Search

Author of the study: Nowadays partial or complete ureteral loss following resection or injuries of various etiology is managed with different surgical techniques involving local tissue flaps or autologous tissues interposition. In the last years ureteral tissue engineering using membranes, tubular scaffolds or decellularized matrices has shown promising results for ureteral substitution. The aim of this study is to evaluate the use of antibacterial electrospun polycaprolactone/ rifampicin (PCL/RIF) membranes for the production of ureteral scaffolds with antibacterial properties. Materials and methods: Electrospinning processwas used to produce the membranes that were subsequently impregnated with rifampicin. Membranes stability was evaluated by immersion in Simulated Body Fluid (SBF) at 37 °C. Mechanical properties were evaluated by uniaxial tensile tests, Young’s modulus was calculated for each sample. UV spectrophotometry was used to evaluate in vitro release of rifampicin. The ability of PCL/Rif membranes to sustain cell adhesion and proliferation was evaluated by seeding human urothelial bladder carcinoma cells on the membranes. In order to investigate the antibacterial effect of PCL/Rif membranes, in vitro antibacterial tests were performed using bacterial strains belonging to the “ESKAPE” group. Results: PCL/Rif membranes are characterized by a random distribution of fibers with an average diameter of 0.52 μm.Water contact angle for PCL and PCL/Rif membranes is around 125° and decreases to 0° after air-plasma treatment. When culture medium is used as testing fluid PCL and PCL/Rif contact angles are 116° and 12° respectively. Membranes are deformable up to 300% of their initial dimension and possess an elastic Young modulus of about 20 kPa; after 3 weeks membranes gain the property to sustain a 100% deformation before rupture. The 72% of rifampicin load is released by the membranes in the first 24 hours. Proliferation assay showed a seven-fold increase of cell number adhered on the membranes after 7 days of culture. At the same time in presence of PCL/Rif membranes, rates of bacterial proliferation inhibition ranged from 75 to 94% compared to controls. Conclusions: PCL/Rif membranes represent a promising starting point in the production of ureteral scaffolds with antibacterial properties for ureteral substitution.

Aim: to assess the fracture resistance of maxillary molars restored using lithium disilicate glass-ceramic (LDG) table-top restorations fabricated with two different production protocols. Methods: sixteen maxillary molars were randomly assigned to two groups (n = 8). The teeth received a preparation for a full-coverage table-top restoration with a 90° rounded shoulder margin. Restorations were fabricated using monolithic LDG blocks milled via Cerec 3 CAD/CAM System in group 1 (G1) and heat-pressed LDG in group 2 (G2). All table-tops were luted with Variolink II cement. The specimens were loaded to fracture after thermomechanical aging (1 250 000 cycles). A qualitative analysis on the type of fracture was conducted. Collected data were statistically analyzed with non-parametric test (Mann Whitney U-test). Results: the mean load to fracture was 2395.01 ± 150.96 N in G1 and 1796.58 ± 307.27 N in G2; the difference was statistically significant (p < 0.05). The majority of the specimens showed restorable fractures (6 specimens in G1 and 6 specimens in G2). Conclusion: the milled CAD/CAM LDG table-top restorations withstood higher load before fracturing than the restorations made with the heat-pressed LDG production protocol.

Aim: consequentially to the development of CAD/CAM restorative dental materials, limited data regarding their survival rate and fracture strength is available when they are used as occlusal veneers. The aim of this study is to evaluate the influence of thermomechanical loading on fracture strength of minimally invasive occlusal veneer restorations fabricated from different CAD/CAM materials and bonded to human maxillary molars. Methods: twenty extracted maxillary molars were assigned to two groups (n = 10). LS (zirconia-reinforced lithium silicate) (Celtra Duo, Dentsply Sirona), and PI (polymer-infiltrated ceramic) (Enamic, Vita). The teeth received a preparation for a conservative full-coverage occlusal veneer with a 1-mm cusp reduction with a marginal champfer. Restorations were obtained using the CEREC chair-side (CEREC MC X) and luted with a two-step self-etch adhesive system (Clearfil SE, Kuraray) and a dual resin cement (Variolink II, Ivoclar-Vivadent). After thermomechanical aging (240.000 cycles at 50 N with 5-55°C thermocycling), the specimens were loaded to fracture using a universal testing machine. The statistical analysis was made using one-way ANOVA and Tukey test. Results: all specimens survived the fatigue test. PI showed a higher mean fracture load value (3409 ± 694 N) with statistically significant differences than LS (2352 ± 772 N). Conclusion: PI showed the highest values of fracture resistance followed by LS favoring their use for occlusal veneers.

Aim: the following work assessed the behavior of human Dental Pulp Stem Cells (hDPSC) on PEEK and Titanium samples, in particular their ability to adhere, proliferate and differentiate into osteoblasts. Methods: surface modifications were made to the samples by pre-established protocols of sandblasting and laser micropatterning, to modulate surface roughness. After roughening treatments, samples were divided into two groups: nontreated and treated with air-plasma cleaning process to modulate surface wettability. The hDPSCs were harvested from dental elements and, after expansion in the proper medium, were seeded on the samples to study their behavior. The analyses for the adhesion and the proliferation were performed by Scanning Electron Microscopy and Alamar Blue test, while the differentiation in osteoblasts was evaluated by measuring AlkalinePhosphatase activity. Results: all the samples tested are able to support hDPSCs adhesion, proliferation and differentiation in osteoblasts with differences depending on the material nature and surface. Laser micropatterned titanium samples, in particular, were the best performing in terms of cell differentiation. Air-plasma treatment does not affect cell adhesion and proliferation but improves cell differentiation, in particular on Titanium samples. Conclusion: PEEK and Titanium are confirmed as excellent materials to support the adhesion, the proliferation and the differentiation of the hDPSCs. The biological behavior is strong

Cilj: Ispitati kako uporaba probiotskih preparata utječe na korozijsku stabilnost ortodontskih žičanih lukova nikal-titanijeve legure (NiTi). Materijal i metode: Testirani su NiTi lukovi dimenzija 0,508 × 0,508 mm i duljine 2,5 cm, te (sastav Ni = 50,4 %; Ti = 49,6 %) neobložene, nitrirane i rodirane površine. Površinska mikrogeometrija istraživana je skenirajućim elektronskim mikroskopom pri povećanju od 1000 puta, a površinska hrapavost mjerena je profilometrom te izražena u sljedećim vrijednostima: prosječna hrapavost, maksimalna visina i maksimalna dubina hrapavosti. Vrsta i dinamika korozije ispitani su elektrokemijskom metodom cikličke polarizacije. Rezultati: Legura rodirane površine u slini ima značajno veću opću koroziju od nitirirane i neobložene, uz veliku snagu efekta (p = 0,027; η2 = 0,700). Probiotski preparat povećava opću i lokaliziranu koroziju rodirane žice i malo manjuje opću, te povećava lokaliziranu koroziju neobložene žice, a u slučaju nitrirane žice vrlo je mala mogućnost od pojave korozije. Razlike u površinskoj hrapavosti između nikal-titanijevih žica prije korozije nisu značajne. Izloženost umjetnoj slini smanjuje prosječnu hrapavost rodiranih žica (p = 0,015; η2 = 0,501). Medij ne utječe znatno na površinsku mikrogeometriju nitriranih i neobloženih žica. Zaključak: Probiotski preparat utječe na opću i lokaliziranu koroziju, ovisno o vrsti nikal-titanijeve obloge. Povećava opću koroziju rodirane žice te uzrokuje pojavu lokalizirane korozije neobložene i rodirane žice. Probiotski preparat nema značajan utjecaj na površinsku hrapavost, osim utjecaja same sline., 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: Ni-Ti 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

International audience

A Baited Remote Underwater Video (BRUV) system was used to assess fish assemblages on detritic bottoms (40 m) inside and outside the Capo Gallo - Isola delle Femmine MPA. Our study investigated the suitability of Baited Remote Underwater Video to describe fish (relative) abundance and diversity between sites at different protection levels. The fish assemblages relative abundance and species richness significantly differed between the three different location (A, B e CTL) considered. The largest difference occurred at CTL site position outside the MPA, where 2-fold increase in the number of species was recorded relative to the A and B sites.