Publications by authors named "Orlando Donfrancesco"

9 Publications

  • Page 1 of 1

Angle of Insertion and Torsional Resistance of Nickel-Titanium Rotary Instruments.

Materials (Basel) 2021 Jul 4;14(13). Epub 2021 Jul 4.

Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, 00161 Rome, Italy.

Previously published studies have investigated the influence of instrument access on cyclic fatigue resistance. However, no studies have evaluated the relationship between angulated access and torsional resistance. The aim of this study was to investigate the influence of the angle of access on the torsional resistance of endodontic instruments. One hundred and eighty instruments were selected: 90 F-One Blue 25/04 and 90 HeroShaper 25/04 instruments. Three subgroups ( = 30) for each instrument type (A and B) were established according to the angle of insertion of the instruments inside the artificial canal (0°, 10° and 20°). The tests were performed using a custom-made device consisting of the following: a motor that can record torque values of 0.1 s; interchangeable stainless-steel canals with different curvature (0°, 10° and 20°) that allow the instrument's angulated insertion and keep it flexed during testing procedures; and a vise used to secure the instrument at 3 mm from the tip. Torque limit was set to 5.5 Ncm, and each instrument was rotated at 500 rpm until fracture occurred. Torque to fracture (TtF) was registered by the endodontic motor, and the fragment length (FL) was measured with a digital caliper. Fractographic analysis was performed using a scanning electron microscopy (SEM) evaluation to confirm the cause of failure. TtF values and fragment length (FL) values were statistically analyzed using one-way analysis of variance (ANOVA) test and the Bonferroni correction for multiple comparisons across the groups with significance set to a 95% confidence level. Regarding the F-One Blue instruments, the results showed a higher TtF for group A3 (20°) than for group A1 (0°) and group A2 (10°), with a statistically significant difference between group A3 and the other two groups ( < 0.05), whereas no statistically significant difference was found between group A1 and group A2 ( > 0.05). Regarding the HeroShaper instrument, the results showed the highest TtF for group B3, with a statistically significant difference between the three subgroups B1, B2 and B3 ( < 0.05). The results showed that the torsional resistance increases as the angle of instrument access increases with a varying intensity, according to the crystallographic phase of the instrument selected.
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http://dx.doi.org/10.3390/ma14133744DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8269838PMC
July 2021

Nickel-Titanium Rotary Instruments: An Comparison (Torsional Resistance of Two Heat-treated Reciprocating Files).

J Contemp Dent Pract 2021 Apr 1;22(4):361-364. Epub 2021 Apr 1.

Department of Oral and Maxillo-facial Sciences, Sapienza University of Rome, Rome, Italy.

Aim And Objective: The present study aims to evaluate the difference in torsional resistance of two reciprocating nickel-titanium (Ni-Ti) rotary files: WaveOne Gold and EdgeOne Fire.

Materials And Methods: A total of 40 nickel-titanium rotary instruments ( = 40): 20 WaveOne Gold Small (WOGS) and 20 EdgeOne Fire Small (EOFS) were divided into two groups. Each instrument was tested using a torsional resistance device already validated in previous studies to evaluate and compare torsional resistance. The static torsional test was implemented by blocking each instrument at 3 mm from the tip and rotating it until fracture with a reciprocating motion. Torque to fracture (TtF) and fragment length (FL) were measured and statistically analyzed.

Results: Statistical analysis of TtF found significant differences between the two groups (<0.05). The EOFS showed higher TtF if compared to WOGS, with a mean value and a standard deviation of 3.05 ± 0.07 (N cm) against 2.97 ± 0.08 (N cm). Data for FL showed no significant differences (>0.05) between the two groups.

Conclusion: According to the results of this study, it is reasonable to assert that EOFS instruments showed a higher torsional resistance if compared to the WOGS.

Clinical Significance: As evidenced by this study, EOFS should be considered as a safer solution, in terms of torsional resistance, if compared to WOGS, reducing the risk of intracanal separation due to excessive torsional load.
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April 2021

Biocompatibility and Antibiofilm Properties of Calcium Silicate-Based Cements: An In Vitro Evaluation and Report of Two Clinical Cases.

Biology (Basel) 2021 May 26;10(6). Epub 2021 May 26.

Department of Oral and Maxillofacial Science, Sapienza University of Rome, Via Caserta 6, 00161 Rome, Italy.

Calcium silicate-based cements have reached excellent levels of performance in endodontics, providing predictable and successful results. To better assess the properties of these bioactive materials, the present study aimed to compare the biocompatibility and antibiofilm properties of ProRoot MTA and Biodentine. Human osteogenic sarcoma (Saos-2) cells were cultured on ProRoot MTA and Biodentine samples or in the presence of both cement extracts. Cell viability assay, measurement of reactive oxygen species (ROS), immunofluorescence analysis, as well as morphological evaluations were conducted. Moreover, was used to assess the biofilm forming ability on ProRoot MTA and Biodentine disks. Finally, both cements were applied in vivo to treat immature permanent teeth affected by reversible pulpitis. Results: Cell viability assay demonstrated that Saos-2 cells had a dose- and time-dependent cytotoxicity to both analyzed cements, although cells exposed to ProRoot MTA showed a better cell vitality than those exposed to Biodentine ( < 0.001). Both cements demonstrated ROS production while this was greater in the case of Biodentine than ProRoot MTA ( < 0.001). Immunofluorescence images of the cytoskeleton and focal adhesions showed no differences in Saos-2 cells grown in the presence of ProRoot MTA eluate; whereas in the Biodentine groups, cells showed a morphology and focal adhesions more similar to that of the control sample, as the eluate concentration decreased. Morphological analysis revealed that Saos-2 cells were more flattened and exhibited better spreading when attached to ProRoot MTA disks than to Biodentine ones. The antibiofilm properties showed a time-dependent powerful inhibition of superficial colonization and an antibiofilm effect of both cements. Clinically, complete root formation of the treated elements was achieved using the two studied cements, showing stable results over time. ProRoot MTA and Biodentine was demonstrated to be biocompatible and to possess antibiofilm properties. Their clinical application in vital pulp therapy provided successful outcomes after 2 years of follow-up.
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http://dx.doi.org/10.3390/biology10060470DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8226987PMC
May 2021

Microscopy Methods for Biofilm Imaging: Focus on SEM and VP-SEM Pros and Cons.

Biology (Basel) 2021 Jan 12;10(1). Epub 2021 Jan 12.

Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.

Several imaging methodologies have been used in biofilm studies, contributing to deepening the knowledge on their structure. This review illustrates the most widely used microscopy techniques in biofilm investigations, focusing on traditional and innovative scanning electron microscopy techniques such as scanning electron microscopy (SEM), variable pressure SEM (VP-SEM), environmental SEM (ESEM), and the more recent ambiental SEM (ASEM), ending with the cutting edge Cryo-SEM and focused ion beam SEM (FIB SEM), highlighting the pros and cons of several methods with particular emphasis on conventional SEM and VP-SEM. As each technique has its own advantages and disadvantages, the choice of the most appropriate method must be done carefully, based on the specific aim of the study. The evaluation of the drug effects on biofilm requires imaging methods that show the most detailed ultrastructural features of the biofilm. In this kind of research, the use of scanning electron microscopy with customized protocols such as osmium tetroxide (OsO), ruthenium red (RR), tannic acid (TA) staining, and ionic liquid (IL) treatment is unrivalled for its image quality, magnification, resolution, minimal sample loss, and actual sample structure preservation. The combined use of innovative SEM protocols and 3-D image analysis software will allow for quantitative data from SEM images to be extracted; in this way, data from images of samples that have undergone different antibiofilm treatments can be compared.
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http://dx.doi.org/10.3390/biology10010051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7828176PMC
January 2021

Essential Oils Biofilm Modulation Activity, Chemical and Machine Learning Analysis. Application on Isolates from Cystic Fibrosis Patients.

Int J Mol Sci 2020 Dec 4;21(23). Epub 2020 Dec 4.

Department of Drug Chemistry and Technology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy.

Bacterial biofilm plays a pivotal role in chronic () infection and its inhibition may represent an important strategy to develop novel therapeutic agents. The scientific community is continuously searching for natural and "green alternatives" to chemotherapeutic drugs, including essential oils (EOs), assuming the latter not able to select resistant strains, likely due to their multicomponent nature and, hence, multitarget action. Here it is reported the biofilm production modulation exerted by 61 EOs, also investigated for their antibacterial activity on strains, including reference and cystic fibrosis patients' isolated strains. The EOs biofilm modulation was assessed by Christensen method on five strains. Chemical composition, investigated by GC/MS analysis, of the tested EOs allowed a correlation between biofilm modulation potency and putative active components by means of machine learning algorithms application. Some EOs inhibited biofilm growth at 1.00% concentration, although lower concentrations revealed different biological profile. Experimental data led to select antibiofilm EOs based on their ability to inhibit biofilm growth, which were characterized for their ability to alter the biofilm organization by means of SEM studies.
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http://dx.doi.org/10.3390/ijms21239258DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7730550PMC
December 2020

The effect of low and ultra-low oxygen tensions on mammalian embryo culture and development in experimental and clinical IVF.

Syst Biol Reprod Med 2020 Aug 7;66(4):229-235. Epub 2020 May 7.

Department of Life, Health and Environmental Sciences, University of L'Aquila , L'Aquila, Italy.

Over the last forty years, many trials have been performed using mammalian embryo cultures with reduced oxygen tension (O) to encourage proper embryo development and increase the success rate for fertilization (IVF) outcome. Even if the use of atmospheric O (20%) affects embryo development and intracellular redox balance, the use of low (5% O, physiologic) and ultra-low (close or less to 5% O) O applied to embryo culture is still under debate. Numerous studies in various mammalian species have shown that embryo development improves when culturing embryos under low O, although culture conditions are not the only factors involved in the success of IVF. This article reviews the literature data of the last four decades and discusses the current evidence on the use of low and ultra-low O in embryo culture, and examines the impact of multiple factors on IVF outcomes.

Abbreviations: O: oxygen tension; IVF: fertilization; IVC: culture; ET: embryo transfer; ROS: reactive oxygen species; ARTs: assisted reproductive technologies.
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http://dx.doi.org/10.1080/19396368.2020.1754961DOI Listing
August 2020

SEM BSE 3D Image Analysis of Human Incus Bone Affected by Cholesteatoma Ascribes to Osteoclasts the Bone Erosion and VpSEM dEDX Analysis Reveals New Bone Formation.

Scanning 2020 15;2020:9371516. Epub 2020 Feb 15.

Department SAIMLAL Section of Human Anatomy, Laboratory of Electron Microscopy "Pietro M. Motta", Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy.

Bone erosion is considered a typical characteristic of advanced or complicated cholesteatoma (CHO), although it is still a matter of debate if bone erosion is due to osteoclast action, being the specific literature controversial. The purpose of this study was to apply a novel scanning characterization approach, the BSE 3D image analysis, to study the pathological erosion on the surface of human incus bone involved by CHO, in order to definitely assess the eventual osteoclastic resorptive action. To do this, a comparison of BSE 3D image of resorption lacunae (resorption pits) from osteoporotic human femur neck (indubitably of osteoclastic origin) with that of the incus was performed. Surface parameters (area, mean depth, and volume) were calculated by the software Hitachi MountainsMap© from BSE 3D-reconstructed images; results were then statistically analyzed by SPSS statistical software. Our findings showed that no significant differences exist between the two groups. This quantitative approach implements the morphological characterization, allowing us to state that surface erosion of the incus is due to osteoclast action. Moreover, our observation and processing image workflow are the first in the literature showing the presence not only of bone erosion but also of matrix vesicles releasing their content on collagen bundles and self-immuring osteocytes, all markers of new bone formation on incus bone surface. On the basis of recent literature, it has been hypothesized that inflammatory environment induced by CHO may trigger the osteoclast activity, eliciting bone erosion. The observed new bone formation probably takes place at a slower rate in respect to the normal bone turnover, and the process is uncoupled (as recently demonstrated for several inflammatory diseases that promote bone loss) thus resulting in an overall bone loss. Novel scanning characterization approaches used in this study allowed for the first time the 3D imaging of incus bone erosion and its quantitative measurement, opening a new era of quantitative SEM morphology.
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http://dx.doi.org/10.1155/2020/9371516DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7048945PMC
February 2020

Differences in cyclic fatigue lifespan between two different heat treated NiTi endodontic rotary instruments: WaveOne Gold vs EdgeOne Fire.

J Clin Exp Dent 2019 Jul 1;11(7):e609-e613. Epub 2019 Jul 1.

Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Italy.

Background: Aim of this study is to investigate the cyclic fatigue resistance of the Gold treated WaveOne Gold and the Firewire treated EdgeOne Fire instruments. The null hypotesis was that there were no differences between the lifespan of Gold treated and FireWire treated instruments when subjected to cyclic fatigue tests.

Material And Methods: 40 new NiTi instruments with a length of 25 mm were tested: 20 Wave One Gold Medium (WOG), tip size 35 and variable taper (Dentsply Maillefer, Ballaigues, Switzerland) and 20 Edge One Fire (EOF) (EdgeEndo, Albuquerque, New Mexico) tip size 35 and the same variable taper. A mobile support for the electric handpiece and a stainless-steel block containing the artificial canals were used. The same artificial root canal with a 90 degrees angle of curvature and 2 mm radius of curvature was used for all the tested instruments and the WOG counter-clock wise reciprocating motion with an engaging angle of 150° and a disengaging angle of 30° at 300 rpm, was selected for the test. All instruments were inserted at the same length (18mm) and then rotated in the same reciprocating motion until fracture occurred: the time was stopped as soon as the fracture was visible and video-recorded with a 1/100 sec chronometer. Differences among groups were statistically evaluated with an analysis of variance test ANOVA (significance level was set at <0.05).

Results: Mean values of time to fracture (TtF) for EOF instruments were 28,00 seconds (SD +/- 2,64) and for WOG instruments were 14,67 seconds (SD +/- 2,41). Statistical analysis found significant differences between the TtF of the two instruments (<0,05).

Conclusions: Firewire instruments resulted to be about two times more resistant to cyclic fatigue when compared with identical instruments made with Gold treatment. Endodontics, NiTi, Waveone Gold, EdgeOne Fire, Cyclic Fatigue.
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http://dx.doi.org/10.4317/jced.55839DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6731004PMC
July 2019

Role of the Flat-Designed Surface in Improving the Cyclic Fatigue Resistance of Endodontic NiTi Rotary Instruments.

Materials (Basel) 2019 Aug 8;12(16). Epub 2019 Aug 8.

Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, 00161 Rome, Italy.

The aim of this study was to investigate the role of the flat-designed surface in improving the resistance to cyclic fatigue by comparing heat-treated F-One (Fanta Dental, Shanghai, China) nickel-titanium (NiTi) rotary instruments and similar prototypes, differing only by the absence of the flat side. The null hypothesis was that there were no differences between the two tested instruments in terms of cyclic fatigue lifespan. A total of 40 new NiTi instruments (20 F-One and 20 prototypes) were tested in the present study. The instruments were rotated with the same speed (500 rpm) and torque (2 N) using an endodontic motor (Elements Motor, Kerr, Orange, CA, USA) in the same stainless steel, artificial canal (90° angle of curvature and 5 mm radius). A Wilcoxon-Mann-Whitney test was performed to assess the differences in terms of time to fracture and the length of the fractured segment between the flat- and non-flat-sided instruments. Significance was set at = 0.05. The differences in terms of time to fracture between non-flat and flat were statistically significant ( < 0.001). In addition, the differences in terms of fractured segment length were statistically significant ( = 0.034). The results of this study highlight the importance of flat-sided design in increasing the cyclic fatigue lifespan of NiTi rotary instruments.
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http://dx.doi.org/10.3390/ma12162523DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6720207PMC
August 2019
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