Analysis of Intensity in Different Light Cure Units Used in Dentistry

Jameel Sulaiman

doi:10.33899/rden.2010.8981

Abstract

Aims: The aim of this study was the analysis of intensity in different light cure units used in dentistry. Materials and Methods: Four types of light curing sources units; ULTRA–LITE (LED) Astralis 5 (Halogen), BlueLuxcer.TM (Halogen), Delma (LED), were evaluated for the analysis. Light intensity was recorded at various distances of 0 –16 mm, between the light curing tip and a curing radiometer, and at different times (10, 20, 30 seconds) in low–power and at 5, 10, 20 seconds in high–power. Re-sults: The highest light intensity for the first three types (562 mW/cm2) was obtained by BlueLuxcer.TM – high power when the tip of light curing unit was in contact with a curing radiometer. The light inten-sity for the three types of LCUs decreased significantly (p< 0.05) when the light tip was placed at an angle 700 and distance 0, 2, 4, 6, 8, 10, 12, 14, 16 mm away from the a curing radiometer, and the low-est intensity (38 mW/cm2) was obtained by ULTRA–LITE–LED. But the maximum light intensity for the light cure type Delma–LED, was 772 mW/cm2 and the minimum was 268 mW/cm2 when the light tip was placed perpendicular 900 and distance 0, 2, 4, 6, 8, 10, 12, 14, 16 mm away from the a curing radiometer. Furthermore, no significant differences (p>0.05) were detected between Intensity and vary-ing time at 5, 10, 20, 30 sec. Conclusions: The intensity of the curing light was strongly affected by the angles and distance. The decrease in light intensity was significant (p< 0.05) when the light tip placed at an angle 70° and a way to the aperture of the a curing radiometer, but the magnitude of the intensity it becomes more with the same procedure when the angle was perpendicular 900. The decrease in the light intensity of the light curing units, agree with the inverse square law for the distances 0 to 16 mm. The study found that there was no significant difference (p> 0.05) in light intensity between the light curing tip and a curing radiometer varying with time. This study notice that the intensity of the light cure type LED is less than QTH(Quartz Tungsten Halogen).

Highlights

Several studies presented applied application of the intensity in light cure which are widely used by dentists in his dental clinics
The decrease in light intensity was significant (p< 0.05) when the light tip placed at an angle 70° and a way to the aperture of the a curing radiometer, but the magnitude of the intensity it becomes more with the same procedure when the angle was perpendicular 900
The study found that there was no significant difference (p> 0.05) in light intensity between the light curing tip and a curing radiometer varying with time

Summary

Introduction

Several studies presented applied application of the intensity in light cure which are widely used by dentists in his dental clinics. The effect of light intensity found that when several samples were polymerized in low intensity (390 mw/cm2), they have a degree of conversion less than 10% with high residual monomer, and at 1mm depth. The polyacid–modified composite resin is different in the degree of conversion and an amount of residual monomer at different intensities. As the light intensity increased, the degree of conversion measure is increased, while the residual monomer measure was decreased(4). Polymerization of restorative material using high intensity polymerization devices will sufficiently harden resin, but will lead to greater polymerization shrinkage and stress resulting in micro cracks as a consequence of shrinkage as well as greater increase in temperature that can compromise pulp vitality(5)

Methods

Results

Conclusion