Objectives: This study investigated a series of ionomer glasses based on the formula: 4.5SiO(2)-1.5P(2)O(5-)(X)Al(2)O(3)-4.5CaO-0.5CaF(2), where X was varied from 3.0 to 1.5. The possibility of processing ionomer glasses using a heat-pressing method for dental restorations was investigated.
Methods: A simple flow test was designed to measure the amount of flow the glasses underwent as a result of heat-pressing at 1150 degrees C for different times. Heat-pressed samples of the X=3.0, 2.8, 2.4 and 2.0 glass were further heat-treated for 1 and 4 h at 1150, 1200 and 1250 degrees C to promote crystal growth. Scanning electron microscopy was used to investigate the microstructure of the glass-ceramics. X-ray diffraction was used to identify the crystalline phases in the glass-ceramics.
Results: The ionomer glasses exhibited excellent flow ability. Crystallization could not be suppressed during heat-pressing. Very fine scale fluorapatite crystals were present in all of the samples after heat-pressing. Mullite and/or anorthite formed as a second crystal phase. On further heat-treatment of the samples, changes in crystal phases took place.
Significance: Apatite was the main crystalline phase produced in the glass-ceramics; this factor is of clinical significance. In conclusion these glass-ceramics could be suitable for all-ceramic dental restorations.
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http://dx.doi.org/10.1016/s0109-5641(02)00061-1 | DOI Listing |
Eur J Dent
December 2024
Postgraduate Program of Conservative Dentistry Specialist, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia.
Objectives: Calcium carbonate (CaCO), a major inorganic component in bones and teeth, offers potential protection against demineralization. This study investigates the effect of CaCO from shells on the expression of fibroblast growth factor 2 (FGF2), transforming growth factor-β1 (TGF-β1), and collagen type 1 in the rat dental pulp.
Materials And Methods: The first maxillary molars of were perforated and subsequently pulp capped with CaCO extracted from shells.
J Dent Child (Chic)
September 2024
Brazilian Dental Association, all in Natal, Rio Grande do Norte, Brazil.
J Prosthet Dent
December 2024
Professor, Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
Statement Of Problem: Excess cement in implant-supported restorations can lead to peri-implant diseases, and its removal remains a clinical challenge. The optimum method of minimizing excess cement is unclear.
Purpose: The purpose of this in vitro study was to compare 3 cementation techniques and 3 cement types and measure excess cement.
J Funct Biomater
December 2024
Department of Restorative Dentistry, Graduate School of Dental Medicine, Hokkaido University, Sapporo 060-8586, Japan.
This study investigated the effects of resin composites (RCs) containing surface pre-reacted glass ionomer (S-PRG) filler on the dentin microtensile bond strength (μTBS) of HEMA-free and HEMA-containing universal adhesives (UAs). Water sorption (WS) and solubility (SL), degree of conversion (DC), and ion release were measured. The UAs BeautiBond Xtreme (BBX; 0% HEMA), Modified Adhesive-1 (E-BBX1; 5% HEMA), Modified Adhesive-2 (E-BBX2; 10% HEMA), and two 2-step self-etch adhesives (2-SEAs): FL-BOND II (FBII; with S-PRG filler) and silica-containing adhesive (E-FBII) were used.
View Article and Find Full Text PDFDent J (Basel)
December 2024
Department of Biomedical Sciences, School of Dental Medicine, University of Nevada, Las Vegas, NV 89557, USA.
The development of composite resins has led to novel materials aimed at improving restoration longevity. This study evaluates the surface roughness of four tooth-colored restorative materials after thermal aging. Eighty Class V preparations were restored with Admira Fusion, Beautifil II, Equia Forte HT, and Filtek.
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