Comparison of load bearing capacity of ceramic crowns with zirconia or polyetherketoneketone frameworks.

Aim: The aim of the present study was to compare the load bearing capacity of monolithic or bilayered single crowns with zirconia or polyetherketoneketone frameworks designed and fabricated using CAD/CAM systems.

Materials And Methods: Cr-Co-based metal dies (n = 60) were duplicated from an extracted and prepared premolar and then restored with different CAD/CAM materials. The specimens were divided into five groups (n = 12) according to the type of materials: group S: monolithic zirconia-reinforced lithium disilicate; group ZI: bilayered zirconia framework with lithium disilicate; group ZE: bilayered zirconia framework with resin-infiltrated hybrid ceramic; group PI: bilayered polyetherketoneketone (PEKK) framework with lithium disilicate; group PE: bilayered PEKK framework with resin-infiltrated hybrid ceramic.

Effects of sintering protocol and dipping time on the optical properties of monolithic zirconia.

Statement Of Problem: The use of monolithic zirconia for restorations has become popular. However, the effects of the coloring process and sintering procedure on the optical properties of monolithic zirconia remain unclear.

Purpose: The purpose of this in vitro study was to evaluate the effects of the different sintering protocols and dipping times on the CIELab color parameters, color difference (ΔE), translucency parameter (TP), opalescence parameter (OP), and contrast ratio (CR) of monolithic zirconia.

Evaluation of various denture cleansers on color stability and surface topography of polyetherketoneketone, polyamide, and polymethylmethacrylate.

The aim of this study was to evaluate the effect of sodium perborate effervescent tablets and citric acid solution on the color stability and surface topography of a new generation of high-performance polymer polyetherketoneketone (PEKK), thermoinjection-molded polyamide, and polymethylmethacrylate (PMMA). Fifty disc-shaped specimens were fabricated (10 mm × 2 mm) from PEKK (P group), polyamide (D group), and PMMA (M group). These groups were divided into five subgroups (n = 10) according to the storage media.

Effect of cleansers on denture base resins' structural properties.

Introduction:: We assessed the effect of different available denture cleansers on the roughness and hardness of polyetherketoneketone, thermoinjection-molded polyamide, and polymethylmethacrylate.

Materials And Methods:: A total of 150 disc-shaped specimens were fabricated (10 mm × 2 mm) from these three denture base resins, and divided into five subgroups ( n = 10) according to immersion procedures. One of these groups subjected to distilled water served as control, whereas other groups were subjected to daily cleansing with four denture cleansers (Corega, Protefix, Curaprox, and Perlodent) for 8 h a day for 140 days.

Adult case of acrodysostosis with severe neurologic involvement.

Objective: Acrodysostosis is a rare syndrome characterized by peripheral dysostosis, nasal hypoplasia and frequently mental retardation. Only one adult case of acrodysostosis has been reported to have neurologic symptoms. We report one further adult case of acrodysostosis with severe neurologic findings including myelopathy and spastic paraparesis due to diffuse spinal stenosis and recurrent deep vein thrombosis possibly caused by neurologic deficits.

Spinal cord injury associated with thoracic osteoporotic fracture.

This report details a case of sudden neurologic deficit attributable to acute thoracic fractures associated with senile osteoporosis. A 73-yr-old female patient with a history of occasional back pain during the past 4 mos had sudden thoracic vertebral fracture with spinal cord injury. The patient, who had a benign past medical history, had not been evaluated for osteoporosis.