8 research outputs found

    In-lab characterization of HYPSOS, a novel stereo hyperspectral observing system: first results

    Get PDF
    HYPSOS (HYPerspectral Stereo Observing System, patented) is a novel remote sensing instrument able to extract the spectral information from the two channels of a pushbroom stereo camera; thus it simultaneously provides 4D information, spatial and spectral, of the observed features. HYPSOS has been designed to be a compact instrument, compatible with small satellite applications, to be suitable both for planetary exploration as well for terrestrial environmental monitoring. An instrument with such global capabilities, both in terms of scientific return and needed resources, is optimal for fully characterizing the observed surface of investigation. HYPSOS optical design couples a pair of folding mirrors to a modified three mirror anastigmat telescope for collecting the light beams from the optical paths of the two stereo channels; then, on the telescope focal plane, there is the entrance slit of an imaging spectrograph, which selects and disperses the light from the two stereo channels on a bidimensional detector. With this optical design, the two stereo channels share the large majority of the optical elements: this allowed to realize a very compact instrument, which needs much less resources than an equivalent system composed by a stereo camera and a spectrometer. To check HYPSOS actual performance, we realized an instrument prototype to be operated in a laboratory environment. The laboratory setup is representative of a possible flight configuration: the light diffused by a surface target is collimated on the HYPSOS channel entrance apertures, and the target is moved with respect to the instrument to reproduce the in- flight pushbroom acquisition mode. Here we describe HYPSOS and the ground support equipment used to characterize the instrument, and show the preliminary results of the instrument alignment activities

    Blood wettability of different dental implant surfaces after different pre-treatments: ultrasonic instrumentation, platelet-rich fibrin coating, and acid etching. An in vitro study

    Get PDF
    Background: The blood wettability of titanium implant surfaces favors primary osseointegration and tissue healing in peri-implantitis. The current study aims to evaluate this property on the main different kinds of surfaces, brand new and after treatments. Methods: grade IV titanium disks were used, five machined, five laser-treated, five sandblasted. The experiment was on four steps. Between each step, specimens were sterilized. At the end of each step, a 4 \ub5L blood drop was put on the samples, and contact angles were calculated. The steps consisted of\u20141: no treatment; 2: surface instrumentation with an ultrasonic titanium tip; 3: platelet-rich fibrin (PRF) coating and drying with sterile gauze; 4: etching with phosphoric acid, rinse and saline solution and air-drying. At the end of each phase, a blood drop was placed on the surfaces. Blood for PRF preparation and for calculation of contact angles was collected from a single source. Results: average wettability decreased after instrumentation, and increased after the PRF application to a superior level both to the first and second steps. The highest wettability was obtained after etching. This trend is statistically significant for machined and sandblasted surfaces. Conclusions: In the clinical environment, PRF and phosphoric acid used for conditioning exposed implant surfaces can be used for the healing of peri-implant tissue

    Short-term "in vivo" study on cellular DNA damage induced by acrylic Andresen activator in oral mucosa cells

    No full text
    Objectives: To analyse through comet assay and micronucleus test the viability and DNA damage occurred in buccal mucosa epithelial cells after a short-term exposure to Andresen activator resin monomers. Setting and Sample Population: Test group consisting of 26 subjects was treated with Andresen activator; 16 subjects who had never undergone orthodontic treatment were enrolled in the control group. Material & Methods: Buccal mucosa samples were collected before treatment and after 7, 15, 30, 60 and 90 days. The analyses performed on the cells included the following: cellular viability, comet assay and micronucleus test. Mean \ub1 SD were calculated for cellular viability, tail moment, tail intensity, tail length, micronuclei, binuclear and bud cells. Significance (P < 0.05) was evaluated with Dunnett's test. Results: Cellular viability did not change during observational time, and its trend was similar to the controls. Tail moment and tail intensity significantly increased after 30 and 60 days, respectively, whereas tail length remained unchanged over time in the test group; the same parameters did not change in the control group. In the test group, micronuclei, binuclear and bud cells significantly increased after 30, 60 and 90 days, respectively. Conclusion: The resin monomers of the Andresen activator cause genotoxic effects detectable through comet assay and micronucleus test, but they do not produce clear cytotoxic effects after a 90 days exposure

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

    No full text
    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 (t0) and after (t1) 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 (Ra) 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 t0 and t1. 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

    [Brodie's syndrome. A report of 2 atypical cases].

    No full text
    The aim of the authors is to show the treatment of Brodie's syndrome even in atypical cases where this pathology can not offer typical signs but can be associated to other skeletal deformities of the face. There are two atypical cases of Brodie's syndrome both of them came to our out patient's department. They were grown-up (one 20 one 22 years old), one of them with an extreme vertical expansion of lower third of the face and with a big transverse expansion of the upper maxillary bone, all typical signs of Brodie's syndrome; the other patient was with an extreme transverse expansion of the upper maxilla associated to a II class and a defect of 11, 12, 21, 22. The first patient was treated with orthodontic Tweed technique continued with surgical operation setting out to the contraction of the transverse diameter of the upper maxilla, associated to a Le Fort I osteotomy and an Epker osteotomy of the jaw. This orthodontic-surgical correction, allowed us to achieve a good aesthetic and functional result. The second patient was treated with orthodontics followed by surgical correction of the excessive transverse expansion of the upper maxilla after a Le Fort I osteotomy; a sagittal split of the jaw on Gotte technique was performed to correct the III class. We gave the patient a good aesthetic result with the restoration of the lost teeth in the upper maxilla, reaching in this way a good aesthetic and a well functioning result. We think it's possible to treat patients with atypical Brodie's syndrome with orthodontics or surgery in the same way we treat Brodie's syndrome and other deformities of the face reaching good aesthetic-functional results

    Short and Ultra-Short Implants, in Association with Simultaneous Internal Sinus Lift in the Atrophic Posterior Maxilla: A Five-Year Retrospective Study

    No full text
    : Recent short-term studies suggested the use of short and ultra-short implants in association with a modified osteotome sinus floor elevation (internal sinus lift) technique for the treatment of edentulous resorbed posterior maxilla. The aim of this retrospective study was to investigate this hypothesis in locking-taper implants with a mid-term follow-up of 5 years. Overall, 155 implants (32, 100, and 23 of, respectively, 5.0 mm, 6.0 mm, and 8.0 mm length) were positioned in the atrophic upper maxilla of 79 patients, and 151 implants were loaded with single crowns. Overall implant survival after 5 years was 94.84%. Implant survival for each length group was 93.75%, 94%, and 100% for 5.0, 6.0, and 8.0 mm length, respectively. Preoperative residual crestal bone height of 4.45 (1.3) mm increased to 9.25 (2.13) mm after implant placement and settled at 6.35 (1.73) mm after loading and at 5.25 (1.68) mm at follow-up. Elevation of the Schneiderian membrane was 4.8 (2.46) mm after implant placement, 3.06 (1.3) mm after loading, and 1.46 (1.06) mm at follow-up. Mean variations of periimplant crestal bone loss and first bone-to-implant contact point were, respectively, −0.36 (1.3) mm and −0.62 (1.15) mm. It can be confirmed that internal sinus lift procedure revealed stable bone gain and negligible resorption at mid-term follow-up for atrophic upper crests with reduced height

    Syndromes associated with dental agenesis

    No full text
    INTRODUCTION: Dental agenesis is the congenital absence of a variable number of teeth due to the lack of formation of the corresponding tooth germ. The aim of this work was to investigate the syndromic conditions characterized by dental agenesis. EVIDENCE ACQUISITION: Based on the research conducted through the OMIM \uae (Online Mendelian Inheritance in Man) and PubMed online databases, more than ninety syndromes associated with severe or moderate agenesis have been found. EVIDENCE SYNTHESIS: The main clinical features of these syndromes are described, especially those concerning the stomatognathic apparatus, referring to the most recent literature. Among these syndromes there are three clinical conditions associated with dental agenesis that are common for the clinician: Down Syndrome, ectodermal dysplasia and labio-palatal cleft. CONCLUSIONS: It must be kept in mind that the success of the treatment of these patients is based on the compliance of the patient as well as on the collaboration among specialists
    corecore