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Accuracy of LED and halogen radiometers using different light sources
Howard W Roberts1, Kraig S Vandewalle, David W Berzins
1Graduate Dental Biomaterials, Marquette University, Milwaukee, WI, USA. hwroberts@nidbr.med.navy.mil
Summary
Handheld LED and halogen radiometers show similar accuracy for measuring curing light irradiance, though light guide diameter impacts readings. These devices are largely interchangeable for clinical use.
Area of Science:
- Dental materials science
- Photopolymerization technology
- Metrology in dentistry
Background:
- Accurate measurement of curing light irradiance is crucial for effective dental restorations.
- Commercially available handheld radiometers are widely used but their accuracy can vary.
- Understanding the performance of different radiometer types and light guide sizes is essential.
Purpose of the Study:
- To evaluate the accuracy of handheld light-emitting diode (LED) and halogen-based radiometers.
- To compare these radiometers when used with LED and quartz-tungsten-halogen (QTH) curing lights.
- To assess the influence of various light guide diameters on irradiance measurements.
Main Methods:
- Irradiance measurements were taken using LED and halogen curing lights with multiple handheld LED and halogen radiometers.
- A laboratory-grade power meter served as the control for comparison.
- Measurements were performed using light guides with diameters of 4, 7, 8, 10, and 12.5 mm.
Main Results:
- Both handheld radiometer types showed significant differences compared to the control meter.
- Readings between LED and halogen radiometers were slightly different but correlated.
- Larger light guides tended to overestimate irradiance, while smaller guides tended to underestimate it.
Conclusions:
- Handheld LED and halogen radiometers can be used interchangeably for measuring curing light irradiance.
- The observed differences between radiometer types are likely not clinically significant.
- Light guide diameter can affect measurement accuracy, impacting the reliability of irradiance readings.
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