EFFECT OF LIGHT INTENSITY ON THE CURE CHARACTERISTICS OF PHOTO-POLYMERISED DENTAL COMPOSITES

Area of Science:

• Dental Materials Science
• Photopolymerization Technology

Background:

• Light curing units (LCUs) are essential for polymerizing dental composites.
• Variations in LCU light intensity can affect the clinical performance of restorations.

Purpose of the Study:

• To evaluate the light intensity output of LCUs used in dental clinics.
• To determine the correlation between LCU light intensity and the degree of cure (DOC) and surface micro-hardness of dental composites.

Main Methods:

• A cross-sectional laboratory study was conducted.
• LCU light intensity was measured.
• DOC and surface micro-hardness of polymerised composites were assessed across different intensity groups.

Main Results:

• A significant portion of LCUs emitted light at or below 300mWcm⁻².
• Both DOC and surface micro-hardness increased with LCU light intensity up to 1500mWcm⁻².
• Statistical analysis confirmed significant differences in cure characteristics across intensity groups (p<0.002).

Conclusions:

• LCU light intensity is a critical factor influencing dental composite cure characteristics.
• Optimal composite polymerization, indicated by increased DOC and surface micro-hardness, is achieved with LCU intensities up to 1500mWcm⁻².