Chemical Fixation Importance of Histologic Samples for Staining of Proliferated Bone During Implant Osseointegration

This study aimed to obtain as much and as accurate information as possible about the process of osseointegration of titanium implants, through histological processing. For this purpose, the combination of a mercury chloride fixator (Stieve mixture) and a complex staining method (Goldner’s trichrome) was used, which can highlight the microscopic structures in several colors and shades. The Stieve mixture proved to have distinguished qualities both in the preservation of basophilic and acidophilic structures and especially in the chemical preparation of the substrate for the binding of each structural component with a specific acidophilic dye. On the substrate thus prepared, the acidophilic dyes used in the Goldner’s trichrome staining highlighted the structural components in different colors and shades, offering the possibility of high precision assessment of the newly proliferated bone, in different stages of proliferation, consolidation and reshaping. Complex information was obtained, which allows the appreciation of osseointegration for endosseous implants and the amount of proliferated bone at the bone-implant interface, the stage of proliferation, consolidation and reshaping of the mature bone, the degree of fixation to deep bone structures. The possibility of complex assessment of the osseointegration process for endosseous implants at a given time is of great practical importance for correct assessment of the waiting time required for safe installation of prosthesis. The combination of Stieve fixator mixture with Goldner’s trichrome staining method has proven to be very effective in histology, highlighting on excellent level the existing structural components of each stage, in which the osseointegration process goes through. A very important role in this combination was achieved by mercury chloride mixture, which prepared the substrate for specific reaction with dyes. Regarding the results obtained, we recommend this combination for histological investigations aimed on bone proliferation and repair.

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Osseointegration interface of calcified bone and endosseous implants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130110 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1096-1097

Author(s):

K.E. Krizan ◽

J.E. Laffoon ◽

M.J. Buckley

Keyword(s):

Structure And Function ◽

Titanium Implants ◽

En Bloc ◽

Endosseous Implants ◽

Ultrastructural Studies ◽

The Past ◽

Cacodylate Buffer ◽

One Year ◽

And Function

With increase use of tissue-integrated prostheses in recent years it is a goal to understand what is happening at the interface between haversion bone and bulk metal. This study uses electron microscopy (EM) techniques to establish parameters for osseointegration (structure and function between bone and nonload-carrying implants) in an animal model. In the past the interface has been evaluated extensively with light microscopy methods. Today researchers are using the EM for ultrastructural studies of the bone tissue and implant responses to an in vivo environment. Under general anesthesia nine adult mongrel dogs received three Brånemark (Nobelpharma) 3.75 × 7 mm titanium implants surgical placed in their left zygomatic arch. After a one year healing period the animals were injected with a routine bone marker (oxytetracycline), euthanized and perfused via aortic cannulation with 3% glutaraldehyde in 0.1M cacodylate buffer pH 7.2. Implants were retrieved en bloc, harvest radiographs made (Fig. 1), and routinely embedded in plastic. Tissue and implants were cut into 300 micron thick wafers, longitudinally to the implant with an Isomet saw and diamond wafering blade [Beuhler] until the center of the implant was reached.

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Anagen Effluvium after Therapeutic Scalp Surgery: Unreported Phenomenon

Skin Appendage Disorders ◽

10.1159/000513087 ◽

2021 ◽

Vol 7 (4) ◽

pp. 311-314

Author(s):

Leticia Arsie Contin ◽

Leopoldo Duailibe Nogueira Santos ◽

Ivan José Netto Pereira ◽

Vanessa Barreto Rocha

Keyword(s):

Hair Loss ◽

Spontaneous Recovery ◽

Case Reports ◽

Practical Importance ◽

Transient Ischemia ◽

Melanocytic Nevi ◽

Scarring Alopecia ◽

Anagen Hair ◽

Time Required

Introduction: Many procedures are performed on the scalp, such as excision of pilar and sebaceous cysts, melanocytic nevi, and reduction surgery for scarring alopecia, among others. In hair transplants, telogen effluvium is often reported 3 months after surgery; however, hair loss usually happens much earlier, around second week after the procedure, not compatible with the time required for hair to enter telogen and exogenous phases in normal conditions. Case Reports: We report 3 cases of anagen hair loss 4 weeks after surgeries, with perilesional trichoscopy suggesting anagen effluvium, with typical signs such as black dots and exclamation hairs. Discussion: There are only a few reports about hair loss around operated areas. The cause of this postoperative anagen effluvium is probably a transient ischemia. Conclusion: The practical importance of this phenomenon is to properly orient patients because most of the hair will be lost, since 85% of them are anagens, and also will have spontaneous recovery in the next 3 months.

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Trade-offs between driving nodes and time-to-control in complex networks

Scientific Reports ◽

10.1038/srep39978 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 13

Author(s):

Sérgio Pequito ◽

Victor M. Preciado ◽

Albert-László Barabási ◽

George J. Pappas

Keyword(s):

Complex Networks ◽

Time Window ◽

Empirical Studies ◽

Practical Importance ◽

Network Models ◽

Small Time ◽

Synthetic Network ◽

Trade Offs ◽

Minimum Number ◽

Time Required

Abstract Recent advances in control theory provide us with efficient tools to determine the minimum number of driving (or driven) nodes to steer a complex network towards a desired state. Furthermore, we often need to do it within a given time window, so it is of practical importance to understand the trade-offs between the minimum number of driving/driven nodes and the minimum time required to reach a desired state. Therefore, we introduce the notion of actuation spectrum to capture such trade-offs, which we used to find that in many complex networks only a small fraction of driving (or driven) nodes is required to steer the network to a desired state within a relatively small time window. Furthermore, our empirical studies reveal that, even though synthetic network models are designed to present structural properties similar to those observed in real networks, their actuation spectra can be dramatically different. Thus, it supports the need to develop new synthetic network models able to replicate controllability properties of real-world networks.

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Многоаспектность изучения языковой способности как психолингвистического феномена

Russkii iazyk za rubezhom ◽

10.37632/pi.2020.279.2.014 ◽

2020 ◽

Author(s):

O.A. Bezrukova

Keyword(s):

Cognitive Psychology ◽

Language Development ◽

Language Proficiency ◽

Scientific Knowledge ◽

Speech Therapy ◽

Practical Importance ◽

Scientific Data ◽

Structural Components ◽

Language Aptitude ◽

Language Pedagogy

В обзорной статье представлен феномен языковой способности человека с позиции различных областей научного знания: биологии, психофизиологии, лингводидактики, когнитивной психологии, логопедии. Автор сравнивает различные подходы к изучению генезиса и структурных составляющих данного феномена. Языковая способность рассматривается в трех основных значениях: как обучаемость (задатки), как процесс овладения языком (речевой онтогенез) и как обученность (результат).Выводы, полученные в результате аналитического осмысления научных данных, имеют важное прикладное значение для современной педагогики в целом и лингводидактики в частности.The review presents the phenomenon of a humans language capability from the standpoints of various fields of scientific knowledge: biology, psychophysiology, language pedagogy, cognitive psychology, speech therapy. The author compares the diverse approaches to the research of genesis and structural components of the phenomenon. Language capability is viewed as three basic definitions: as the ability to learn language (aptitude), as a process of language acquisition (language development), and as language proficiency (the result of learning). The conclusions obtained as a result of the analytical understanding of scientific data are of practical importance for comprehensive pedagogy in general and language pedagogy in particular.

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Thermodynamic effects after Diode and Er:YAG laser irradiation of grade IV and V titanium implants placed in bone – an ex vivo study. Preliminary report

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2015-0135 ◽

2016 ◽

Vol 61 (5) ◽

Cited By ~ 9

Author(s):

Jacek Matys ◽

Ute Botzenhart ◽

Tomasz Gedrange ◽

Marzena Dominiak

Keyword(s):

Chemical Composition ◽

Laser Power ◽

Ex Vivo ◽

Titanium Implants ◽

Implant Surface ◽

Laser Parameters ◽

Thermodynamic Effects ◽

Titanium Grade ◽

Time Required ◽

Ex Vivo Study

AbstractMany inserted implants are affected by peri-implantitis. The aim of our study was to evaluate increases in implant temperature, depending on the diameter and chemical composition of implants. In particular we measured the time it takes for the temperature of an implant to rise by 10°C and evaluated laser power settings required to prevent thermal injury when an implant surface is decontaminated during the treatment of peri-implantitis. The study analysed six implants placed in porcine ribs and divided into two groups according to their diameter and chemical composition (grade IV and grade V titanium). The implants were irradiated with Diode and Er:YAG lasers using different laser parameters. The temperature was measured with a K-type thermocouple. The temperature on the implant surface rose as the laser power increased and the implant diameter decreased. The time required to increase the temperature of an implant by 10°C was less than it was for titanium grade IV. The temperature gradient was below 10°C for all implants treated using a laser power up to 1 W. It is important to choose the correct laser parameters, depending on the chemical composition and diameter of the implant, so that decontamination of the implant surface is thorough, effective and safe.

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Triangular 3D Laser Scanning in Underwater Photogrammetry

Polish Hyperbaric Research ◽

10.1515/phr-2015-0015 ◽

2015 ◽

Vol 52 (3) ◽

pp. 35-44

Author(s):

Aleksander Wojtowicz ◽

Konrad Stolarczyk

Keyword(s):

Laser Scanning ◽

3D Model ◽

Accurate Information ◽

3D Laser Scanning ◽

Measured Object ◽

Photographic Documentation ◽

Good Measurement ◽

Time Required ◽

Similar Accuracy ◽

Measurement Practices

Abstract The use of triangular 3D laser scanning may significantly enhance the visual inspection of underwater objects. In these days of high demand for accurate information, exclusively photographic documentation is not enough, as it is geometrically flawed. The authors of this article are trying to present the rudiments of laser scanning, a modern means of measuring, which is reliable, relatively easy to use and works in accordance with basic good measurement practices. With the use of a laser beam, a point model of the measured object is generated with a resolution that is adapted to the requirements. A well performed scan will cover the entire surface of the measured object with no information gaps, as is often the case with photographic documentation which focuses solely on key details. Photographic documentation is now already being replaced by Structure from Motion technology, the latter being an alternative to laser scanning, which creates a textured 3D model from the collection of photographs of the object with similar accuracy, but with more time required.

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Complete Artificial Dentition Supported by Endosseous Implants: A Case Report of Total In-office Treatment

Journal of Oral Implantology ◽

10.1563/0-726.1 ◽

2005 ◽

Vol 31 (2) ◽

pp. 91-97

Author(s):

Dennis Flanagan

Keyword(s):

Case Report ◽

Titanium Implants ◽

Posterior Teeth ◽

Endosseous Implants ◽

Complete Restoration ◽

Occlusal Surfaces ◽

Medial Pterygoid ◽

Long Term Result ◽

Fixed Prosthesis

Abstract This case report demonstrates the construction of a complete restoration of the dentition by the surgical placement of endosseous titanium implants that support a fixed prosthesis in each jaw. The positioning of the implants and teeth in the prostheses are important factors for a successful long-term result. Distribution of the occlusal biting forces over as many implants as possible is important. Off-axial occlusal biting forces should be diverted to the anterior prostheses, where the forces are not as great and the posterior teeth are designed with flat occlusal surfaces that separate during excursionary chewing movements. Medial mandibular flexure caused by the contraction of the medial pterygoid muscle can be addressed by constructing the prosthesis in segments. This is so as not to have a rigid entity encased in flexing bone that may induce stress to the bone, leading to loss of implant integration and failure. Segmenting also insures an appropriate fit of the prosthesis with respect to casting and porcelain firing distortion. Lip support by means of a flange in the prosthesis may be necessary when there has been a large amount of bone loss from edentulous resorption. Cleaning and maintenance of the prostheses every 3 to 6 months is essential.

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Investigation of Temporal Bone Anatomy by Plastic Moulding and Cryomicrotomy

Acta Radiologica Diagnosis ◽

10.1177/028418518602700404 ◽

1986 ◽

Vol 27 (4) ◽

pp. 389-394 ◽

Cited By ~ 20

Author(s):

H. Wilbrand ◽

W. Rauschning

Keyword(s):

Temporal Bone ◽

Polyester Resin ◽

Plastic Material ◽

Three Dimensional ◽

Accurate Information ◽

Radiographic Images ◽

Cochlear Aqueduct ◽

Temporal Bone Anatomy ◽

Temporal Bones ◽

Bone Structures

To increase our understanding of the complex topographic relations between temporal bone structures and to facilitate the interpretation of their radiographic images, two techniques were developed. 1) Plastic moulding of temporal bone specimens using polyester resin and silicone rubber substances providing detailed information and a three-dimensional survey of the structures. Carefully macerated temporal bone specimens are filled with plastic material under vacuum and the bone is then dissolved. The preparations, freed from irrelevant structures and embellished, allow metric evaluation of the different structures and their topographic relations. 2) Automatic serial cryomicrotomy of fresh, deep-frozen temporal bones, using a commercial sledge-cryomicrotome. Photography of the cut surfaces of the specimen, usually at distances of 0.25 to 0.50 mm, allows natural-colour reproduction of minute detail, e.g. the melanin cell area in the cochlea, the smallest vessels on the ossicular surfaces, and the origin of the cochlear aqueduct at the basal turn of the cochlea. By correlating the photographs with images from the corresponding tomographic planes accurate information is obtained for interpretation of the radiographic images. A combination of the two techniques facilitates a detailed study and is a valuable aid in the teaching of temporal bone anatomy.

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Autologous platelets as a source of proteins for healing and tissue regeneration

Thrombosis and Haemostasis ◽

10.1160/th03-07-0440 ◽

2004 ◽

Vol 91 (01) ◽

pp. 4-15 ◽

Cited By ~ 755

Author(s):

Eduardo Anitua ◽

Isabel Andia ◽

Bruno Ardanza ◽

Paquita Nurden ◽

Alan Nurden

Keyword(s):

Growth Factors ◽

Tissue Regeneration ◽

Cosmetic Surgery ◽

Tendon Repair ◽

Fibrin Clot ◽

Positive Influence ◽

Titanium Implants ◽

Therapeutic Effects ◽

Active Metabolites ◽

Time Required

SummaryPlatelets are known for their role in haemostasis where they help prevent blood loss at sites of vascular injury. To do this, they adhere, aggregate and form a procoagulant surface leading to thrombin generation and fibrin formation. Platelets also release substances that promote tissue repair and influence the reactivity of vascular and other blood cells in angiogenesis and inflammation. They contain storage pools of growth factors including PDGF, TGF-β and VEGF as well as cytokines including proteins such as PF4 and CD40L. Chemokines and newly synthesised active metabolites are also released. The fact that platelets secrete growth factors and active metabolites means that their applied use can have a positive influence in clinical situations requiring rapid healing and tissue regeneration. Their administration in fibrin clot or fibrin glue provides an adhesive support that can confine secretion to a chosen site. Additionally, the presentation of growth factors attached to platelets and/or fibrin may result in enhanced activity over recombinant proteins. Dental implant surgery with guided bone regeneration is one situation where an autologous platelet-rich clot clearly accelerates ossification after tooth extraction and/or around titanium implants. The end result is both marked reductions in the time required for implant stabilisation and an improved success rate. Orthopaedic surgery, muscle and/or tendon repair, reversal of skin ulcers, hole repair in eye surgery and cosmetic surgery are other situations where autologous platelets accelerate healing. Our aim is to review these advances and discuss the ways in which platelets may provide such unexpected beneficial therapeutic effects.

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Accuracy of Bone Measurements in the Vicinity of Titanium Implants in CBCT Data Sets: A Comparison of Radiological and Histological Findings in Minipigs

BioMed Research International ◽

10.1155/2017/3848207 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Alexander Gröbe ◽

Jan Semmusch ◽

Maximilian Schöllchen ◽

Henning Hanken ◽

Michael Hahn ◽

...

Keyword(s):

Intraclass Correlation ◽

Random Effect ◽

Titanium Implants ◽

Data Sets ◽

Random Intercept ◽

Close Proximity ◽

Thin Bone ◽

The Difference ◽

Bone Structures

Purpose. The aim of this animal study was the determination of accuracy of bone measurements in CBCT (cone-beam computed tomography) in close proximity to titanium implants. Material and Methods. Titanium implants were inserted in eight Göttingen minipigs. 60 implants were evaluated histologically in ground section specimen and radiologically in CBCT in regard to thickness of the buccal bone. With random intercept models, the difference of histologic measurements and CBCT measurements of bone thickness was calculated. Results. The mean histological thickness of the buccal bone was 5.09 mm (CI 4.11–6.08 mm). The four raters measured slightly less bone in CBCT than it was found in histology. The random effect was not significant (p value 1.000). Therefore, the Intraclass Correlation Coefficient (ICC) was 98.65% (CI 100.00–96.99%). Conclusion. CBCT is an accurate technique to measure even thin bone structures in the vicinity of titanium implants.

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