Purpose: To study luminescence, reflectance, and color stability of dental composites and ceramics.
Materials And Methods: IPS e.max, IPS Classic, Gradia, and Sinfony materials were tested, both unpolished (as-cast) and polished specimens. Coffee, tea, red wine, and distilled water (control) were used as staining drinks. Disk-shaped specimens were soaked in the staining drinks for up to 5 days. Color was measured by a colorimeter. Fluorescence was recorded using a spectrofluorometer, in the front-face geometry. Time-resolved fluorescence spectra were recorded using a laser nanosecond spectrofluorometer.
Results: The exposure of the examined dental materials to staining drinks caused changes in color of the composites and ceramics, with the polished specimens exhibiting significantly lower color changes as compared to unpolished specimens. Composites exhibited lower color stability as compared to ceramic materials. Water also caused perceptible color changes in most materials. The materials tested demonstrated significantly different initial luminescence intensities. Upon exposure to staining drinks, luminescence became weaker by up to 40%, dependent on the drink and the material. Time-resolved luminescence spectra exhibited some red shift of the emission band at longer times, with the lifetimes in the range of tens of nanoseconds.
Conclusions: Unpolished specimens with a more developed surface have lower color stability. Specimens stored in water develop some changes in their visual appearance. The presently proposed methods are effective in evaluating the luminescence of dental materials. Luminescence needs to be tested in addition to color, as the two characteristics are uncorrelated. It is important to further improve the color and luminescence stability of dental materials.
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http://dx.doi.org/10.1111/j.1532-849X.2011.00808.x | DOI Listing |
BMC Pulm Med
January 2025
Universal Scientific Education and Research Network (USERN), Tehran, Iran.
Objective: Lung cancer (LC), the primary cause for cancer-related death globally is a diverse illness with various characteristics. Saliva is a readily available biofluid and a rich source of miRNA. It can be collected non-invasively as well as transported and stored easily.
View Article and Find Full Text PDFBMC Oral Health
January 2025
State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Implant Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
Purpose: This study aimed to evaluate the osteogenic performance of allograft particulate bone and cortical bone blocks combined with xenograft under bovine pericardium membranes, for treating different degrees of labial bone defects in the aesthetic zone.
Materials And Methods: Twenty-four patients with bone defects were divided into two groups based on defect severity (Terheyden 1/4 and 2/4 groups). The Terheyden 1/4 group received granular bone grafts alone, while the Terheyden 2/4 group received cortical bone blocks combined with granular bone grafts.
J Craniomaxillofac Surg
January 2025
Department of Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Introduction: The purpose of this European multicenter study was to describe and assess the characteristics, diagnosis, management, and recurrence of oral malignant melanoma at different European oral and maxillofacial surgery centers.
Materials And Methods: This study was based on a systematic computer-assisted database that allowed the recording of data for all primary oral mucosal melanomas treated in the involved surgical units across Europe between January 1, 2003 and December 31, 2022. The following data were recorded for each patient: gender, age, site, TNM staging, metastases, symptoms, imaging features, histopathological features, treatment, complications, recurrence, follow up, and survival.
Biomaterials
December 2024
Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China; Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Beijing, China. Electronic address:
In situ bone regeneration and vertical bone augmentation have been huge problems in clinical practice, always imposing a significant economic burden and causing patient suffering. Herein, MgZnYNd magnesium alloy rod implantation in mouse femur resulted in substantial subperiosteal new bone formation, with osteoimmunomodulation playing a pivotal role. Abundant macrophages were attracted to the subperiosteal new bone region and proved to be the most important regulation cells for bone regeneration.
View Article and Find Full Text PDFWest Afr J Med
September 2024
.Department of Preventive Dentistry, Lagos State University, College of Medicine, Faculty of Dentistry, Ikeja, Lagos, PMB 21266, Nigeria.
Background: Indirect pulp capping is the main treatment modality for reversible pulpitis.
Objective: To evaluate the efficacy of Biodentine® and Calcium hydroxide in the formation of dentin bridge.
Materials And Methods: A double blinded, randomized clinical control trial involving 50 consenting subjects, aged 16 to 55 years with deep carious vital teeth.
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