Consequences of Dental Occlusion Enhancement by Means of Metal Crowns on the Animal Model

Abstract

The purpose of this study was to determine whether there is a correlation between induced occlusal trauma and the occurrence of oxidative stress in the hippocampus. Twenty Wistar rats were randomized into three experimental groups and one control group. Animals in the experimental group were cemented modified crowns on molars to induce occlusal trauma in 7, 14 and 30 days. To evaluate the oxidative stress, blood was drawn from the hippocampus at 7, 14 and 30 day intervals. Oxidative stress was evaluated using the following specific tests: determination of plasma malondialdehyde and serum glutathione values. The results of the study demonstrate that malocclusion experienced by raising the vertical dimension in rats resulted in significant reductions in antioxidants and increase level of free radicals.

The Effect of Glazing on Full Contour Zirconia - A Systematic Review

“…Due to its exceptional biocompatibility, low cytotoxicity, chemical stability, high mechanical strength, superior fatigue resistance, high fracture resistance, and hardness, zirconia is frequently utilized in prosthetic dentistry. Zirconia is utilized to create individual dental crowns, brief fixed partial dentures, and implants due to its qualities and the further advancement of digital technology equipment (59). The development of new zirconia ceramics for dental restorations is ongoing with the aim of retaining mechanical integrity while enhancing translucency.…”

The Impact of Increase in the Vertical Dimension of Occlusion on Nociception in Rats - A Preliminary Report

“…As previously described, literature data offer the confirmation that change in VDO (by means of an increased dimension) may result in characteristic stress-response behavioral features (25). Since the alterations in VDO represent the specific trauma that causes chronic stress (7), it has been observed that this prosthetic intervention leads to increased sensitivity to pain, manifested by the decline in pain threshold.…”

“…Unfortunately, due to lack of data for the interconnection between VDO raise and the pain tolerance in animal experimental models, we are not able to compare our results with the literature. Therefore, we can only try to make an indirect explanation based on the fact that VDO increase has been reported to result in chronic stress (7), while the chronic exposure to stressors resulted in the nociceptive changes, producing hyperalgesia (16). Hormozi and co-workers reported that after three weeks of electric foot-shock stress, hyperalgesia was observed due to decreased expression of spinal cord µopioid receptors.…”

“…When adaptive abilities are exceeded, this change can lead to the side effects on the structures of the orofacial system that affects patient functionality, comfort and aesthetics (6). Occlusal interferences in the form of increasing VDO are common in clinical practice, and associated with the development of chronic stress (7) which results in pain and overload of the masticatory muscles and temporomandibular joints (TMJ), as well as central nervous system (CNS) (8).…”

Recent Modifications of Zirconia in Dentistry

“…Magnesia is the dopant of this type, usually using (8-10 mol%) of MgO to provide a biphasic composition of precipitates of tetragonal intragranular zirconia within the cubic matrix of stabilized zirconia through the introduction of magnesium cations within the tetragonal or cubic lattice of zirconia [9,21]. Although (Mg-PSZ) exhibits transformation toughening with good chemical and thermal resistance properties, this material had precluded from several biomedical applications, it is considered an unstable material; due to its inferior properties resulting from the large grain size, which in turn increases the residual porosity and makes it susceptible to wear.…”