This study evaluated the influence of curing tip distance, shade and filler particle size on Vickers microhardness (VHN) of composite resins. Two composites were tested: Filtek Z250 microhybrid (3M ESPE; shades A1 and A3.5) and Filtek Supreme nanofilled (3M ESPE; shades A1B and A3.5B). For each resin, 42 specimens (5 mm in diameter and 2 mm height) were prepared being 21 for each shade. The specimens were exposed using a 20-second exposure to a quartz-tungsten-halogen light source with an irradiance of approximately 560 mW/cm2, at the following distances: 0 mm (surface contact), 6 mm and 12 mm from composite surface. Effectiveness of cure of different resins, shades and curing distances was determined by measuring the top and bottom hardness (VHN) of specimens using a digital microhardness tester (load: 50 g; dwell time: 45 seconds) 24 hours following curing. The hardness ratio was calculated by dividing VHN of the bottom surface by VHN of top surface. Three-way ANOVA and Tukey's post-hoc test (p<0.05) revealed statistically significant differences for all analyzed factors. As for top hardness, as microhardness ratio (bottom/top), the factors shade, distance and composite filler particle size exerted influence on resin curing. Lighter shade composites (A1 and A1B) showed higher hardness values. At 6 and 12 mm curing tip distances, hardness was lower when compared to 0 mm. The microhybrid composite resin presented higheer hardness, being its microhardness ratio satisfactory only at 0 mm for both shades and at 6 mm for the lighter shade. The nanofilled composite resin did not present satisfactory microhardness at the bottom while the microhybrid composite resin had higher hardness than the nanofilled. Composite's curing tip distance and shade can influence hardness.
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This research analyzed the influence of bur and erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser caries removal on cavity characteristics and marginal seal of composite resin restorations. One hundred and forty human dental root samples were used. After in vitro root caries induction using Streptococcus mutans, the carious lesions were removed either by a conventional technique using burs (G1=control) or by using an Er,Cr:YSGG laser (λ=2.78 μm, 20 Hz, pulse duration is approximately equal to 140 μs, noncontact mode using a 600-μm tip) with the following power outputs: G2: 1.0 W; G3: 1.25 W; G4: 1.5 W; G5: 1.75 W; G6: 2.0 W; G7: 2.25 W; G8: 2.5 W; G9: 2.75 W; G10: 3.0 W; G11: 3.25 W; G12: 3.5 W; G13: 3.75 W; and G14: 4.0 W. Samples in the 14 groups (n=10) were conditioned with Clearfil SE Bond and restored with a flowable composite. They were then thermocycled (1000 cycles) and immersed into a 2% methylene blue solution for microleakage analysis. The data were statistically compared (analysis of variance or Spearman correlation tests; p≤0.05). The lased groups showed significantly greater microleakage indexes, cavity depths, and presence of residual caries than did those of the control group. There was a strong positive correlation between residual caries and microleakage. The results indicate that Er,Cr:YSGG laser irradiation is not a good alternative to the use of burs for root caries removal since it may cause a significant loss of marginal sealing in composite resin restorations.
Purpose Too often people with complex mental health needs do not find their way out of the mental health system or find satisfactory solutions that enable them to live a full life. In 2015 the Mental Health Department (MHD) of Trieste established the Recovery House pilot project to address this concern. The paper aims to Investigate the project. Design/methodology/approach The Recovery House was co-created with and for people between 18 and 35 years old with diagnoses of psychosis and other complex mental health conditions. An integral part of the pilot was the organization of the “Recovery Community,” inspired by the Assembly model embraced by Franco Basaglia. The Recovery Community met regularly to both support and learn from the Recovery House and aimed to create a democratic and reflective space where power relationships, self-determination, responsibility and ownership by all the stakeholders, including family members, could be explored together. Findings Over a period of 31 months, four groups of people have successfully completed their residency at the Recovery House. In total, 89 percent of people who stayed at the Recovery House did so up to six months. After the period of staying at the Recovery House most of them moved to independent living or shared supported accommodation. Originality/value This initiative sheds light on the fact that democratic values, approaches and structures can improve both service functioning and the recovery outcomes for people with complex health needs. Further, the Recovery House has had a significant effect on the culture and practice of the MHD in adopting a comprehensive approach to emotional distress.
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