98%
921
2 minutes
20
The aim of this research was to compare the pulp temperature (PT) rise induced by four light-emitting diode light-curing units (LED LCUs) (Bluephase 20i, Demi Ultra, SPEC 3, and Valo) in different curing modes. Immediately after extraction, the pulp chamber of 11 premolars was accessed from the palatal cervical third of the crown for insertion of fiber Bragg grating (FBG) sensors for temperature measurement and kept in a 37.0° water bath. The teeth were then submitted to a random sequence of curing modes with four irradiations at 30 s intervals. Care was taken to ensure complete pulp temperature reset between curing modes. The curing modes were classified as high-energy (above 80 J/cm²) or low-energy (below 40 J/cm²) according to the total energy density delivered. Statistical analysis was performed with repeated ANOVA measures and Pearson's correlation for the association between energy density and temperature variation. The significance level was set to 0.05. All curing units promoted a statistically significant PT rise (p < 0.01). After four emissions, the PT rise was higher than 5.0 °C for the high-energy curing modes. The low-energy modes induced approximately a 2.5 °C rise. A strong positive correlation was found between energy density and PT increase (R = 0.715; p = 0.01). Exposure of intact premolars to LED LCUs induced significant and cumulative PT rise. Curing modes emitting high energy densities produced higher PT variations. Radiant exposure was positively correlated to PT variation.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6384635 | PMC |
http://dx.doi.org/10.3390/ma12030411 | DOI Listing |
Proc Inst Mech Eng H
September 2025
Faculty of Medicine, Sirindhorn School of Prosthetics and Orthotics, Siriraj Hospital, Mahidol University, Bangkok, 10700 Thailand.
This study provides valuable guidance for simplifying fabrication procedures and enhancing the structural integrity and safety of carbon fiber (CF) laminate transfemoral (TF) prosthetic sockets. While the high specific strength of CF laminate sockets offers advantages over conventional plastics, essential production data-their orientation-dependent strength and optimal cure conditions-are lacking, often requiring complex, costly cure cycles. This study investigated (i) the influence of fiber orientation on TF prosthetic CF socket strength via finite element analysis (FEA) during standing, and (ii) optimal single-step Vacuum-Bag-Only (VBO) cure conditions for prepreg in a low-cost conventional oven.
View Article and Find Full Text PDFClin Oral Investig
September 2025
Department of Mechanical Engineering, Zakir Husain College of Engineering and Technology, Aligarh Muslim University, Aligarh, Uttar Pradesh, India.
Objectives: This in vitro study aims to compare the effect of different light curing modes and curing times on the degree of conversion (DC) and microhardness (MH) of three different bulk fill composites at two different depths.
Materials And Methods: A total of 224 cylindrical specimens (4 mm height, 6 mm diameter) were prepared using four composites: SDR Plus, Ever X Posterior (EXP), Beautifil Bulk Restorative (BBR), and Tetric N Ceram (TNC). Each material group (n = 56) was subdivided into four curing subgroups based on light-curing mode (Low Power or High Power) and exposure time (20-30 s).
Polymers (Basel)
August 2025
School of Aerospace Engineering, Xiamen University, Xiamen 361105, China.
Lightweight composite structures like fiber metal laminates (FMLs) are widely used to manufacture aircraft structures and substitute metallic parts. While the superior mechanical performance of FMLs, including their high specific strength and excellent impact and fatigue resistance, has gained the interest of many researchers in the aerospace manufacturing industry, there are still some challenges that need to be considered. Conventional approaches like lay-up techniques and autoclave molding can achieve the relatively simple FML parts with large radii and profiles required for aircraft fuselages and flat skins.
View Article and Find Full Text PDFJ Clin Exp Dent
July 2025
Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Background: Gallic acid (GA), as a material with potentially beneficial effects in dentistry, was used in this study to investigate whether it affects the shear bond strength of composite to the dentin via self-etch and total-etch strategies of a universal adhesive.
Material And Methods: Sixty intact molars with sectioned flat occlusal surfaces were treated with 1 wt.% and 2 wt.
FEMS Microbiol Rev
January 2025
Department of Microbiology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia.
Host-mediated natural competence for transformation of DNA and mobile genetic element (MGE)-driven conjugation and transduction are key modes of horizontal gene transfer. While these mechanisms are traditionally believed to shape bacterial evolution by enabling the acquisition of new genetic traits, numerous studies have elucidated an antagonistic relationship between natural transformation and MGEs. A new role of natural transformation as a chromosome-curing mechanism has now been proposed.
View Article and Find Full Text PDF