Materials and Methods: Twenty-five enamel slabs were divided into three treatment groups: light-activated bleaching, laser-activated bleaching, and control. The baseline data were recorded for enamel microhardness (Vickers microhardness [VMH]) and surface roughness (Roughness average, Ra). The specimens were cured for 10 min upon hydrogen peroxide application for the light-activated bleaching group and activated with a laser source, 8 cycles, 10 s per cycle for the laser-activated group. The changes in VMH and Ra at days 1, 7, and 28 were evaluated. Kruskal-Wallis, Friedman, Wilcoxon, and Mann-Whitney tests were used to analyze both VMH and Ra between the treatment groups at different time intervals.
Results: There were a significant reduction in VMH values and significant differences between days 1, 7, and 28 against the baseline in the light-activated bleaching group (P = 0.001). The Ra values revealed significant differences in both light- (P = 0.001) and laser-activated (P = 0.033) groups.
Conclusion: Light activation of a bleaching agent caused a reduction in enamel microhardness and an increase in surface roughness when compared to laser activation.
MATERIALS AND METHODS: Five male New Zealand White rabbits weighed between 1.5 and 4.0 kg were anesthetized and their livers were exposed. 18 liver biopsies were performed under control group (without tract ablation, n = 9) and study group (with tract ablation, n = 9) settings. The needle insertion depth (~3 cm) and rate of retraction (~3 mm/s) were fixed in all the experiments. For tract ablation, three different needle temperatures (100, 120 and 150 °C) were compared. The blood loss at each biopsy site was measured by weighing the gauze pads before and after blood absorption. The rabbits were euthanized immediately and the liver specimens were stained with hematoxylin-eosin (H&E) for further histopathological examination (HPE).
RESULTS: The average blood loss in the study group was reduced significantly (p
METHODS: 35 maxillary incisors were endodontically prepared. A dimensionally stable silicone material was injected into the root canal space and scanned with CBCT. The root canal volume was measured using Romexis 3.0.1 R software. Replicas were carefully removed from the teeth and scanned using an extraoral laser scanner. These images were exported to the Rhinoceros software for volume measurement. The volume of each replica was also assessed using the gravimetric method. To determine the accuracy, the volume obtained from both devices was compared with the gravimetric method. Statistical analysis was done using a paired t-test. The reliability was assessed using the intraclass correlation coefficient.
RESULTS: There was no statistically significant difference between the mean volume of CBCT 27.04 ± 7.25 mm³ and the mean volume of the gravimetric method 27.87 ± 7.17 mm³ (P< 0.05). A statistically significant difference was seen with the laser scanner at 25.31 ± 6.89 mm³ and the gravimetric method at 27.87 ± 7.17 mm³ (P< 0.05). CBCT showed a good degree of agreement (ICC 0.899), while the laser scanner showed a moderate degree of agreement (ICC 0.644) with the gravimetric method. CBCT proved accurate and reliable in measuring minor volumes like the root canal space, ideally in the range of 20-25 mm³. The laser scanner presented acceptable reliability.
CLINICAL SIGNIFICANCE: The laboratory data showed satisfactory outcomes, providing an evidence-based approach and potentially motivating clinicians to integrate cone-beam computed tomography for volume analysis into clinical practice. The accuracy and reliability of laser scanners for small-volume analysis have not previously been evaluated. Consequently, the findings from this study warrant further clinical investigations.
METHODS: Patients were divided into two groups according to the type of laser employed [Holmium:YAG (HL) or Thulium fiber laser (TFL)]. Residual fragments (RF) were defined as > 2 mm. Multivariable logistic regression analysis was performed to evaluate factors associated with RF and RF needing further intervention.
RESULTS: 4208 patients from 20 centers were included. In whole series, age, recurrent stones, stone size, lower pole stones (LPS), and multiple stones were predictors of RF at multivariable analysis and LPS and stone size with RF requiring further treatment. HU and TFL were associated with lesser RF and RF requiring an additional treatment. In HU
OBJECTIVE: The main objective of this paper is to develop a robust algorithm to extract respiration rate using the contactless displacement sensor.
METHODS: In this study, chest movements were used as an indicative of inspiration and expiration to measure respiratory rate using the contactless displacement sensor. The contactless optical signals were recorded from 32 healthy subjects in four different controlled breathing conditions: rest, coughing, talking and hand movement to obtain the motion artifacts that the patients may have in the emergency department. The Empirical mode decomposition (EMD) algorithm was used to derive continuous RR signal from the contactless optical signal.
RESULTS: The analysis showed that there is a good correlation (0.9702) with RMSE of 0.33 breaths per minutes between the contact respiration rate and contactless respiration rate using empirical mode decomposition method.
CONCLUSION: It can be concluded that the empirical mode decomposition method can extract the respiration rate of the contactless optical signal from chest movement.