2 research outputs found

    Effect of Quality of Dental Restorations and Time Elapsed Since Placement on Biofilm Retention

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    Svrha: U istraživanju se željela procijeniti povezanost zadržavanja biofilma i vremena proteklog otkako je postavljen na smolom restaurirane površine prednjih zuba. Metode: Uzorak se sastojao od 120 zuba 40 pacijenata obaju spolova u dobi između 16 i 60 godina. Ukupno je na njima bilo 230 restauriranih površina. Za mjerenje stupnja zadržavanja biofilma i površinske hrapavosti materijala te vrste kaviteta i rubova bili su potrebni indeks zadržavanja plaka i opseg restauracija (PRRI), a procjenjivala su se i vanjska svojstva preparacije kaviteta. Rezultati: Gotovo sve proučavane površine bile su postavljene prije jedne do pet godina. Najčešći PRRI za zadržavanje biofilma je bio II i IV, 83 posto uzoraka imalo je grubu površinu, a 46,5 posto kavitete II. razreda. subgingivno je bilo 62,2 posto rubova, a kod 38,6 posto zabilježen je višak korištenog restaurativnog materijala. Površinska hrapavost restauracije bila je usko povezana sa zadržavanjem biofilma i vremenom postavljanja (oba p<0,01). Vanjska svojstva restauracije (prekonturiranje, manjak materijala za restauraciju, spoj zub – restauracija) također su značajno bili povezani s vremenom proteklim od postavljanja (svi p<0,05). Zaključak: Vrijeme proteklo od postavljanja smolaste restauracije utječe na hrapavost površine i stupanj zadržavanja biofilma.Objective: The aim of this study was to evaluate associations of biofilm retention on resin-restored surfaces of anterior teeth with quality and time elapsed since placement. Methods: The study sample comprised 120 teeth with 230 restored surfaces in 40 patients of both sexes aged 16–60 years. The Plaque Retention and Extension in Restoration Index (PRRI) was used to measure the degree of biofilm retention, and the surface roughness of the material, cavity type and margins, and external cavity preparation characteristics were also evaluated. Results: Most surfaces analysed had been placed 1–5 years previously. The most prevalent PRRI biofilm retention scores were III and IV, 83.0% of samples presented surface roughness, 46.5% of cavities were class III, 62.2% of surfaces had subgingival margins, and 38.6% retained excessive restorative material. Surface roughness was significantly associated with the degree of biofilm retention and time elapsed since placement (both p < 0.01). Three external cavity preparation characteristics (over-contouring, lack of restorative material, tooth–restoration interface) were also associated significantly with the time elapsed since placement (all p < 0.05). Conclusion: The time elapsed since the placement of resin restorations influences surface roughness and the degree of biofilm retention

    Phylogeny and evolution of life-history strategies in the Sycophaginae non-pollinating fig wasps (Hymenoptera, Chalcidoidea)

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    <p>Abstract</p> <p>Background</p> <p>Non-pollinating Sycophaginae (Hymenoptera, Chalcidoidea) form small communities within <it>Urostigma </it>and <it>Sycomorus </it>fig trees. The species show differences in galling habits and exhibit apterous, winged or dimorphic males. The large gall inducers oviposit early in syconium development and lay few eggs; the small gall inducers lay more eggs soon after pollination; the ostiolar gall-inducers enter the syconium to oviposit and the cleptoparasites oviposit in galls induced by other fig wasps. The systematics of the group remains unclear and only one phylogeny based on limited sampling has been published to date. Here we present an expanded phylogeny for sycophagine fig wasps including about 1.5 times the number of described species. We sequenced mitochondrial and nuclear markers (4.2 kb) on 73 species and 145 individuals and conducted maximum likelihood and Bayesian phylogenetic analyses. We then used this phylogeny to reconstruct the evolution of Sycophaginae life-history strategies and test if the presence of winged males and small brood size may be correlated.</p> <p>Results</p> <p>The resulting trees are well resolved and strongly supported. With the exception of <it>Apocrytophagus</it>, which is paraphyletic with respect to <it>Sycophaga</it>, all genera are monophyletic. The Sycophaginae are divided into three clades: (i) <it>Eukoebelea</it>; (ii) <it>Pseudidarnes</it>, <it>Anidarnes </it>and <it>Conidarnes </it>and (iii) <it>Apocryptophagus</it>, <it>Sycophaga </it>and <it>Idarnes</it>. The ancestral states for galling habits and male morphology remain ambiguous and our reconstructions show that the two traits are evolutionary labile.</p> <p>Conclusions</p> <p>The three main clades could be considered as tribes and we list some morphological characters that define them. The same biologies re-evolved several times independently, which make Sycophaginae an interesting model to test predictions on what factors will canalize the evolution of a particular biology. The ostiolar gall-inducers are the only monophyletic group. In 15 Myr, they evolved several morphological adaptations to enter the syconia that make them strongly divergent from their sister taxa. Sycophaginae appears to be another example where sexual selection on male mating opportunities favored winged males in species with small broods and wingless males in species with large broods. However, some species are exceptional in that they lay few eggs but exhibit apterous males, which we hypothesize could be due to other selective pressures selecting against the re-appearance of winged morphs.</p
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