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Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes
Published on: November 16, 2018
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Pulp Temperature Rise Induced by Light-Emitting Diode Light-Curing Units Using an Ex Vivo Model
Alexandra Vinagre1, João C Ramos2,3, Clara Rebelo4
1Dentistry Area, Faculty of Medicine, University of Coimbra, Avenida Bissaya Barreto, Blocos de Celas, 3000-075 Coimbra, Portugal. avinagre@fmed.uc.pt.
Materials (Basel, Switzerland)
|February 1, 2019
Summary
High-energy light-curing modes significantly increase dental pulp temperature rise. This study found a strong correlation between higher energy density from LED light-curing units and increased pulp temperature.
Area of Science:
- Dentistry
- Biomaterials Science
- Dental Materials
Background:
- Dental light-curing units (LCUs) are essential for polymerizing dental restorative materials.
- Pulp temperature (PT) rise during light curing is a concern due to potential pulpal damage.
- Different light-emitting diode (LED) LCUs and curing modes may induce varying levels of PT rise.
Purpose of the Study:
- To compare the pulp temperature (PT) rise induced by four different LED LCUs in various curing modes.
- To investigate the relationship between energy density delivered by LED LCUs and the resulting PT rise.
Main Methods:
- Eleven extracted premolars were used, with fiber Bragg grating (FBG) sensors inserted into the pulp chamber for real-time temperature measurement.
- Teeth were maintained in a 37.0°C water bath and subjected to random sequences of curing modes from four LED LCUs.
- Curing modes were classified as high-energy (>80 J/cm²) or low-energy (<40 J/cm²), with four 30-second irradiations per mode and temperature reset between exposures.
Main Results:
- All tested LED LCUs induced a statistically significant pulp temperature rise (p < 0.01).
- High-energy curing modes resulted in a PT rise exceeding 5.0°C after four emissions.
- Low-energy modes produced an approximate PT rise of 2.5°C.
- A strong positive correlation (R = 0.715; p = 0.01) was observed between energy density and PT increase.
Conclusions:
- Exposure to LED LCUs causes significant and cumulative pulp temperature rise in intact premolars.
- Curing modes delivering higher energy densities lead to greater pulp temperature variations.
- Radiant exposure is a key factor positively correlated with pulp temperature variation.
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