scholarly journals Effect of an Er,Cr:YSGG Laser on the Surface of Implants: A Descriptive Comparative Study of 3 Different Tips and Pulse Energies

2020 ◽  
Vol 8 (4) ◽  
pp. 109
Author(s):  
Ehsan Chegeni ◽  
Antonio España-Tost ◽  
Rui Figueiredo ◽  
Eduard Valmaseda-Castellón ◽  
Josep Arnabat-Domínguez
Keyword(s):  
Dental Implants ◽  
In Vitro Study ◽  
Surface Damage ◽  
Sem Analysis ◽  
Implant Surface ◽  
Class A ◽  
Class D ◽  
Class B ◽  
Class C

Peri-implant diseases are one of the main complications of dental implants. There are no well-established guidelines regarding laser parameters for implant decontamination. The aim was to compare two different settings of irradiation of the Er,Cr:YSGG laser on dental implants regarding surface alterations and determine the best settings for less damage on the surface. An in vitro study was performed and 30 areas of dental implants were irradiated with two different regimes of energy per pulse 50 and 84 mJ (1.5 W/30 Hz and 2.5 W/30 Hz). A total of 30 sites of implants were irradiated with three different tips (10 surfaces per tip): conical (RTF3-17 mm), side firing (SFT8-18 mm) and cylindrical (MGG6-6 mm). The following descriptive classification on surface damage was employed: no damage (class A), minimal effects (class B), metal fall with melting (class C), and destruction with carbonization (class D). The assessment was made through a descriptive scanning electron microscope (SEM) analysis. Side firing and conical tips at 50 mJ were classified as class A. Side firing at 84 mJ and cylindrical tips 50 mJ and 84 mJ were classified as class B. Finally, class C defects were found in the areas where the conical tip was used at 84 mJ. Side firing and conical tips at 50 mJ do not seem to damage the implant surface.

Distribution of cortical granules in bovine oocytes classified by cumulus complex

Zygote ◽  
1997 ◽  
Vol 5 (4) ◽  
pp. 371-376 ◽  
Author(s):  
M. Hosoe ◽  
Y. shioya
Keyword(s):  
Type I ◽  
Cortical Granules ◽  
Type Iii ◽  
Class A ◽  
Class D ◽  
Class B ◽  
Cytoplasmic Maturation ◽  
Class C ◽  
Bovine Oocytes

SummaryThe present study was conducted to examine distributional changes of cortical granules(CGs)during meitotic maturation and fetilisation in vitro and the developmental ability in bovine oocytes classified by cumulus cells. The oocytes were classified by the morphology if their cumulus cell layers as follows: class A, compact and thick; class B, compact but thin; class C, naked; and class D, expanded. some of the oocytes were stained with Lens curinalis agglutinin(LCA) before and after maturation in vitro and after insemination, and then stained with orcein to observe their nuclear stages. The others were left in culture. Distributional patterns of the CGs were classified into four types: type I, CGs distributed in clusters; type II, CGs dispersed and partly clustered; type III, all CGs dispersed; and type IV, no CGs Most of the oocytes before culture showed a type I pattern, but this decreased after maturation culture, whereas type III increased in class A. The oocytes of class B showed similar changes while the oocytes of class C did not. In class C, many oocytes showed type I after culture indicating that cytoplasmic maturation was not completed. IN class D, 80.4% of the oocytes exhibited types III before maturation culture, indicating that their cytoplasmic maturation was different from classes A–C. and about 70% of the class D oocytes were at the unclear stage of germinal vesicle breakdown(GVBD) before culture. The developmental rates to blastocysts in classes A–D were 28.7%, 23.1%, 0.5% and 3.4% respectively.

scholarly journals Macrophagic Inflammatory Response Next to Dental Implants with Different Macro- and Micro-Structure: An In Vitro Study

2021 ◽  
Vol 11 (12) ◽  
pp. 5324
Author(s):  
Maria Menini ◽  
Francesca Delucchi ◽  
Domenico Baldi ◽  
Francesco Pera ◽  
Francesco Bagnasco ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Dental Implants ◽  
In Vitro Study ◽  
Titanium Implants ◽  
Implant Surface ◽  
Bone Implant ◽  
Optimal Outcomes ◽  
Negative Controls ◽  
Inflammatory Effect

(1) Background: Intrinsic characteristics of the implant surface and the possible presence of endotoxins may affect the bone–implant interface and cause an inflammatory response. This study aims to evaluate the possible inflammatory response induced in vitro in macrophages in contact with five different commercially available dental implants. (2) Methods: one zirconia implant NobelPearl® (Nobel Biocare) and four titanium implants, Syra® (Sweden & Martina), Prama® (Sweden & Martina), 3iT3® (Biomet 3i) and Shard® (Mech & Human), were evaluated. After 4 h of contact of murine macrophage cells J774a.1 with the implants, the total RNA was extracted, transcribed to cDNA and the gene expression of the macrophages was evaluated by quantitative PCR (qPCR) in relation to the following genes: GAPDH, YWHAZ, IL1β, IL6, TNFα, NOS2, MMP-9, MMP-8 and TIMP3. The results were statistically analyzed and compared with negative controls. (3) Results: No implant triggered a significant inflammatory response in macrophages, although 3iT3 exhibited a slight pro-inflammatory effect compared to other samples. (4) Conclusions: All the samples showed optimal outcomes without any inflammatory stimulus on the examined macrophagic cells.

scholarly journals In Vitro Activity of Cefiderocol against Multi-Drug Resistant Carbapenemase-Producing Gram-Negative Pathogens

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S376-S376 ◽  
Author(s):  
Sandra Boyd ◽  
Karen Anderson ◽  
Valerie Albrecht ◽  
Davina Campbell ◽  
Maria S Karlsson ◽  
...  
Keyword(s):  
Vitro Activity ◽  
Burkholderia Cepacia Complex ◽  
Uptake System ◽  
Drug Resistant ◽  
In Vitro Activity ◽  
Gram Negative ◽  
Class A ◽  
Class D ◽  
Class B

Abstract Background Few options remain for treatment of infections caused by multi-drug resistant (MDR), carbapenemase-producing gram-negative pathogens. Cefiderocol (CFDC; Shionogi & Co. Ltd), is a novel parenteral siderophore cephalosporin that enters the bacterial cell through the iron–siderophore uptake system. Here we report on the in vitro activity of CFDC against a set of well-characterized MDR gram-negative isolates collected by the Centers for Disease Control and Prevention. Methods Minimum inhibitory concentrations (MIC) values for CFDC in iron-depleted cation-adjusted Mueller Hinton broth were determined using reference broth microdilution. Study isolates (n = 315) included Enterobacteriaceae (59%), Pseudomonas aeruginosa (19%), Acinetobacter baumannii (17%), Stenotrophomonas maltophilia (4%), and Burkholderia cepacia complex (1%). Of these, 229 (73%) were carbapenemase-producers including Ambler Class A- (37%), Class B- (29%) and Class D- type (29%) enzymes. The remaining isolates included 51 β-lactam-resistant isolates that were non-carbapenemase-producers, and 35 β-lactam-susceptible isolates. Results were interpreted using suggested CFDC breakpoints of Sensitive ≤4 μg/mL and Resistant ≥16 μg/mL. Results The majority of the isolates (90.8%) were categorized as CFDC susceptible; the percentage of isolates with a CFDC MIC ≤4 μg/mL among Enterobacteriaceae, P. aeruginosa, and A. baumannii was 87.5%, 100%, and 89%, respectively. Percentage of isolates with a CFDC MIC ≤4 μg/mL that harbored a carbapenemase of the Class A-, Class B-, and Class D-type was 91.8%, 74.8%, 98.0%, respectively. By applying suggested breakpoints, 12 isolates were categorized as intermediate and 17 as resistant. The resistant isolates included 11 NDM-, 2 OXA-23- and 4 KPC-positive organisms. Conclusion Cefiderocol showed potent activity against MDR gram-negative pathogens including Class A, B, and D carbapenemase-producing isolates. Of note, all P. aeruginosa, including Class B metallo-β-lactamase producers, were susceptible to CFDC. Disclosures All authors: No reported disclosures.

scholarly journals Interaction between Different Implant Surfaces and Liquid Fibrinogen: A Pilot In Vitro Experiment

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Catherine X. Andrade ◽  
Marc Quirynen ◽  
David R. Rosenberg ◽  
Nelson R. Pinto
Keyword(s):  
Dental Implants ◽  
Healing Process ◽  
In Vitro Study ◽  
Initial Contact ◽  
Implant Surface ◽  
Oral Surgical Procedures ◽  
Healthy Donors ◽  
Lower Blood ◽  
Fibrin Network

Background. Platelet concentrates like leucocyte- and platelet-rich fibrin (L-PRF) have been widely evaluated in different oral surgical procedures to promote the healing process. However, liquid L-PRF products such as liquid fibrinogen have been poorly explored, especially in the biomimetic functionalization of dental implants. The aim of this in vitro study is to evaluate the interaction between 5 different dental implant surfaces and liquid fibrinogen. Methods. Five commercially available dental implants with different surfaces (Osseospeed™, TiUnite™, SLActive®, Ossean®, and Plenum®) were immersed for 60 minutes in liquid fibrinogen obtained from healthy donors. After this period, the implants were removed and fixed for scanning electron microscopy (SEM). Results. All dental implants were covered by a fibrin mesh. However, noticeable noncontact areas were observed for the Osseospeed™, TiUnite™, and SLActive® surfaces. On the other hand, Ossean® and Plenum® surfaces showed a dense and uniform layer of fibrin covering almost the entire implant surface. The Osseospeed™, TiUnite™, and SLActive® surfaces presented with lower blood cell numbers inside the fibrin mesh compared with the others. Moreover, at higher magnification, thicker fibrin fibers were observed in contact with Ossean® and Plenum® surfaces. The Plenum ®surface showed the thickest fibers which also inserted and interconnect to the microroughness. Conclusion. The initial contact between an implant surface and the fibrin network differs significantly among different implant brands. Further studies are necessary to explore the clinical impact of these observations in the osseointegration process of dental implants.

scholarly journals In Vitro and In Vivo Activities of AM-112, a Novel Oxapenem

2003 ◽  
Vol 47 (5) ◽  
pp. 1652-1657 ◽  
Author(s):  
Conor E. Jamieson ◽  
Peter A. Lambert ◽  
Iain N. Simpson
Keyword(s):  
Clavulanic Acid ◽  
Enterobacter Cloacae ◽  
Penicillin Binding Proteins ◽  
Class A ◽  
Sepsis Model ◽  
Class D ◽  
Class C ◽  
Lactamase Inhibitor

ABSTRACT AM-112 [(1′R,5R,6R)-3-(4-amino-1,1-dimethyl-butyl)-6-(1′-hydroxyethyl)oxapenem-3-carboxylate] is a novel oxapenem compound which possesses potent β-lactamase-inhibitory properties. Fifty-percent inhibitory concentrations (IC50s) of AM-112 for class A enzymes were between 0.16 and 2.24 μM for three enzymes, compared to IC50s of 0.008 to 0.12 μM for clavulanic acid. Against class C and class D enzymes, however, the activity of AM-112 was between 1,000- and 100,000-fold greater than that of clavulanic acid. AM-112 had affinity for the penicillin-binding proteins (PBPs) of Escherichia coli DC0, with PBP2 being inhibited by the lowest concentration of AM-112 tested, 0.1 μg/ml. Ceftazidime was combined with AM-112 at 1:1 and 2:1 ratios in MIC determination studies against a panel of β-lactamase-producing organisms. These studies demonstrated that AM-112 was effective at protecting ceftazidime against extended-spectrum β-lactamase-producing strains and derepressed class C enzyme producers, reducing ceftazidime MICs by 16- and 2,048-fold. Similar results were obtained when AM-112 was combined with ceftriaxone, cefoperazone, or cefepime in a 1:2 ratio. Protection of ceftazidime with AM-112 was maintained against Enterobacter cloacae P99 and Klebsiella pneumoniae SHV-5 in a murine intraperitoneal sepsis model. The 50% effective dose of ceftazidime against E. cloacae P99 and K. pneumoniae SHV-5 was reduced from >100 and 160 mg/kg of body weight to 2 and 33.6 mg/kg, respectively, when it was combined with AM-112 at a 1:1 ratio. AM-112 demonstrates potential as a new β-lactamase inhibitor.

IN VITRO STUDY AND MECHANICAL CHARACTERISTICS OF DENTAL IMPLANTS MADE OF VARIOUS MATERIALS AND FABRICATION METHODS

2021 ◽  
Vol 21 (01) ◽  
pp. 2150004
Author(s):  
MEHDI MASHHADI ◽  
REZA HAMZELOO ◽  
MEGHDAD FALLAH
Keyword(s):  
Dental Implants ◽  
Surface Hardness ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Topology Design ◽  
In Vitro Tests ◽  
Implant Surface ◽  
Experimental Surface ◽  
Hardness Values

Selecting materials and alloys, fabrication methods, surface characteristics and coatings, and topology design, all affect the mechanical properties, biocompatibility, and functionality of dental implants. The success in embedding implants in mouth and improving biocompatibility and consequently useful life of implants depends directly on proper adhesion of tissue to implant surface of a biocompatible alloy. In this research, experimental surface hardness and in vitro tests are carried out on samples with different alloys and different manufacturing methods. Various fabrication techniques, such as machining and 3D printing (Selective laser melting (SLM)), are considered for steel and titanium specimens. Results show that the hardness values of specimens made by the SLM method are higher than machined samples about 8% and also stainless steels samples have higher hardness than titanium specimens. A comparison of scanning electron microscopy (SEM) surface pictures indicates that applying modern fabrication methods for production which includes SLM improves the performance of implants in terms of mechanical and biocompatibility by increasing cell adhesion up to 21 times. In addition, results indicate that titanium alloys have almost 13% higher adhesion property than stainless steel and generally exhibit a higher balance of adhesion and cell growth.

Durability of hearing preservation after microsurgical treatment of vestibular schwannoma using the middle cranial fossa approach

2013 ◽  
Vol 119 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Anthony C. Wang ◽  
Steven B. Chinn ◽  
Khoi D. Than ◽  
H. Alexander Arts ◽  
Steven A. Telian ◽  
...  
Keyword(s):  
Facial Nerve ◽  
Hearing Preservation ◽  
Middle Cranial Fossa ◽  
Nerve Function ◽  
Facial Nerve Function ◽  
Class A ◽  
Class D ◽  
Class B ◽  
Class C

Object The middle cranial fossa (MCF) approach is a microsurgical technique described as a primary option in the treatment of small, intracanalicular schwannomas involving the eighth cranial nerve. Excellent rates of complete tumor resection, hearing preservation, preservation of facial nerve function, and low complication rates have been reproduced using this technique. However, the durability of hearing preservation attained using the various treatment options has not been adequately assessed. The purpose of this study was to evaluate the durability of long-term hearing preservation in patients with vestibular schwannoma (VS) treated via the MCF approach. The authors hypothesize that hearing preservation in these patients will prove to be durable years after treatment in a high percentage of cases. Methods Retrospective medical chart review was performed in 103 consecutive patients undergoing resection of VS via a modified MCF approach between 1999 and 2008. Patients in whom surgical goals were gross-total resection and hearing preservation were included. Preoperative and postoperative hearing assessment was performed using standard audiometric testing, and classified according to American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) guidelines as a primary outcome measure. Outcomes and neurological complications initially, and at 1, 3, and 5 years following operation were analyzed. Results Initial hearing preservation rates were in keeping with the best previously published results. At initial postoperative audiometric follow-up, of the patients presenting with Class A hearing, 67% remained Class A, 17% were Class B, 1% were Class C, and 15% were Class D. Of patients presenting with Class B hearing, 24% were Class A, 53% remained Class B, 6% were Class C, and 18% were Class D. Of patients presenting with Class C hearing, 100% remained Class C. To assess the durability of hearing preservation in our patients, the authors evaluated hearing function at regular intervals after the initial postoperative audiometric follow-up. Audiometric data were available for 56 patients at 5-year follow-up. Of the 20 patients with Class A hearing at initial postoperative follow-up with 5-year follow-up, 13 (65%) remained Class A, 6 (30%) were Class B, and 1 (5%) was Class C. Of the 12 patients with Class B hearing at initial postoperative follow-up with 5-year follow-up, 4 (33%) were Class A, 4 (33%) remained Class B, and 4 (33%) were Class C. Of the 3 patients with Class C hearing at initial postoperative follow-up with 5-year follow-up, all 3 (100%) remained Class C. Conclusions A majority of patients with preserved hearing following the MCF approach for treatment of VS experience durability of their preserved hearing at 5-year follow-up. The initial AAO-HNS classification was preserved in 13 (65%) of the 20 patients who had Class A hearing at 5 years, and in 8 (67%) of the 12 who had Class B hearing at 5 years. Overall, a decline in AAO-HNS classification was noted in 15% of patients with preserved Class A hearing, and in 33% of those with preserved Class B hearing. Facial nerve function was preserved in 91% of cases. Superior hearing preservation as well as good outcomes in facial nerve function and few serious complications can be accomplished using the MCF approach for resection of small VSs.

scholarly journals Dexamethasone prevents relapse after emergency department treatment of acute migraine: a randomized clinical trial

CJEM ◽  
1999 ◽  
Vol 1 (01) ◽  
pp. 26-33 ◽  
Author(s):  
Grant D. Innes ◽  
Iain Macphail ◽  
Edward C. Dillon ◽  
Cathy Metcalfe ◽  
Min Gao
Keyword(s):  
Emergency Department ◽  
Initial Treatment ◽  
Physician Visit ◽  
Recurrent Headache ◽  
Class A ◽  
Headache Severity ◽  
Class D ◽  
Class B ◽  
Class C

ABSTRACT:Objective:To determine whether the addition of intravenous dexamethasone to standard emergency department (ED) migraine therapy would decrease the incidence of severe recurrent headache 24 to 48 hours after initial treatment.Methods:Patients aged 19 to 65 years whose headache was severe enough to require parenteral therapy and who met International Headache Society migraine criteria were eligible for this randomized, double-blind trial. The study was conducted in the ED of 2 community hospitals, 1 of which was a tertiary referral centre. Exclusion criteria included pregnancy, focal findings, fever, meningismus, allergy to the study drug, active peptic ulcer disease and diabetes mellitus. Demographic and clinical data, including headache severity, were recorded. After abortive therapy (antiemetics, intravenous nonsteroidal agents, dihydroergotamine or opioids), blinded nurses administered dexamethasone (24 mg intravenously) or placebo. Patients recorded headache severity on a Visual Analogue Scale (VAS) at time T = 0, T = 30 minutes and T = 60 minutes and at discharge. They were contacted 48 to 72 hours later and asked whether they had suffered a recurrence of their headache, categorized as class A (severe, provoking another physician visit), class B (severe, interfering with daily activity but not provoking a physician visit), class C (mild, requiring self-medication but not limiting activity) or class D (mild, requiring no treatment). Results: Two of 100 patients were lost to follow-up, leaving 98 in the study sample. Placebo recipients were more likely to be female; other baseline characteristics were similar between groups. Median VAS pain score was 83 mm on ED arrival, 35 mm after initial treatment and 12 mm on discharge. At follow-up, 65 of 98 patients had suffered headache recurrence. In the placebo versus dexamethasone groups, respectively, the results were 11 versus 0 in class A, 11 versus 9 in class B, 7 versus 11 in class C and 4 versus 12 in class D. Regarding the primary outcome, 9 of 49 dexamethasone patients (18%) and 22 of 49 placebo patients (45%) had severe (classes A and B) recurrent headache (odds ratio 0.28; 95% CI, 0.11 to 0.69;p= 0 .005).Conclusions:Migraine recurrence is common after “successful” ED treatment. Inflammation may be a critical factor in migraine genesis. Intravenous dexamethasone decreases the incidence of severe recurrent headache after ED treatment and should be offered to patients thought to be at risk of recurrent headache.

scholarly journals Particle release from implantoplasty of dental implants and impact on cells

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Fadi N. Barrak ◽  
Siwei Li ◽  
Albert M. Muntane ◽  
Julian R. Jones
Keyword(s):  
Dental Implants ◽  
Inductively Coupled Plasma ◽  
In Vitro Study ◽  
Optical Emission ◽  
Systemic Effect ◽  
Implant Surface ◽  
Inductively Coupled ◽  
Materials Used ◽  
The Individual

Abstract Background With increasing numbers of dental implants placed annually, complications such as peri-implantitis and the subsequent periprosthetic osteolysis are becoming a major concern. Implantoplasty, a commonly used treatment of peri-implantitis, aims to remove plaque from exposed implants and reduce future microbial adhesion and colonisation by mechanically modifying the implant surface topography, delaying re-infection/colonisation of the site. This in vitro study aims to investigate the release of particles from dental implants and their effects on human gingival fibroblasts (HGFs), following an in vitro mock implantoplasty procedure with a diamond burr. Materials and methods Commercially available implants made from grade 4 (commercially pure, CP) titanium (G4) and grade 5 Ti-6Al-4 V titanium (G5) alloy implants were investigated. Implant particle compositions were quantified by inductively coupled plasma optical emission spectrometer (ICP-OES) following acid digestion. HGFs were cultured in presence of implant particles, and viability was determined using a metabolic activity assay. Results Microparticles and nanoparticles were released from both G4 and G5 implants following the mock implantoplasty procedure. A small amount of vanadium ions were released from G5 particles following immersion in both simulated body fluid and cell culture medium, resulting in significantly reduced viability of HGFs after 10 days of culture. Conclusion There is a need for careful evaluation of the materials used in dental implants and the potential risks of the individual constituents of any alloy. The potential cytotoxicity of G5 titanium alloy particles should be considered when choosing a device for dental implants. Additionally, regardless of implant material, the implantoplasty procedure can release nanometre-sized particles, the full systemic effect of which is not fully understood. As such, authors do not recommend implantoplasty for the treatment of peri-implantitis.

scholarly journals Kinetics of Sulbactam Hydrolysis by β-Lactamases, and Kinetics of β-Lactamase Inhibition by Sulbactam

2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Adam B. Shapiro
Keyword(s):  
Molar Ratio ◽  
Inactivation Kinetics ◽  
High Turnover ◽  
Content Type ◽  
Class A ◽  
Class D ◽  
Class B ◽  
Class C ◽  
Kinetics Of ◽  
Enzyme Class

ABSTRACT Sulbactam is one of four β-lactamase inhibitors in current clinical use to counteract drug resistance caused by degradation of β-lactam antibiotics by these bacterial enzymes. As a β-lactam itself, sulbactam is susceptible to degradation by β-lactamases. I investigated the Michaelis-Menten kinetics of sulbactam hydrolysis by 14 β-lactamases, representing clinically widespread groups within all four Ambler classes, i.e., CTX-M-15, KPC-2, SHV-5, and TEM-1 for class A; IMP-1, NDM-1, and VIM-1 for class B; Acinetobacter baumannii ADC-7, Pseudomonas aeruginosa AmpC, and Enterobacter cloacae P99 for class C; and OXA-10, OXA-23, OXA-24, and OXA-48 for class D. All of the β-lactamases were able to hydrolyze sulbactam, although they varied widely in their kinetic constants for the reaction, even within each class. I also investigated the inactivation kinetics of the inhibition of these enzymes by sulbactam. The class A β-lactamases varied widely in their susceptibility to inhibition, the class C and D enzymes were very weakly inhibited, and the class B enzymes were essentially or completely unaffected. In addition, we measured the sulbactam turnover number, the sulbactam/enzyme molar ratio required for complete inhibition of each enzyme. Class C enzymes had the lowest turnover numbers, class A enzymes varied widely, and class D enzymes had very high turnover numbers. These results are valuable for understanding which β-lactamases ought to be well inhibited by sulbactam. Moreover, since sulbactam has intrinsic antibacterial activity against Acinetobacter species pathogens, these results contribute to understanding β-lactamase-mediated sulbactam resistance in Acinetobacter, especially due to the action of the widespread class D enzymes.

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