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LED vs halogen light-curing of adhesive-precoated brackets
Davide Mirabella1, Raffaele Spena, Giovanni Scognamiglio
1University of Ferrara, Ferrara, Italy; Private practice, Catania, Sicily.
The Angle Orthodontist
|February 27, 2008
Summary
Blue light-emitting diode (LED) curing units show similar orthodontic bracket failure rates to conventional halogen lamps. This study found LED curing offers faster bonding times without compromising bracket retention, with fewer failures in the maxillary arch.
Area of Science:
- Orthodontics
- Dental Materials Science
- Biomaterials Engineering
Background:
- Adhesive-precoated (APC) orthodontic brackets are widely used.
- Curing light technology, including halogen and blue light-emitting diode (LED) units, impacts bracket bonding efficacy.
- Evaluating the failure rates associated with different curing methods is crucial for clinical practice.
Purpose of the Study:
- To compare the failure rates of APC orthodontic brackets bonded with blue light-emitting diode (LED) curing units versus conventional halogen lamps.
- To determine if LED curing units result in a higher incidence of bracket failures compared to halogen lamps.
- To assess the clinical performance of APC brackets under different light-curing protocols.
Main Methods:
- A randomized clinical trial involving 65 patients and 1152 stainless steel APC brackets.
- Each patient's mouth was divided into four quadrants for direct comparison of halogen and LED curing units.
- Bracket failure data were collected over a mean period of 8.9 months and analyzed using various statistical tests, including chi-square and Kaplan-Meier survival estimates.
Main Results:
- No statistically significant difference in bond failure rates was observed between APC brackets cured with LED light and those cured with halogen light.
- A significantly lower percentage of bracket failures occurred in the maxillary arch (1.67%) compared to the mandibular arch (4.35%) irrespective of the curing light used.
- The study demonstrated comparable bracket retention between the two curing light technologies.
Conclusions:
- The hypothesis that LED curing units produce more failures than halogen lamps could not be rejected.
- Blue light-emitting diode (LED) curing units offer comparable APC bracket failure rates to conventional halogen lamps.
- LED curing units provide a significant advantage with a substantially shorter curing time (10 seconds) compared to halogen lamps.
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