PMID: 7988755Jul 1, 1993Paper

The strengthening mechanism of a magnesia core ceramic

Dental Materials : Official Publication of the Academy of Dental Materials
W J O'BrienT Y Tien


A high-expansion core material containing magnesia and forsterite may be used to make all-ceramic dental crowns with porcelain-fused-to-metal body porcelains. The purpose of this study was to investigate the strengthening mechanism for the magnesia core material. Six batches of the magnesia core material were made by reacting magnesia with a silica glass with holding times ranging from 17 to 120 min. The flexural strength was measured using three-point loading according to the ISO specification for dental ceramics. The forsterite content was measured using quantitative x-ray diffraction. A statistically significant correlation was found between the forsterite content and flexural strength. The proposed mechanism for strengthening is the precipitation of fine forsterite crystals in the glass matrix surrounding unreacted magnesia. Longer reaction times produced more dissolution of magnesia and subsequent precipitation of forsterite. This method results in a new strengthening mechanism for dental ceramics which have previously relied on the incorporation of alumina, leucite or ceramic whiskers.


Jul 1, 1990·Dental Materials : Official Publication of the Academy of Dental Materials·R R SeghiA Caputo
Sep 1, 1967·The Journal of the American Dental Association·J W McLean
Oct 1, 1983·Journal of Dental Research·M R EdwardsG J Williams

❮ Previous
Next ❯


Apr 1, 1995·Journal of Dentistry·D BrownD C Watts
Jan 1, 1996·Critical Reviews in Oral Biology and Medicine : an Official Publication of the American Association of Oral Biologists·I L Deany

❮ Previous
Next ❯

Related Concepts

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Hereditary Sensory Autonomic Neuropathy

Hereditary Sensory Autonomic Neuropathies are a group of inherited neurodegenerative disorders characterized clinically by loss of sensation and autonomic dysfunction. Here is the latest research on these neuropathies.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Landau-Kleffner Syndrome

Landau Kleffner syndrome (LKS), also called infantile acquired aphasia, acquired epileptic aphasia, or aphasia with convulsive disorder, is a rare childhood neurological syndrome characterized by the sudden or gradual development of aphasia (the inability to understand or express language) and an abnormal electroencephalogram. Discover the latest research on LKS here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.


Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Regulation of Vocal-Motor Plasticity

Dopaminergic projections to the basal ganglia and nucleus accumbens shape the learning and plasticity of motivated behaviors across species including the regulation of vocal-motor plasticity and performance in songbirds. Discover the latest research on the regulation of vocal-motor plasticity here.