
For a light-cured resin-based restoration to function and last as intended, it must receive the required amount of light energy at the proper wavelength (i.e., the wavelength of the photoinitiator) to facilitate optimal polymerization.
To deliver the required amount of light energy, it is necessary to understand how clinical variables such as curing tip distance and angle of incidence with respect to the restoration surface influence the curing process, as well as exposure time and curing tip diameter.
Proper infection control procedures when using curing lights support both patient safety and equipment maintenance.
It is important to consider that curing lights can cause an intrapulpal temperature rise. Proper eye protection helps prevent blue-light-induced retinal injury.
Photoactivated dental materials, including certain sealants, resin-based cements and composite restorative materials, are an integral part of general dental practice. Dental light curing units (LCUs) are handheld light-emitting devices used to cure such photoactivated, polymer-based restorative materials.
Dental professionals spend considerable time performing tasks that involve using PBRMs, and the convenience of being able to rapidly light cure these dental materials has transformed dentistry over time. In the contemporary marketplace, there are a wide variety of dental LCUs, and the technology has developed continually since photocuring was first used in dentistry
Dental Curing Light Technology
Photopolymerization is a light-activated reaction that uses visible light energy to activate a photoinitiator system, which absorbs light photons and produces reactive species (free radicals) that initiate the polymerization process. In dentistry, resin-based composite materials are commonly comprised of a polymer resin matrix and inorganic filler particles. As long as the wavelength of the light matches the absorption range of the photoinitiator with sufficient energy, a variety of light sources may be used for photopolymerization in dentistry. One of the most commonly used photoinitiators in dental resins is camphorquinone (CQ).4 The peak absorption range for CQ is from 455 to 481 nm, with peak absorption at approximately 469 nm.
The first Dental light-cured resins used in dentistry date to the early 1970s and were cured using ultraviolet (UV) LCUs. The photoinitiators used with these materials were based primarily on benzoin methyl ether or similar types of photoinitiators activated by UV. Examples of concerns about early UV-curing LCUs included resin color instability, limited depth of cure, and UV-promoted tissue damage, such as acute and longer-term eye damage. However, shortly after the introduction of UV-curing, dental materials were reformulated to include visible light wavelength photoinitiators, such as CQ. As a result, curing units designed to emit UV light were replaced with Light Curing Units that emit light in the visible spectrum, including quartz-tungsten-halogen (QTH) lights.
In contrast to UV LCUs, QTH curing units emit blue light as part of their spectral output, require shorter curing times and are associated with lower risk of cataracts. However, the blue wavelengths emitted by QTH LCUs are not without their own risks, such as the risk of direct retinal damage. In the mid-1980s researchers advised clinicians to wear blue blockers for ocular protection, and in 1986, the ADA issued a recommendation to wear appropriate protective filtering eyeglasses when using this type of Dental Light Curing Unit.
Dental Curing Light Use
Training. The type of Dental Curing Light Unit and the technique employed by the person using it can have a significant effect on the quality of the restoration, and there is potential for considerable variability in radiant exposure delivered by different operators.
A preclinical light-curing simulator called MARC (Managing Accurate Resin Curing) was developed to help clinicians learn proper curing techniques. MARC uses simulated restorations and provides values for irradiance received by the restorations during curing, along with radiant exposures. MARC also provides the spectral distribution for the curing light. A study using the MARC simulator found that the actual amount of light energy deposited on a restoration was often much less than that estimated by the clinician.
Common terms: Irradiance (Radiant Incidence), Radiant Exitance, Power, and Radiant Exposure. The word “intensity” is often used in discussing curing lights, but the terms “irradiance” (radiant incidence) and “radiant exitance” are more precise. Irradiance (radiant incidence) is a measure of the radiant power striking a specific area and emitting from the curing unit tip; radiant exitance is a measure of the power radiated outward from a source of a specific area (e.g., from the curing unit tip).
Irradiance is dependent on the power striking a specific surface area and, thus, can vary with distance from the curing unit tip. By contrast, the radiant exitance of a curing unit is a constant value, since the area of the curing unit tip and the power radiated from this tip are both for the most part constant (“for the most part” is used here because, just like a home-use light bulb, the power can slowly change over time as the bulb ages and then fails; with LCUs, power can also change if the tip is damaged or contaminated). Irradiance and radiant exitance are often reported in mW/cm2 by Dental Curing light manufacturers. Radiant exitance is also recommended to be included in the manufacturer’s instructions for use, according to the American National Standard Institute/American Dental Association (ANSI/ADA) and International Organization for Standardization (ISO) standards for dental LCUs.
Another term commonly used when characterizing LCUs is power. Similar to the constant rate at which water flows out the nozzle of a hose, the power radiated by a LCU can be reported as a rate (energy emitted per unit time), which can be expressed in joules per second (J/s). The power emitted by lights is typically reported in watts (W), like home-use light bulbs that have a power rating of 40 W, 60 W, 75 W, etc. Watts can also be used to express the power output of an LCU. However, because dental light curing is done over a period of time, such as 10 or 20 seconds, the power output of a curing unit can be thought of as a rate, with 1000 mW being equal to 1 W, which is equal to 1 J/s. When thinking about how much light energy is deposited on a restorative material, power can be considered as a rate that is multiplied by curing time to yield energy, as described in the next section on radiant exposure.
Another important term for understanding the process of curing polymer-based restorative materials is radiant exposure, which is used to describe the total amount of light energy deposited on the material during curing. Radiant exposure can be determined by multiplying the irradiance by the curing time. That is, the radiant power striking the area of the resin being cured can be multiplied by curing time to yield radiant exposure. As stated above, thinking about power in terms of rate makes it easier to consider the total amount of light energy deposited on the polymer-based restorative material during curing. For example, when irradiance is expressed in joules per second per area (J/s/cm2) instead of W/cm2, it can more easily be seen that multiplying irradiance by curing time (in seconds) yields radiant exposure, or energy deposited on the restoration during curing, in J/cm2. Therefore, if the irradiance value is 1000 mW/cm2 and the curing time takes 20 seconds, then 20 joules of energy have been delivered to the area of resin that the curing light is striking. This is because the 1000 mW/cm2 can be expressed as 1 W/cm2 or 1 J/s/cm2, and then multiplying by the 20-second curing time yields 20 J/cm2, or 20 J of light energy deposited on the area of resin the curing light is striking.
There are a number of considerations to be taken into account when purchasing an Dental Curing Light Unit.
Battery life
The current state-of-the-art battery type is lithium-ion. Nickel cadmium (NiCad) batteries do not provide long-lasting charges and are thus avoided by many dentists. Clinicians can think about the longest exposure duration they perform and how many times that exposure is delivered to see if a given battery will last for a given procedure or set of procedures. In battery-operated Light Cring Units, the amount of curing time that each full charge offers can vary from about 26 minutes to 164 minutes.
Beam divergence and footprint of light
If a light is shined on a piece of paper, the uniformity of light can be examined. Some areas may appear brighter than others. Beam spread can also be qualitatively measured by slowly moving the light tip away from the piece of paper and noticing how quickly the size of the circle increases.
Effective light range
The term “blue LED” is not necessarily consistent between lights and does not mean that it will cure all resins. Lights emitting between 455-481 nm are most effective as they span the peak absorption range for camphorquinone.
Energy needed for polymerization
Consider the amount of energy needed to polymerize the bottom-most layer of the restoration when selecting from lights with different outputs.
Heat dispersion
LED chips can be driven past their capacity and potentially overheat, and light output of the LCU can be greatly reduced if excess heat is not removed. Metal heat sinks are designed to absorb excess heat generated at the chip. If the LCU feels very light without the battery inside, then there may not be a heat sink in it. Some LED lights have built-in thermostats designed to automatically shut down after reaching a threshold temperature.
Infection control method
The gold standard for infection control is removable light tips that can be autoclaved. Some disinfectants can negatively impact the LCU by harming the light-transmitting ability of glass-fibered light guides or by degrading plastic cases, lenses, light guides, and electronics.
Intraoral ergonomics
Clinicians can check whether the LCU light tip can reach difficult locations in the mouth, especially in children who may not sit still or older patients who may have limited range of motion in the jaw.
Intrapulpal temperature
Clinicians can test how much heat is produced by shining a light on the underside of the wrist. If shining the light begins to cause discomfort before the necessary amount of cure time has elapsed, the clinician may want to reconsider using that LCU for that amount of time.
Multiple wavelengths
Poly-wave LED lights emit light at multiple wavelengths, which is useful for curing composites with more than one photoinitiator. It is also worth noting that the different beams in poly-wave LCUs do not mix well, so on a given surface, it is quite possible that one area is receiving light at one wavelength while another area is receiving light at a different wavelength. The clinician may thus need to move the curing light across the surface to help ensure that the composite is receiving light at all of the necessary wavelengths.
Turbo tip and focal effect
Turbo tips focus the power over a smaller area, resulting in an increased irradiance. This smaller area means, however, that repeated, overlapping exposures will be needed to cure across the surface of the restoration. Turbo tips also have a focal effect, where the focal point is the distance away from the site where measured irradiance is greatest. If the tip is held farther away than this, it will deliver less irradiance than a standard tip.
Unit integrity
Squeeze the handle of an LED light before buying. If there are cracks or openings between the sections, fluids or disinfectants may be able to enter through those openings. Activation buttons that are blister covered will be less likely to allow these fluids to interfere and cause damage to electronic components.
Use of a handheld radiometer
Bring a handheld radiometer to trade shows to compare the light intensities of different LCUs. Radiometers are not always accurate to match the manufacturer’s stated output, but they are consistent enough to compare one light to another. Other Lights like Diadent D-LUX+ dual-wavelength Cordless LED Curing Light.
