Publications by authors named "Gianluca Turco"

51 Publications

Trabecular bone porosity and pore size distribution in osteoporotic patients - A low field nuclear magnetic resonance and microcomputed tomography investigation.

J Mech Behav Biomed Mater 2022 01 29;125:104933. Epub 2021 Oct 29.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, I-34149, Trieste, Italy.

The study of bone morphology is of great importance as bone morphology is influenced by factors such as age and underlying comorbidities and is associated with bone mechanical properties and fracture risk. Standard diagnostic techniques used in bone disease, such as Dual-Energy X-ray absorptiometry and ultrasonography do not provide qualitative and quantitative morphological information. In recent years, techniques such as High Resolution Computed Tomography (HR-CT), micro- CT, Magnetic Resonance Imaging (MRI), and Low Field Nuclear Magnetic Resonance (LF-NMR) have been developed for the study of bone structure and porosity. Data obtained from these techniques have been used to construct models to predict bone mechanical properties thanks to finite element analysis. Cortical porosity has been extensively studied and successfully correlated with disease progression and mechanical properties. Trabecular porosity and pore size distribution, however, have increasingly been taken into consideration to obtain a comprehensive analysis of bone pathology and mechanic. Therefore, we have decided to evaluate the ability of micro- CT (chosen for its high spatial resolving power) and LF-NMR (chosen to analyze the behavior of water molecules within trabecular bone pores) to characterize the morphology of trabecular bone in osteoporosis. Trabecular bone samples from human femoral heads collected during hip replacement surgery were from osteoporosis (test group) and osteoarthritis (control group) patients. Our data show that both micro- CT and LF-NMR can detect qualitative changes in trabecular bone (i.e., transition from plate-like to rod-like morphology). Micro- CT failed to detect significant differences in trabecular bone morphology parameters between osteoporotic and osteoarthritic specimens, with the exception of Trabecular Number and Connectivity Density, which are markers of osteoporosis progression. In contrast, LF-NMR was able to detect significant differences in porosity and pore size of trabecular bone from osteoporotic versus osteoarthritic (control) samples. However, only the combination of these two techniques allowed the detection of structural morphometric changes (increase in the larger pore fraction and enlargement of the larger pores) in the trabecular bone of osteoporotic specimens compared to osteoarthritic ones. In conclusion, the combined use of LF-NMR and micro- CT provides a valuable tool for characterizing the morphology of trabecular bone and may offer the possibility for a new approach to the study and modeling of bone mechanics in the context of aging and disease.
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http://dx.doi.org/10.1016/j.jmbbm.2021.104933DOI Listing
January 2022

Chairside CAD/CAM Materials: Current Trends of Clinical Uses.

Biology (Basel) 2021 Nov 12;10(11). Epub 2021 Nov 12.

Department of Medical, Surgical, and Health Sciences, University of Trieste, 34127 Trieste, Italy.

Restorative materials are experiencing an extensive upgrade thanks to the use of chairside Computer-aided design/computer-assisted manufacturing (CAD/CAM) restorations. Therefore, due to the variety offered in the market, choosing the best material could be puzzling for the practitioner. The clinical outcome of the restoration is influenced mainly by the material and its handling than by the fabrication process (i.e., CAD/CAM). Information on the restorative materials performances can be difficult to gather and compare. The aim of this article is to provide an overview of chairside CAD/CAM materials, their classification, and clinically relevant aspects that enable the reader to select the most appropriate material for predictable success.
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http://dx.doi.org/10.3390/biology10111170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8614873PMC
November 2021

Profile of a new extended range-of-vision IOL: a laboratory study.

Graefes Arch Clin Exp Ophthalmol 2021 Oct 4. Epub 2021 Oct 4.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.

Purpose: To evaluate the surface profile of a new-generation extended range-of-vision intraocular lens (IOL) and to compare it with that obtained for a monofocal IOL based on the same platform.

Methods: Prospective, experimental, laboratory study comparing the surface profile of the DFT015 (AcrySof IQ Vivity; Alcon Laboratories, Inc.), a new-generation presbyopia-correcting IOL, with the profile of the SN60WF (AcrySof IQ; Alcon Laboratories, Inc.), an aspheric monofocal IOL based on the same platform. Raw profiles were obtained using contact profilometry. The best-fit form was then subtracted from each raw profile to highlight potential differences.

Results: No significant differences were appreciated in raw profiles. On the contrary, after form removal, the new extended range-of-vision IOL showed a peculiar profile characterized by the presence of two altitudinal symmetrical changes in the order of 1 µm, localized in the central portion of the optic.

Conclusions: The new-generation extended range-of-vision IOL evaluated showed a smooth change of its surface compared to the same platform monofocal IOL. The altitudinal changes blended in the central design of the new presbyopia-correcting IOL, although micrometric, might play a crucial role in creating a continuous focal range while minimizing visual disturbances.
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http://dx.doi.org/10.1007/s00417-021-05426-3DOI Listing
October 2021

Alginate bone scaffolds coated with a bioactive lactose modified chitosan for human dental pulp stem cells proliferation and differentiation.

Carbohydr Polym 2021 Dec 27;273:118610. Epub 2021 Aug 27.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Piazza dell'Ospitale 1, 34125 Trieste, Italy. Electronic address:

Bioactive and biodegradable porous scaffolds can hasten the healing of bone defects; moreover, patient stem cells seeded onto scaffolds can enhance the osteoinductive and osteoconductive properties of these biomaterials. In this work, porous alginate/hydroxyapatite scaffolds were functionalized with a bioactive coating of a lactose-modified chitosan (CTL). The highly interconnected porous structure of the scaffold was homogeneously coated with CTL. The scaffolds showed remarkable stability up to 60 days of aging. Human Dental Pulp Stem Cells (hDPSCs) cultured in the presence of CTL diluted in culture medium, showed a slight and negligible increase in terms of proliferation rate; on the contrary, an effect on osteogenic differentiation of the cells was observed as a significant increase in alkaline phosphatase activity. hDPSCs showed higher cell adhesion on CTL-coated scaffolds than on uncoated ones. CTL coating did not affect cell proliferation, but stimulated cell differentiation as shown by alkaline phosphatase activity analysis.
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http://dx.doi.org/10.1016/j.carbpol.2021.118610DOI Listing
December 2021

Ultrasonic Instrument Effects on Different Implant Surfaces: Profilometry, Energy-Dispersive X-ray Spectroscopy, and Microbiology In Vitro Study.

Int J Oral Maxillofac Implants 2021 May-Jun;36(3):520-528

Purpose: To assess the effects of grade IV titanium ultrasonic tip instrumentation on different grade IV titanium implant surfaces and compare the decontamination of different implant surfaces using chlorhexidine, blue laser, or ozone.

Materials And Methods: Profilometry and energy-dispersive x-ray spectroscopy (EDS) analyses were performed on smooth, laser-micropatterned, and sandblasted grade IV titanium sample disks before (t) and after (t) ultrasonic instrumentation with an ultrasonic grade IV titanium tip. Samples were also incubated with a Streptococcus sanguinis culture. Each surface type was then treated with chlorhexidine, blue laser, or ozone (three test groups + control group). Scanning electron microscopy (SEM) images were taken after bacterial growth and after decontamination.

Results: After ultrasonic instrumentation, surface roughness (R) decreased on sandblasted and micropatterned surfaces, whereas it remained substantially unvaried on the smooth surface. SEM images revealed that the laser-micropatterned structure remained substantially unvaried after instrumentation. EDS revealed a minimal quantity of carbon and iron, found in the laser-treated and sandblasted group at t0. A minimal quantity of aluminum and oxygen was found on the sandblasted surface at t and t. Ozone therapy achieved the highest decontaminating effect, regardless of implant surface topography.

Conclusion: Among the alternative therapies to ultrasonic instrumentation with titanium tips, ozone appears to be effective regardless of the type of implant surface; it can be used for the decontamination treatment of implants without altering the surface structure.
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http://dx.doi.org/10.11607/jomi.8140DOI Listing
June 2021

Development of di-methacrylate quaternary ammonium monomers with antibacterial activity.

Acta Biomater 2021 07 20;129:138-147. Epub 2021 May 20.

University of Trieste, Department of Medical Sciences; Institute for Maternal and Child Health Burlo Garofolo, Via dell'Istria, 65, 34137, Trieste, Italy. Electronic address:

Nine antibacterial di-methacrylate monomers based on bis-quaternary ammonium salts (bis-QAMs) were synthesized and structurally characterized. The biological activity of the bis-QAMs was tested in terms of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) on different bacterial strains achieving promising results and, in most cases, a complete bactericidal effect using a bis-QAM concentration lower than 1 mg/mL. Two of the structures showed comparable and superior activity against S. mutans than the commercial monomer 12-methacryloyloxydodecyl pyridinium bromide (MDBP). All the bis-QAMs here described were able to inhibit S. mutans biofilm formation at a concentration equal to the MIC value. From the analysis of the obtained data, some correlation regarding the structure and the antibacterial activity of the bis-QAMs could be drawn: a flexible alkyl C spacer between the two quaternary ammonium moieties increased the monomer antibacterial effect in comparison to the aromatic ones; the equilibrium between hydrophobic and hydrophilic moieties was directly correlated to the bactericidal range of action; the increase of the steric hindrance of the ammonium side groups might be both advantageous or disadvantageous to the antibacterial efficacy depending on the whole monomer chemical structure. Even though the possible correlation between the monomer structures and their bacteriostatic or bactericidal effect is under investigation, the monomers exhibited low cytotoxicity on human dental pulp stem cells, confirming their promising potential in the dental materials' field. STATEMENT OF SIGNIFICANCE: The use of dental resins with antibacterial monomers might prevent the formation of secondary caries at the restoration margins. For this purpose, a series of di-methacrylate bis-quaternary ammonium monomers (QAMs) was developed. Unlike antibacterial mono-methacrylate monomers already described in the literature, the synthesized di-methacrylate monomers have the potential of acting as cross-linkers stabilizing the polymeric network and bear two quaternary ammonium groups that increase their antibacterial ability. The QAMs exert bactericidal activity on both Gram(+) and Gram(-) bacterial strains maintaining at the same time good biocompatibility with the oral environment. Some structural elements of the monomers were clearly related to high antibacterial properties, and this can help design new active structures and better understand their mechanism of action.
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http://dx.doi.org/10.1016/j.actbio.2021.05.012DOI Listing
July 2021

Antibacterial Electrospun Polycaprolactone Membranes Coated with Polysaccharides and Silver Nanoparticles for Guided Bone and Tissue Regeneration.

ACS Appl Mater Interfaces 2021 Apr 6;13(15):17255-17267. Epub 2021 Apr 6.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Piazza dell'Ospitale 1, 34129 Trieste, Italy.

Electrospun polycaprolactone (PCL) membranes have been widely explored in the literature as a solution for several applications in tissue engineering and regenerative medicine. PCL hydrophobicity and its lack of bioactivity drastically limit its use in the medical field. To overcome these drawbacks, many promising strategies have been developed and proposed in the literature. In order to increase the bioactivity of electrospun PCL membranes designed for guided bone and tissue regeneration purposes, in the present work, the membranes were functionalized with a coating of bioactive lactose-modified chitosan (CTL). Since CTL can be used for the synthesis and stabilization of silver nanoparticles, a coating of this compound was employed here to provide antibacterial properties to the membranes. Scanning electron microscopy imaging revealed that the electrospinning process adopted here allowed us to obtain membranes with homogeneous fibers and without defects. Also, PCL membranes retained their mechanical properties after several weeks of aging in simulated body fluid, representing a valid support for cell growth and tissue development. CTL adsorption on membranes was investigated by fluorescence microscopy using fluorescein-labeled CTL, resulting in a homogeneous and slow release over time. Inductively coupled plasma-mass spectrometry was used to analyze the release of silver, which was shown to be stably bonded to the CTL coating and to be slowly released over time. The CTL coating improved MG63 osteoblast adhesion and proliferation on membranes. On the other hand, the presence of silver nanoparticles discouraged biofilm formation by and without being cytotoxic. Overall, the stability and the biological and antibacterial properties make these membranes a valid and versatile material for applications in guided tissue regeneration and in other biomedical fields like wound healing.
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http://dx.doi.org/10.1021/acsami.1c01016DOI Listing
April 2021

In vitro study on conditioned dental root surfaces: evaluation of wettability, smear layer, and blood clot adhesion.

Quintessence Int 2021 Jun;52(7):624-634

Objectives: The aim was to investigate the efficacy of citric acid and ethylenediaminetetraacetic acid (EDTA)-based treatments on smear layer removal and blood clot formation and stabilization.

Method And Materials: After scaling and root planing, 126 root samples were divided into seven groups treated with: deionized water; saline; citric acid solution; Ultradent Citric Acid gel; EDTA solution; EDTA-based PrefGel; or untreated. Each group was divided into three subgroups: I for the evaluation of smear layer removal and surface wettability, II and III for the evaluation of blood clot formation and stabilization in static or dynamic rinsing conditions.

Results: Conditioning agent treatments increased surface wettability with respect to untreated samples (Ultradent: 45 ± 1 degrees, P = 6.2 × 10-3; EDTA: 36 ± 5 degrees, P = 8.9 × 10-7; PrefGel: 47 ± 7 degrees, P = 3.2 × 10-2). Smear layer removal (30% to 60% with respect to untreated samples) was observed for all the conditioning agents. Clot was absent on untreated samples and samples treated with deionized water. Clot quality was significantly higher for samples treated with conditioning agents (P < .05) and similar between group II and III (P > .05). A statistically significant difference (P = .027) was observed for clot coverage of the saline group, comparing static and dynamic rinsing, confirming the positive effect of treatments on clot stabilization.

Conclusions: The use of conditioning agents improves smear layer removal and clot formation and stabilization with respect to scaling and root planing procedure only, which is, however, considered an essential procedure to promote wound healing in periodontal surgery.
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http://dx.doi.org/10.3290/j.qi.b1044167DOI Listing
June 2021

Mechanical Evaluation of the Stability of One or Two Miniscrews under Loading on Synthetic Bone.

J Funct Biomater 2020 Nov 5;11(4). Epub 2020 Nov 5.

Department of Medical, Surgical and Health Sciences, University of Trieste, 34127 Trieste, Italy.

The aim of the present study was to evaluate the primary stability of a two-miniscrew system inserted into a synthetic bone and to compare the system with the traditional one. Forty-five bi-layered polyurethane blocks were used to simulate maxillary cancellous and cortical bone densities. Samples were randomly assigned to three groups-one-miniscrew system (Group A, = 23), two-miniscrew system (Group B, = 22) and archwire-only (Group C, = 10). A total of 67 new miniscrews were subdivided into Group A (23 singles) and Group B (22 couples). 30 mm of 19″ × 25″ archwires were tied to the miniscrew. The load was applied perpendicularly to the archwire. Maximum Load Value (MLV), Yield Load (YL) and Loosening Load (LL) were recorded for each group. The YL of Group B and C had a mean value respectively of 4.189 ± 0.390 N and 3.652 ± 0.064 N. The MLV of Group A, B and C had a mean value respectively of 1.871 ± 0.318N, of 4.843 ± 0.515 N and 4.150 ± 0.086 N. The LL of Group A and B had a mean value respectively of 1.871 ± 0.318 N and of 2.294 ± 0.333 N. A two- temporary anchorage device (TAD) system is on average stiffer than a one-TAD system under orthodontic loading.
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http://dx.doi.org/10.3390/jfb11040080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711976PMC
November 2020

Comparative analysis of 23-, 25-, and 27-gauge forceps stiffness and related displacement.

Eur J Ophthalmol 2021 May 27;31(3):1313-1319. Epub 2020 May 27.

Department of Medical Surgical Sciences and Health, Eye Clinic, University of Trieste, Trieste, Italy.

Purpose: To test the stiffness and displacement of different vitreous forceps. Physical features and deformation after multiple procedures were also measured.

Methods: Eleven different 23-, 25-, and 27-gauge vitreous forceps were studied. The measurements were repeated loading the probe at different distances from the tip: at the top of the tip and 10 and 20 mm from the tip, respectively. For each probe, 10 successive identical bending tests were performed. The total length and the internal and external diameters of each forceps were also measured.

Results: A total of 330 successive identical bending tests were performed. No progression in deformation after the repeated measurements was recorded ( > 0.05). In each gauge group, displacement differences were detected according to the manufacturing metal properties, the total length, and the thickness of the shaft wall. A minimal adequate model to describes forceps displacements in terms of their significant predictors, such as gauge, model, and load distance from the tip, was created.

Conclusion: We provided a precise assessment of the stiffness and displacement of different vitreous forceps to enable surgeons to select the optimal instrument according to the benefits and limitations of each forceps.
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http://dx.doi.org/10.1177/1120672120926861DOI Listing
May 2021

Surface profiles of new-generation IOLs with improved intermediate vision.

J Cataract Refract Surg 2020 Jun;46(6):902-906

From the Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.

Purpose: To evaluate the surface profile of different new-generation intraocular lenses (IOLs) designed to improve intermediate vision.

Setting: Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.

Design: Prospective experimental laboratory study.

Methods: One higher-order aspheric monofocal IOL (Tecnis Eyhance ICB00) and 2 extended depth-of-focus (EDOF) IOLs (Tecnis Symfony ZXR00, Mini Well Ready) were examined and compared with monofocal IOLs with the same platform (Sensar AAB00, Tecnis ZCB00, Mini 4 Ready) using contact profilometry. Raw profiles were obtained and compared. The best-fit circle was then subtracted from each raw profile to highlight differences.

Results: The new higher-order aspheric IOL presented a peculiar profile, which appeared similar to the conventional monofocal IOL based on the same platform, with just minimal differences in the central design. One of the EDOF IOLs showed a diffractive design. The EDOF IOL based on spherical aberration presented a central steepening surrounded by a symmetric lateral change in depths.

Conclusions: Improved intermediate vision can be achieved by means of different optic designs. Unlike the traditional EDOF and multifocal IOLs based on a diffractive design, the profiles of new-generation IOLs are characterized by smooth and progressive changes of the superficial geometry.
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http://dx.doi.org/10.1097/j.jcrs.0000000000000215DOI Listing
June 2020

A Critical Review on the Production of Electrospun Nanofibres for Guided Bone Regeneration in Oral Surgery.

Nanomaterials (Basel) 2019 Dec 19;10(1). Epub 2019 Dec 19.

Clinical Department of Medical, Surgical and Health Sciences, University of Trieste, 34100 Trieste, Italy.

Nanofibre-based membranes or scaffolds exhibit high surface-to-volume ratio, which allows an improved cell adhesion, representing an attractive subgroup of biomaterials due to their unique properties. Among several techniques of nanofiber production, electrospinning is a cost-effective technique that has been, to date, attractive for several medical applications. Among these, guided bone regeneration is a surgical procedure in which bone regeneration, due to bone atrophy following tooth loss, is "guided" by an occlusive barrier. The membrane should protect the initial blood clot from any compression, shielding the bone matrix during maturation from infiltration of soft tissues cells. This review will focus its attention on the application of electrospinning (ELS) in oral surgery bone regeneration. Despite the abundance of published papers related to the electrospinning technique applied in the field of bone regeneration of the jaws, to the authors' knowledge, no articles report clinical application of these structures. Moreover, only a few records can be found with in vivo application. Therefore, no human studies have to date been detectable. New approaches such as multifunctional multilayering and coupling with bone promoting factors or antimicrobial agents, makes this technology very attractive. However, greater efforts should be made by researchers and companies to turn these results into clinical practice.
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http://dx.doi.org/10.3390/nano10010016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7023267PMC
December 2019

Do Chlorhexidine and Probiotics Solutions Provoke Corrosion of Orthodontic Mini-implants? An In Vitro Study.

Int J Oral Maxillofac Implants 2019 Nov/Dec;33(6):1379-1388

Purpose: The aim of this study was to explore the surface roughness and hardness of the implant head of orthodontic mini-implants made from different alloys before and after their in vitro exposure to agents for prevention of gingivitis, mucositis, and peri-implantitis: chlorhexidine and probiotics.

Materials And Methods: Three types of commercially available mini-implants were tested: 316 stainless steel, titanium Grade 5, and titanium Grade 23 (both Ti-6Al-4V alloys with the same atomic weight percentage of Ti, Al, and V, with the difference being in maximal reduction of O in Grade 23 to 0.13% of atomic weight). They were immersed in three experimental solutions: artificial saliva, saliva with probiotic bacteria Lactobacillus reuteri, and saliva with oral antiseptic chlorhexidine (CHX). Samples were immersed for 28 days, thermocycled, then stored in an incubator at 37°C. Surface roughness and microhardness on five samples of each of the three implant types were measured by atomic force microscopy and the Vickers method, respectively.

Results: Exposure of titanium implant Grade 5 to probiotics significantly increased roughness compared with other media (P < .005). Exposure to CHX significantly increased the roughness of steel implants (P < .05). Neither saliva, probiotic, nor CHX altered microhardness of titanium implants significantly. In steel implants, the exposure to CHX and probiotics decreased microhardness compared with unexposed implants (P < .031), but not in comparison to saliva.

Conclusion: Probiotics seem to increase roughness of titanium mini-implants, while CHX seems to increase roughness of steel mini-implants. Only stainless steel implants had an altered, decreased hardness after exposure to CHX, although the same was found after their exposure to saliva. For patients undergoing orthodontic treatment with temporary anchorage units, CHX could be recommended for titanium, and probiotics for stainless steel mini-implants in oral-hygiene maintenance.
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http://dx.doi.org/10.11607/jomi.7392DOI Listing
December 2019

Cerium Oxide Nanoparticles Absorption through Intact and Damaged Human Skin.

Molecules 2019 Oct 18;24(20). Epub 2019 Oct 18.

Clinical Unit of Occupational Medicine, Department of Medical Sciences, University of Trieste, Via della Pietà 19, 34100 Trieste, Italy.

Cerium oxide (CeO) nanoparticles (NPs) are used in polishing products and absorbents, as promoters in wound healing, and as organopesticide decontaminants. While systemic bioaccumulation and organ toxicity has been described after inhalation, data on CeO NPs' transdermal permeation are lacking. Our study was an in vitro investigation of the permeation of 17-nm CeO NPs dispersed in synthetic sweat (1 g L) using excised human skin on Franz cells. Experiments were performed using intact and needle-abraded skin, separately. The average amount of Ce into intact and damaged skin samples was 3.64 ± 0.15 and 7.07 ± 0.78 µg cm, respectively (mean ± SD, = 0.04). Ce concentration in the receiving solution was 2.0 ± 0.4 and 3.3 ± 0.7 ng cm after 24 h ( = 0.008). The Ce content was higher in dermal layers of damaged skin compared to intact skin (2.93 ± 0.71 µg cm and 0.39 ± 0.16 µg cm, respectively; = 0.004). Our data showed a very low dermal absorption and transdermal permeation of cerium, providing a first indication of Ce skin uptake due to contact with CeO.
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http://dx.doi.org/10.3390/molecules24203759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832931PMC
October 2019

Scanning electron microscopy study of different one-piece foldable acrylic intraocular lenses after injection through microincisional cataract surgery cartridges.

Int Ophthalmol 2020 Feb 17;40(2):369-376. Epub 2019 Oct 17.

Department of Medicine, Surgery and Health Sciences, Eye Clinic, University of Trieste, Piazza Ospedale 1, 34100, Trieste, Italy.

Purpose: To evaluate possible surface alterations of different models of one-piece foldable acrylic intraocular lenses (IOLs) after folding and ejecting process through 2.2-mm microincisional cataract surgery (MICS) cartridges.

Methods: In this experimental laboratory study, the following IOLs were studied: Johnson&Johnson PCB00, HOYA iSert 251, Alcon AcrySof IQ SN60WF, Bausch&Lomb enVISTA MX-60. A total of 80 IOLs were analyzed. Twenty intraocular lenses of each type were studied: ten with a power of + 21 D ± 1 and ten with a power of + 28 D ± 1. IOLs were injected through a dedicated 2.2-mm MICS cartridge into a 50-mL vial containing 10 mL of deionized water. After rinsing and metallization process, scanning electron microscopy images were acquired.

Results: All IOLs presented high-quality construction biomaterials. Some IOLs showed superficial scratches and tears on the optic surface, mainly positioned according to the direction of the stress induced by the folding process. In other cases, small superficial tears were seen in a more peripheral position.

Conclusions: All lenses showed excellent surface quality. After folding and injection process some superficial scratches and tears of the IOL optic were detected in some models. Further studies are needed to assess the possible effects of those superficial damages on the optical quality of the IOLs.
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http://dx.doi.org/10.1007/s10792-019-01193-7DOI Listing
February 2020

Surface properties of commercially available hydrophobic acrylic intraocular lenses: Comparative study.

J Cataract Refract Surg 2019 09 29;45(9):1330-1334. Epub 2019 Jul 29.

Eye Clinic, Department of Medicine, University of Trieste, Italy.

Purpose: To analyze and compare the surface properties of commercially available hydrophobic acrylic intraocular lenses (IOLs).

Setting: Eye Clinic, University of Trieste, Italy.

Design: Experimental study.

Methods: The following 6 single-piece hydrophobic acrylic IOL models with the same dioptric power were studied and compared: Clareon SY60WF, Tecnis PCB00, enVista MX60, CT Lucia 601P, Vivinex iSert XY1, and iSert 251. Topography of the IOL surface was analyzed using atomic force microscopy (AFM). Surface contact angle measurements using the sessile drop method were performed to assess IOL wettability.

Results: The AFM analysis showed that the Vivinex iSert XY1 IOL and Clareon SY60WF IOL had the lowest surface roughness (P < .05); there was no statistically significant difference in surface roughness between the those 2 IOL models (P > .05). Surface contact angle measurements showed that the iSert 251 IOL had the highest hydrophobicity. The CT Lucia 601P IOL had the lowest contact angle of all IOL models.

Conclusions: The AFM analysis and surface contact angle measurements of all IOLs tested showed that the Vivinex iSert XY1 IOL and Clareon SY60WF IOL had the best topographic features. The smoother, more regular surface of these new IOL models might reduce cell adhesion and therefore lower the incidence of posterior capsule opacification.
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http://dx.doi.org/10.1016/j.jcrs.2019.04.011DOI Listing
September 2019

Scanning Electron Microscopy Analysis of the Anterior Capsulotomy Edge: A Comparative Study between Femtosecond Laser-Assisted Capsulotomy and Manual Capsulorhexis.

J Ophthalmol 2018 14;2018:8620150. Epub 2018 Nov 14.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Piazza Ospedale 1, 34129 Trieste, Italy.

Purpose: To compare the capsule edges ultrastructure obtained by two femtosecond laser-assisted cataract surgery (FLACS) platforms and manual continuous curvilinear capsulorhexis (CCC) using scanning electron microscopy (SEM).

Setting: Eye Clinic, University of Trieste, Italy.

Design: Experimental comparative study.

Methods: 150 anterior capsules were collected and divided into three groups as follows: Group 1 (50 capsules) obtained with manual CCC, Groups 2 and 3 (each with 50 capsules) obtained with the Catalys Laser and the LenSx Laser, respectively. All samples were imaged by means of SEM and regularity of the cut surface, and thickness of the capsule edge were evaluated and compared.

Results: All femtosecond laser (FSL) capsules were perfectly circular, whereas some alteration of the circular shape was observed in the manual ones. Group 1 showed a smooth and regular capsule edge without any surface irregularity, conversely Groups 2 and 3 showed postage-stamp perforations on the capsule edge. The cut surface irregularity value in Group 2 was 1.4 ± 0.63, while it was 0.7 ± 0.49 in Group 3 ( < 0.05). Group 1 had a significantly lower thickness of the capsule edge than the FSL groups ( < 0.05). No statistically significant difference in the capsule edge thickness between the FSL groups was found (=0.244).

Conclusions: Despite the presence of slight cut surface irregularities, both FSL capsulotomies showed a better geometry and circularity than the manual ones. Capsulotomy specimens obtained using both FSL capsulotomies showed laser-induced alterations of the capsule edge when compared with smooth and regular edges obtained using manual CCC.
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http://dx.doi.org/10.1155/2018/8620150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261235PMC
November 2018

Three-Dimensional Bone Substitutes for Oral and Maxillofacial Surgery: Biological and Structural Characterization.

J Funct Biomater 2018 Nov 8;9(4). Epub 2018 Nov 8.

Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, I-34125 Trieste, Italy.

Background: Bone substitutes, either from human (autografts and allografts) or animal (xenografts) sources, suffer from inherent drawbacks including limited availability or potential infectivity to name a few. In the last decade, synthetic biomaterials have emerged as a valid alternative for biomedical applications in the field of orthopedic and maxillofacial surgery. In particular, phosphate-based bone substitution materials have exhibited a high biocompatibility due to their chemical similitude with natural hydroxyapatite. Besides the nature of the biomaterial, its porous and interconnected architecture is essential for a correct osseointegration. This performance could be predicted with an extensive characterization of the biomaterial in vitro.

Methods: In this study, we compared the biological, chemical, and structural features of four different commercially available bone substitutes derived from an animal or a synthetic source. To this end, µ-CT and SEM were used to describe the biomaterials structure. Both FTIR and EDS analyses were carried out to provide a chemical characterization. The results obtained by these techniques were correlated with cell adhesion and proliferation of the osteosarcoma MG-63 human cell line cultured in vitro.

Results: The findings reported in this paper indicate a significant influence of both the nature and the structure of the biomaterials in cell adhesion and proliferation, which ultimately could affect the clinical performance of the biomaterials.

Conclusions: The four commercially available bone substitutes investigated in this work significantly differed in terms of structural features, which ultimately influenced in vitro cell proliferation and may so affect the clinical performance of the biomaterials.
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http://dx.doi.org/10.3390/jfb9040062DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6306815PMC
November 2018

Complex Coacervates between a Lactose-Modified Chitosan and Hyaluronic Acid as Radical-Scavenging Drug Carriers.

Biomacromolecules 2018 10 11;19(10):3936-3944. Epub 2018 Sep 11.

Department of Medicine, Surgery and Health Sciences , University of Trieste , Piazza dell'Ospitale 1 , I-34125 Trieste , Italy.

Complex coacervation of two oppositely charged polysaccharides, namely a lactose-modified chitosan (CTL) and hyaluronan (HA), was investigated in this study. Coacervates of the two polysaccharides were prepared by drop-by-drop injection of HA into CTL. Transmittance and dynamic light scattering (DLS) measurements in combination with TEM analyses demonstrated the formation of spheroidal colloids in the nano-/microsize range showing good homogeneity. Strikingly, the presence of 150 mM supporting NaCl did not hamper the colloid formation. Stability studies on selected formulations demonstrated that HA/CTL coacervates were stable up to 3 weeks at 37 °C and behaved as pH-responsive colloids since transition from entangled to disentangled chains was attained for a proper pH range. The possibility of freeze-drying the coacervates for storage purposes and the ability of encapsulating selected payloads were investigated as well, for two values of the fraction of the lactitol side-chain substitution (F). Finally, biological tests using human neutrophils were undertaken at acidic pH value (pH = 6.0): under such experimental conditions, akin to those frequently occurring in the inflammatory microenvironment, coacervates scavenged reactive oxygen species (ROS) generated by these cells in basal conditions. Given the well documented bioactivity of CTL with respect to chitosan toward cartilage regeneration, these findings point to a possible application of HA/CTL-based colloids as scavenging and bioactive carriers for the delivery of therapeutic molecules at confined inflamed sites such as knee joints.
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http://dx.doi.org/10.1021/acs.biomac.8b00863DOI Listing
October 2018

Computed microtomography study of untreated, shaped and filled mesiobuccal canals of maxillary first molars.

Aust Endod J 2019 Apr 16;45(1):72-78. Epub 2018 Aug 16.

Private Practice, Rome, Italy.

This study assessed the effectiveness of modern endodontic shaping and filling procedures on mesiobuccal roots of maxillary molars with two canals. The canals of 20 mesiobuccal roots were treated with Mtwo rotary files, passive ultrasonic irrigation and Guttafusion obturators. X-ray computed microtomography analysis was carried out prior to treatment, after canal shaping and after canal filling to determine the alterations of the canal volume before and after the instrumentation, the volume of the hard tissue debris, and percentage of the volume occupied by filling materials. The shaping instruments and filling materials reached only partially the endodontic space of the second mesiobuccal canal and the accessory endodontic structures. Canal irregularities, ramifications, and interconnections were accumulation sites of hard tissue debris. This study demonstrated that rotary files, passive ultrasonic irrigation and carrier-based filling systems could be partially effective for the treatment of the mesiobuccal canals and their accessory endodontic structures.
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http://dx.doi.org/10.1111/aej.12286DOI Listing
April 2019

Corrosion of Nickel-Titanium Orthodontic Archwires in Saliva and Oral Probiotic Supplements.

Acta Stomatol Croat 2017 Dec;51(4):316-325

Department of Orthodontics, School of Medicine, University of Rijeka, Croatia.

Objectives: The aim of the study was to examine how probiotic supplements affect the corrosion stability of orthodontic archwires made of nickel-titanium alloy (NiTi).

Materials And Methods: NiTi archwires (0.508x0.508 and having the length of 2.5 cm) were tested. The archwires (composition Ni=50.4%, Ti=49.6%) were uncoated, nitrified and rhodium coated. Surface microgeometry was observed by using scanning electron microscope and surface roughness was measured by profilometer through these variables: roughness average, maximum height and maximum roughness depth. Corrosion was examined by electrochemical method of cyclic polarisation.

Results: Rhodium coated alloy in saliva has significantly higher general corrosion in saliva than nitrified alloy and uncoated alloy, with large effect size (p=0.027; η2=0.700). In the presence of probiotics, the result was even more pronounced (p<0.001; η2=0.936). Probiotic supplement increases general and localised corrosion of rhodium coated archwire and slightly decreases general corrosion and increases localised corrosion in uncoated archwire, while in the case of nitrified archwire the probability of corrosion is very low. The differences in surface roughness between NiTi wires before corrosion are not significant. Exposure to saliva decreases roughness average in rhodium coated wire (p=0.015; η2=0.501). Media do not significantly influence surface microgeometry in nitrified and uncoated wires.

Conclusion: Probiotic supplement affects corrosion depending on the type of coating of the NiTi archwire. It increases general corrosion of rhodium coated wire and causes localised corrosion of uncoated and rhodium coated archwire. Probiotic supplement does not have greater influence on surface roughness compared to that of saliva.
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http://dx.doi.org/10.15644/asc51/4/6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5975453PMC
December 2017

On the Correlation between the Microscopic Structure and Properties of Phosphate-Cross-Linked Chitosan Gels.

ACS Appl Mater Interfaces 2018 Apr 23;10(13):10761-10770. Epub 2018 Mar 23.

Department of Medicine, Surgery and Health Sciences , University of Trieste , Piazza dell'Ospitale 1 , I-34125 Trieste , Italy.

Ionic chitosan gels fabricated using multivalent anions, tripolyphosphate (TPP) or pyrophosphate (PPi), respectively, have been investigated as potential biomaterials to be used in tissue engineering. Starting from the hypothesis that the polymer mesh texture at the microscale affects the final performance of the resulting materials, an innovative image analysis approach is presented in the first part of the article, which is aimed at deriving quantitative information from transmission electron microscopy images. The image analysis of the (more extended) central area of the gel networks revealed differences between both the cross-linking densities and pore size distributions of the two systems, the TPP gels showing a higher connectivity. Chitosan-TPP gels showed a limited degradation in simulated physiological media up to 6 weeks, reasonably ascribed to the texture of the (more extended) central area of the gels, whereas PPi counterparts degraded almost immediately. The release profiles and the calculation of diffusion coefficients for bovine serum albumin and cytochrome c, herein used as model payloads, indicated a different release behavior depending on the polymer network homogeneity/inhomogeneity and molecular weight of loaded molecules. This finding was ascribed to the marked inhomogeneity of the PPi gels (at variance with the TPP ones), which had been demonstrated in our previous work. Finally, thorough in vitro studies demonstrated good biocompatibility of both chitosan gels, and because of this feature, they can be used as suitable scaffolds for cellular colonization and metabolic activity.
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http://dx.doi.org/10.1021/acsami.8b01834DOI Listing
April 2018

Release of ICTP and CTX telopeptides from demineralized dentin matrices: Effect of time, mass and surface area.

Dent Mater 2018 03 1;34(3):452-459. Epub 2018 Jan 1.

Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna and IGM-CNR, Unit of Bologna, Italy. Electronic address:

Objective: The present study evaluated the influence of time, mass and surface area of demineralized dentin collagen matrices on telopeptides release. The hypotheses tested were that the rates of ICTP and CTX release by matrix bound endogenous proteases are 1) not time-dependent, 2) unrelated to specimen mass, 3) unrelated to specimen surface area.

Methods: Non-carious human molars (N=24) were collected and randomly assigned to three groups. Dentin slabs with three different thicknesses: 0.37mm, 0.75mm, and 1.50mm were completely demineralized and stored in artificial saliva for one week. Collagen degradation was evaluated by sampling storage media for ICTP and CTX telopeptidases. Activity of MMPs in the aging medium was evaluated using fluorometric activity assay kit.

Results: A statistically significant (p<0.05) decrease in the release of both ICTP and CTX fragments over time was observed irrespective of the specimen thickness. When data were normalized by the specimen mass, no significant differences were observed. Releases of ICTP and CTX were significantly related to the aging time as a function of surface area for the first 12h. Total MMP activity, mainly related to MMP-2 and -9, decreased with time (p<0.05).

Significance: Because the release of collagen fragments was influenced by specimen storage time and surface area, it is likely that cleaved collagen fragments closer to the specimen surface diffuse into the incubation medium; those further away from the exposed surface are still entrapped within the demineralized dentin matrix. Bound MMPs can only degrade the substrate within the limited zone of their molecular mobility.
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http://dx.doi.org/10.1016/j.dental.2017.12.003DOI Listing
March 2018

Chemical and physical analysis of phaco handpiece tip surfaces before and after cataract surgery.

J Cataract Refract Surg 2017 08;43(8):1107-1114

From the Department of Medicine (Cecchini, D'Aloisio, Antonuccio, Turco, Tognetto), Surgery and Health Sciences, University of Trieste, and Istituto Officina dei Materiali del Centro Nazionale delle Ricerche (Bondino, Magnano), Laboratorio di Tecnologie Avanzate, Superfici e Catalisi, Trieste, and the Department of Experimental and Clinical Sciences (Di Nicola), Laboratory of Biostatistics, University G. d'Annunzio Chieti-Pescara, Chieti, Italy; Department of Physics (Magnano), University of Johannesburg, Johannesburg, South Africa.

Purpose: To evaluate the surface chemical composition and roughness of different phaco tips before and after their use during cataract surgery.

Setting: Eye Clinic, University of Trieste, Trieste, Italy.

Design: Experimental study.

Methods: Of the 66 tips studied, 33 (15 new, 15 after single use, and 3 after multiple uses) were studied with X-ray photoemission spectroscopy and 33 (15 new, 15 after single use, and 3 after multiple uses) were examined using scanning electron microscopy with energy dispersive X-ray spectroscopy analysis and contact profilometry. All analyses were performed on the far end of the tip.

Results: Used phaco tips showed signs of wear at the end of the tip, with the deposition of debris. The cutting edge appeared to be rounded and irregular. After surgery, an increase in the surface roughness was detected. The chemical analyses showed modification of the superficial alloy composition and the biological origin of some debris deposited after surgery. The deterioration and wear observed were more remarkable after multiple surgical procedures.

Conclusions: Used phaco tips showed relevant signs of deterioration and deposition of biological material, mostly involving the cutting edge. Reusable tips might release remnants of previous procedures. The adoption of single-use disposable phaco tips seems to be highly advisable.
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http://dx.doi.org/10.1016/j.jcrs.2017.05.027DOI Listing
August 2017

In vivo evaluation of chitosan-glycerol gel scaffolds seeded with stem cells for full-thickness mandibular bone regeneration.

J Oral Sci 2017 ;59(2):225-232

Department of Medical Sciences, University of Trieste.

The aim of this study was to evaluate in vivo bone regeneration, mediated by adipose-derived stem cells (ADSCs), induced to differentiate into osteoblasts and carried by a scaffold gel. In the test group, bone regeneration was mediated by ADSCs, induced to differentiate into osteoblasts, and carried by a scaffold gel. In the control group a scaffold without cells was used. The scaffold, consisting of chitosan and glycerol phosphate, was maintained in situ by a cross-linked resorbable membrane. The osteogenic potential of ADSCs was confirmed by osteocalcin assay and Von Kossa staining performed before implantation. Histological assays detected an initial increase in bone formation in the test group compared with the control group. Microcomputed tomography analysis did not show significant differences between the two groups. Both histological and microcomputed tomography analysis were performed on the ex vivo specimens after a follow-up period of 8 weeks. We observed that differentiated ADSCs could increase bone regeneration and that the scaffold used here can be a suitable carrier to entrap and maintain the cells in situ. On the contrary, the membrane used was not functional in isolating the site of the defect from surrounding soft tissues and caused a significant inflammatory reaction.
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http://dx.doi.org/10.2334/josnusd.16-0235DOI Listing
May 2018

Mechanical and Drug Release Properties of Sponges from Cross-linked Cellulose Nanofibers.

Chempluschem 2017 Jun;82(6):848-858

Department of Chemistry, Materials, and Chemical Engineering "G. Natta", and Local Unit INSTM, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy.

All-organic porous sponges were obtained throughout the direct and solvent-free (oven 105 °C, time>6 h) crosslinking of TEMPO-oxidized cellulose nanofibers (TOCNF) with 25 kDa branched polyethyleneimine (bPEI) in the presence of different amounts of citric acid (CA) as co-crosslinker. The chemical and mechanical stability of these materials was provided by the formation of amide bonds between the carboxylic moieties of TOCNF and CA with the primary amines of bPEI. The mechanical properties were investigated under static and dynamic loads with both dry and wet samples. The materials had the interesting capability to recover their shape with reduced losses in mechanical resistance, while their Young's modulus progressively increased with the content of CA. In work toward developing possible applications of bPEI-TOCNF sponges in drug delivery, amoxicillin (AM) and ibuprofen (IB) were considered as model drugs. All materials showed very good performance in adsorbing both AM and IB (ca. 200 mg g ) from methanol solution. In particular, an increased adsorption of IB was observed in parallel to the increase of citrate moieties in the samples. Moreover, samples crosslinked in presence of CA showed slower kinetic release in aqueous environments than materials obtained without CA.
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http://dx.doi.org/10.1002/cplu.201700185DOI Listing
June 2017

Adhesive coatings based on melanin-like nanoparticles for surgical membranes.

Colloids Surf B Biointerfaces 2017 Jul 29;155:553-559. Epub 2017 Apr 29.

Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy.

Adhesive coatings for implantable biomaterials can be designed to prevent material displacement from the site of implant. In this paper, a strategy based on the use of melanin-like nanoparticles (MNPs) for the development of adhesive coatings for polysaccharidic membranes was devised. MNPs were synthesized in vitro and characterized in terms of dimensions and surface potential, as a function of pH and ionic strength. The in vitro biocompatibility of MNPs was investigated on fibroblast cells, while the antimicrobial properties of MNPs in suspension were evaluated on E. coli and S. aureus cultures. The manufacturing of the adhesive coatings was carried out by spreading MNPs over the surface of polysaccharidic membranes; the adhesive properties of the nano-engineered coating to the target tissue (intestinal serosa) were studied in simulated physiological conditions. Overall, this study opens for novel approaches in the design of naturally inspired nanostructured adhesive systems.
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http://dx.doi.org/10.1016/j.colsurfb.2017.04.057DOI Listing
July 2017

Antibacterial-nanocomposite bone filler based on silver nanoparticles and polysaccharides.

J Tissue Eng Regen Med 2018 02 7;12(2):e747-e759. Epub 2017 May 7.

Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.

Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre-formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast-like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time-stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone-healing process. Copyright © 2016 John Wiley & Sons, Ltd.
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http://dx.doi.org/10.1002/term.2365DOI Listing
February 2018

Scanning Electron Microscopy Evaluation of an EX-PRESS Mini Glaucoma Shunt After Explantation.

J Glaucoma 2017 Jan;26(1):e1-e4

*Eye Clinic †Department of Medical Science, University of Trieste, Trieste, Italy.

We report a case of an explanted stainless steel miniature glaucoma drainage device (EX-PRESS) implanted under a scleral flap for pseudoexfoliation open-angle glaucoma surgical treatment. The glaucoma shunt was implanted in a 75-year-old white man with medically refractive glaucoma. Cataract surgery was performed simultaneously. After 2 years, the shunt extruded through the scleral flap and the conjunctiva and it was, therefore, explanted. Scanning electron microscopy images of the EX-PRESS mini glaucoma shunt were acquired to verify the patency of the device lumen and the presence of fibrosis or cellular adhesion on the device. Energy dispersive spectroscopy for chemical surface characterization of the EX-PRESS shunt was performed. Scanning electron microscopy-acquired images showed minimal extracellular material proliferation on the lumen device. The energy dispersive spectroscopy analysis revealed a high peak of carbon suggesting the organic nature of the residuals found on the shunt lumen. The surface showed few superficial pits, likely due to an initial corrosion process.
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http://dx.doi.org/10.1097/IJG.0000000000000521DOI Listing
January 2017

Micromorphometric analysis of bone blocks harvested with eight different ultrasonic and sonic devices for osseous surgery.

J Craniomaxillofac Surg 2016 Sep 22;44(9):1143-51. Epub 2016 Apr 22.

Department of Medical, Surgical and Health Sciences, University of Trieste, Italy.

Objectives: The aim of this study was to analyse in vitro the main features of osteotomies performed by means of different ultrasonic and sonic systems for bone surgery.

Materials And Methods: Six ultrasonic and two sonic devices for osseous surgery were evaluated during block harvesting on bovine bone. After measuring cutting speed, images of the blocks were acquired by light stereo-microscope and E-SEM, in order to measure the osteotomy thickness and to evaluate the presence of intra-trabecular bone debris and signs of thermal injuries on the bone. Roughness evaluation was performed using a profilometer.

Results: All the ultrasonic instruments required a shorter time than sonic systems to perform the block harvesting (p < 0.05). Piezomed was found to be the most efficient in terms of cutting speed (20.5 mm(2)/min), even if not significantly different from most of the devices here tested (p > 0.05). K-Bisonic and Variosurg 3 showed the smallest percentage variance between tip thickness and osteotomy width. Intra-trabecular debris was found to occur in inverse proportion with the width of the osteotomy: the tighter the track, the higher the amount of debris. Sonicflex Bone, Piezotome 2 and Sonosurgery showed almost no signs of thermal injuries on the osteotomised surfaces.

Conclusions: No single ultrasonic or sonic device combined all the best features of speed, precision and bone micro-architecture preservation.
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http://dx.doi.org/10.1016/j.jcms.2016.04.024DOI Listing
September 2016
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