The occurrence of postoperative tooth sensitivity after application of pulse-lighting curing units in different time

Restorative procedures may lead to tooth postoperative sensitivity. The objective of this study was to observe postoperative tooth sensitivity in dental patients after application of light curing units. The clinical trial included 90 subjects with occlusal Class I carious lesions. Subjects were given a resin composite restoration and assigned into 3 groups based on the chosen light-curing unit: (i) a pulse lighting curing unit of 1,000 mW/cm2 in 10 sec, (ii) a pulse lighting curing unit of 1,000 mW/cm2 in 20 sec, and (iii) a single light exposure from a continuous lighting curing unit of 900 mW/cm2 in 20 sec, as a comparison. After light curing, weasked the subjects using a questionaire containing 6 questions of tooth sensitivity at time points, i.e., at the time ofthe light exposure; right after light exposure; 15, 30, 45 and 60 minutes after light exposures. The assessment was based on the four-level sensitivity of none (score=1), slight (score=2), moderate (score=3) and severe (score=4). Reply of each patient on the presence or absence of the sensitivity was recorded as a postoperative tooth sensitivity score providing the total score is 6 (minimum) to 24 (maximum). Results showed that 87.8% of subjects reported post operative tooth sensitivity score of 6; 8.9% and 3.3% of the subjects showed light sensitivity (scores 7 and 8, respectively), however, the sensitivity faded away within 15 minutes. The application of the experimental curing units observed insignificant difference intooth sensitivity when using the pulse lighting at 1,000 mW/cm² in 10 or 20 sec, and also when those were compared to the commercially available continuous lighting at 900 mW/cm²in 20 sec.