59 research outputs found
Osseointegration of zirconia implants: an SEM observation of the bone-implant interface
Background The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. Methods A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Gottinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Results Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. Conclusion The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level
Group 3 ITI Consensus Report: Patient-reported outcome measures associated with implant dentistry
Objectives: The aim of Working Group 3 was to focus on three topics that were assessed using patient-reported outcome measures (PROMs). These topics included the following: (a) the aesthetics of tooth and implant-supported fixed dental prostheses focusing on partially edentulous patients, (b) a comparison of fixed and removable implant-retained prostheses for edentulous populations, and (c) immediate versus early/conventional loading of immediately placed implants in partially edentate patients. PROMs include ratings of satisfaction and oral health-related quality of life (QHRQoL), as well as other indicators, that is, pain, general health-related quality of life (e.g., SF-36). Materials and methods: The Consensus Conference Group 3 participants discussed the findings of the three systematic review manuscripts. Following comprehensive discussions, participants developed consensus statements and recommendations that were then discussed in larger plenary sessions. Following this, any necessary modifications were made and approved. Results: Patients were very satisfied with the aesthetics of implant-supported fixed dental prostheses and the surrounding mucosa. Implant neck design, restorative material, or use of a provisional restoration did not influence patients’ ratings. Edentulous patients highly rate both removable and fixed implant-supported prostheses. However, they rate their ability to maintain their oral hygiene significantly higher with the removable prosthesis. Both immediate provisionalization and conventional loading receive positive patient-reported outcomes. Conclusions: Patient-reported outcome measures should be gathered in every clinical study in which the outcomes of oral rehabilitation with dental implants are investigated. PROMs, such as patients’ satisfaction and QHRQoL, should supplement other clinical parameters in our clinical definition of success
Expression of genes for bone morphogenetic proteins BMP-2, BMP-4 and BMP-6 in various parts of the human skeleton
BACKGROUND: Differences in duration of bone healing in
various parts of the human skeleton are common experience for
orthopaedic surgeons. The reason for these differences is not obvious
and not clear.METHODS: In this paper we decided to
measure by the use of real-time RT-PCR technique the level of expression
of genes for some isoforms of bone morphogenetic proteins (BMPs), whose
role is proven in bone formation, bone induction and bone turnover.
Seven bone samples recovered from various parts of skeletons from six
cadavers of young healthy men who died in traffic accidents were
collected. Activity of genes for BMP-2, -4 and -6 was measured by the
use of fluorescent SYBR Green I.RESULTS: It was found
that expression of m-RNA for BMP-2 and BMP-4 is higher in trabecular
bone in epiphyses of long bones, cranial flat bones and corpus
mandibulae then in the compact bone of diaphyses of long bones. In all
samples examined the expression of m-RNA for BMP-4 was higher than for
BMP-2.CONCLUSION: It was shown that m-RNA for BMP-6 is
not expressed in the collected samples at all. It is postulated that
differences in the level of activation of genes for BMPs is one of the
important factors which determine the differences in duration of bone
healing of various parts of the human skeleton.Author has checked copyrightDG 16/11/1
A Study of SiR/EPDM Mixtures for Outdoor Insulators
This paper deals with the flashover voltages on samples of silicone rubber/ethylene propylene diene monomer (SiR/EPDM) mixtures under the influence of a uniform electric field. Five different mixtures of SiR/EPDM were investigated. Various SiR/EPDM mixtures (100% EPDM, 10% SiR + 90% EPDM, 30% SiR + 70% EPDM, 50% SiR + 50% EPDM, 70% SiR + 30% EPDM, 90% SiR + 10% EPDM, 100% SiR) were tested for different water droplet arrangements, different water conductivities, different droplet volumes as well as different droplet positioning w.r.t. the electrodes. The 50% SiR + 50% EPDM mixture proved to be the best mixture regarding the flashover voltage
CoCr porous scaffolds manufactured via selective laser melting in orthopedics: Topographical, mechanical, and biological characterization
Implant Materials, Design, and Surface Topographies: Their Influence on Osseointegration of Dental Implants
Duodenal Enteroendocrine I-Cells Contain mRNA Transcripts Encoding Key Endocannabinoid and Fatty Acid Receptors
Effects of implant surface roughness and stiffness of grafted bone on an immediately loaded maxillary implant: a 3D numerical analysis
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