Objectives: The aim of this finite elemental stress analysis study was to evaluate the effect of cavity shape and hybrid layer on the stress distribution of the mandibular premolar tooth under occlusal loading.
Methods: The mandibular premolar tooth was selected as the model based on the anatomical measurements suggested by Wheeler. Four different mathematical models were evaluated: 1) a saucer-shaped non-carious cervical lesion restored with a composite without a hybrid layer, 2) a saucer-shaped non-carious cervical lesion restored with a composite with a hybrid layer, 3) a wedge-shaped non-carious cervical lesion restored with a composite without a hybrid layer, and 4) a wedge-shaped non-carious cervical lesion restored with a composite with a hybrid layer. A 200 N force was applied from the buccal tubercule and central fossa of the premolar tooth. The findings were drawn by the SAPLOT program.
Results: In models 2 and 4, the output showed that a hybrid layer acts as a stress absorber. Additionally, when the cavity shape was changed, the stress distribution was very different.
Conclusions: Cavity shape and hybrid layer play an important role in stress distribution in cervical restorations.
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J Mol Model
January 2025
College of Mechanical Engineering, Changzhou University, Changzhou, Jiangsu Province, China.
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January 2025
Fujian Provincial Key Laboratory of Fire Retardant Materials, College of Materials, Xiamen University, Xiamen, 361000, People's Republic of China.
In recent decades, annual urban fire incidents, including those involving ancient wooden buildings burned, transportation, and solar panels, have increased, leading to significant loss of human life and property. Addressing this issue without altering the surface morphology or interfering with optical behavior of flammable materials poses a substantial challenge. Herein, we present a transparent, low thickness, ceramifiable nanosystem coating composed of a highly adhesive base (poly(SSS-co-HEMA)), nanoscale layered double hydroxide sheets as ceramic precursors, and supramolecular melamine di-borate as an accelerator.
View Article and Find Full Text PDFMod Pathol
January 2025
Department of Pathology and Laboratory Medicine, University of Miami.
Human papillomavirus (HPV) underpins approximately 90% of squamous cell carcinomas (SCC) of the anus and perianal region. These tumors usually arise in association with precursor lesions such anal intraepithelial neoplasia/ high-grade squamous intraepithelial lesion (AIN 3/ HSIL), whereas a small subset of HPV-negative cancers may harbor mutations in TP53. Recently, vulvar lesions termed differentiated exophytic vulvar intraepithelial lesion/vulvar acanthosis with altered differentiated (DEVIL/VAAD) have been recognized as HPV-independent, TP53 wild-type precursors for vulvar carcinoma; however, analogous anal lesions have not been described.
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January 2025
School of Chemistry, Dalian University of Technology, Dalian 116024 PR China. Electronic address:
The development of electrode materials for aqueous ammonium-ion supercapacitors (NH-SCs) has garnered significant attention in recent years. Poor intrinsic conductivity, sluggish electron transfer and ion diffusion kinetics, as well as structural degradation of vanadium oxides during the electrochemical process, pose significant challenges for their efficient ammonium-ion storage. In this work, to address the above issues, the core-shell VO·nHO@poly(3,4-ethylenedioxithiophene) composite (denoted as VOH@PEDOT) is designed and prepared by a simple agitation method to boost the ammonium-ion storage of VO·nHO (VOH).
View Article and Find Full Text PDFComput Methods Programs Biomed
January 2025
Regional Institute of Ophthalmology, Indira Gandhi Institute of Medical Sciences, Patna, 800025, Bihar, India.
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