Effect of Discharge on the Variation in Light Intensity in Three Monowave Light Curing Units in a Dental Clinic Dr. René Puig Bentz: In Vitro Study

This study examined how battery discharge affects light intensity in three monowave LED light-curing units commonly used by students at the Dr. René Puig Bentz Dental Clinic: the Woodpecker® O-Star, the Woodpecker® LED H, and the KP-Dent®. The hypothesis was that a decreasing battery charge would negatively impact the emitted light intensity, which could compromise the quality of resin polymerization and the longevity of dental restorations.
The study employed a quantitative, experimental, in vitro design. The sample consisted of one unit per brand, which was selected based on student surveys. Each device underwent a minimum of 1,250 20-second emissions. Light intensity was measured at regular intervals using a digital radiometer to analyze each unit’s performance from a full battery to near depletion.
The data showed a gradual decline in light intensity across all units as emissions increased. The KP-Dent® unit exhibited the most significant and irregular drop in output, suggesting lower operational stability. In contrast, the Woodpecker® O-Star demonstrated greater consistency and minimal loss of intensity over time, followed by the Woodpecker® LED H.
These findings confirm that battery charge level significantly influences the ability of LED curing units to maintain adequate light intensity. A drop in output may result in incomplete polymerization, which affects mechanical strength, marginal adaptation, and restoration durability.
The study emphasizes the importance of regularly monitoring curing light performance using radiometers. It also suggests that brand, maintenance, and battery status are key factors in clinical effectiveness. These results provide valuable guidance for dental professionals and students when selecting and managing photopolymerization equipment.