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Publisher Copyright: © This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

Purpose The aim of this study was to compare the influence of the number of coronal walls and post-endodontic restorations on the mechanical strength of 165 recently extracted endodontically treated maxillary premolars. Methods The teeth were divided into 3 control (no post) and 3 test groups according to the number of residual walls. Each test group was divided into subgroups according to the type of post-endodontic restoration (single, oval, and multi-post techniques). Samples were prepared conforming to the assigned subgroup. A universal loading machine applied a load parallel to the longitudinal axis of the teeth, thus simulating physiological occlusion. ANOVA and the Kruskal Wallis test were used for comparisons (P ≤ 0.05), and Tukey's test for multiple comparisons. Results For intact teeth, significant differences were found among all 3 subgroups, with single post showing the highest values. For 3 residual walls, oval post resulted in significantly lower values than single and multi-post systems. For 2 residual walls, the multi-post technique showed almost twice the resistance of oval post restorations. Conclusion In oval canals the use of a single or multi-post technique increased post-and-core resistance even in intact teeth, whereas oval fiber posts showed no improvements. Multi-post design improved fracture resistance mostly in maxillary premolars lacking both marginal ridges.

Prunus serotina is one of the worst invasive alien plants throughout Europe, able to rapidly replace autochthonous vegetation and form monospecific stands both in open lands and forested areas. Invasion by shrubs and trees due to abandonment of traditional management practices, is one of the major threats to the conservation of “European dry heaths”, a priority habitat included in the Council Directive 92/43/EEC. The aim of this study was to assess the effects of P. serotina invasion on heathland vegetation in terms of species composition and cover, with special regards to the dominant Calluna vulgaris and Molinia arundinacea, in an area of North-Western Italy subjected to massive invasion by this alien species. We collected data on the plant cover along an invasion gradient in 10 linear transects running from P. serotina invaded stands towards non invaded ones. P. serotina differently affected the heathland vegetation. In particular, the cover of C. vulgaris and other typical heathland species such as Cytisus scoparius sharply decreased at P. serotina cover increasing. On the contrary, positive or no effect of P. serotina cover was found on M. arundinacea. Our results showed that shaded conditions created by the alien tree disfavored light demanding C. vulgaris and C. scoparius, enabling fast grower M. arundinacea to outcompete and replace them. This study emphasizes the urgency to develop management strategies to effectively control P. serotina spread in the area and to restore typical heathland species.

Aim and objective The present study compared the fracture strength and failure pattern of endodontically treated, bi-rooted, maxillary premolars with different number of coronal walls and postendodontic restoration (one vs double post). Materials and methods 105 premolars were divided into 3 groups according to the number of residual walls: control group (intact teeth; n = 15), group 1 (3 residual walls; n = 45), group 2 (2 residual walls; n = 45). Each test group was then divided into 3 subgroups (n = 15 each) according to postendodontic restoration: no post (A), 1 post (B) or 2 posts (C). A load was applied parallel to the longitudinal axis of the teeth, thus simulating physiological occlusion. ANOVA and Tukey's tests were used to detect fracture strength differences among groups, while Chi-square test was used to check differences in fracture pattern. Results No significant differences were observed between control group (intact teeth) and groups A1 (p = 0.999), B1 (p = 0.997) and C1 (p = 1.000); statistically significant differences were detected between control group and groups A2 (p < 0.001), B2 (p < 0.001) and C2 (p < 0.05). Different post placement techniques were non-significantly associated with fracture pattern in both groups 1 (p = 0.666) and 2 (p = 0.143) while, irrespective of the number of posts, the presence of the post was significantly associated with the fracture pattern in teeth with two residual walls. The double-post technique did not further improve the fracture resistance of hardly damaged endodontically treated maxillary bi-rooted premolars compared to single-post technique. Therefore, the insertion of a single post in the palatal canal could be a safer and more conservative choice. Clinical significance The double-post technique did not further improve the fracture resistance of severely structurally compromised endodontically treated maxillary premolars with two roots compared to the single-post technique. Therefore, the safer and less invasive treatment is the placement of a single post in the palatal canal. How to cite this article Spicciarelli V, Marruganti C, Martignoni M, et al. Different Post Placement Strategies for the Restoration of Endodontically Treated Maxillary Premolars with Two Roots: Single Post vs Double Post. J Contemp Dent Pract 2020;21(12):1374–1378.

The aim is to evaluate the influence of remaining tooth substance and post-endodontic restoration on fracture strength of endodontically treated maxillary incisors. 150 maxillary central incisors were divided into three groups, Group 0, intact teeth; Group 1, removal of distal wall; Group 2, removal of mesial and distal walls, and further into two subgroups A0,A1,A2 and B0,B1,B2 according to post-endodontic restoration (post/no-post), then loaded to fracture. Interactions among variables and intergroup significance were tested with two-way ANOVA and Kruskal Wallis's tests (p≤0.05). Tukey's test was applied for multiple comparisons. Statistically significant differences were found between groups B1-A1, and B2-A2, but they were not found between B0-A0. Intragroup analysis showed statistically significant differences in both groups post/no-post with decreasing dental substance. Fiber post placement causes an increase in fracture strength and a reduction of irreparable fractures in endodontically treated maxillary central incisors that lost at least one wall.

In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions. A new combination in the genus Pilosella is proposed. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as Suppl. material 1.

Introduction: The aim of this study was to compare the effect of two different access cavity designs on fracture strength of endodontically treated teeth and on cyclic fatigue resistance of Reciproc blue instruments. Methods: Forty (40) maxillary central incisor teeth and forty (40) upper first premolars were selected and divided into 4 groups (n=20/group): Group 1A, incisors prepared with conservative access cavity (CEC); group 1B, incisors prepared with traditional access cavity (TEC); group 2A, premolars prepared with CEC; group 2B, premolars prepared with TEC. After access cavity preparation, all teeth were endodontically treated, restored and then loaded to fracture. A total of 80 Reciproc blue R25 files were used for root canal shaping and then tested for cyclic fatigue. Normality of data distribution was evaluated by Kolmogorov-Smirnov test. Data were statistically analyzed by Independent T-test and the significance level was set at p

Airport areas have, among flight infrastructures, large green spaces which, not having production purposes, are managed through interventions of minimal disturbance on habitats, with potentially positive effects on the conservation of biodiversity. The checklist of the vascular flora of the airport of Milan Malpensa is here presented. This airport extends for 12.44 km2 in the southwestern portion of the province of Varese (Lombardy, Italy) in the administrative districts of Cardano al Campo, Casorate Sempione, Ferno, Lonate Pozzolo, Samarate, Somma Lombardo and Vizzola Ticino. The collection campaigns were carried out between August 2010 and September 2018. The specimens collected are now kept in the herbarium facility of the Natural History Museum of Milan (MSNM). The floristic list was organized following the arrangement and the nomenclature of the recently published Italian flora checklists. It includes 395 taxa of specific and subspecific rank (9.35% of the entire flora of Lombardy) belonging to 247 genera and 72 families. The native taxa are 318, while the alien ones are 77. The native/aliens ratio is comparable to the one calculated at the regional level (4.10 vs. 4.42). The endemic contingent includes two taxa: Centaurea nigrescens subsp. pinnatifida, Italian endemic, and Euphrasia cisalpina, endemic to the Alps. The Malpensa airport is still the only site confirmed at the national level for Lepidium heterophyllum and, at the regional level, for Festuca muralis and Euphrasia cisalpina. The ecological characteristics and the data analysis will be discussed in a second contribution.

Introduction The purpose of this study was to assess the impact of access cavity preparation and the remaining tooth substance on the fracture strength of endodontically treated teeth. Methods One hundred sound mandibular first and second molar teeth were selected and divided into 1 control and 9 test groups (n = 10/group) as follows: control group, intact teeth; group 1, teeth prepared with traditional endodontic access cavity (TEC); group 2, teeth prepared with conservative endodontic access cavity (CEC); group 3, teeth prepared with truss endodontic access cavity (TREC); group 4, TEC + 3 residual walls; group 5, CEC + 3 residual walls; group 6, TREC + 3 residual walls; group 7, TEC + 2 residual walls; group 8, CEC + 2 residual walls; and group 9, TREC + 2 residual walls. After access cavity preparation, all test teeth were endodontically treated and restored. The specimens were then loaded to fracture in a universal loading machine (Triaxial Tester T400 Digital; Controls srl, Cernusco, Italy), and fracture values were recorded in newtons. The data were analyzed with 2-way analysis of variance and Tukey post hoc analysis for multiple comparisons (P Results Intact teeth were more resistant to fracture than the teeth in all the test groups. No statistically significant differences were found between the 3 tested access cavities (P > .05). Significant differences were observed between the different number of residual walls (P Conclusions TRECs do not increase the fracture strength of endodontically treated teeth in comparison with CECs and TECs. Moreover, the loss of mesial and distal ridges reduced the fracture strength of teeth significantly.

Running at altitude is gaining greater popularity but it may expose participants to the risk of acute mountain sickness (AMS). The study investigated electroencephalographic (EEG) changes and eventual symptoms suggestive of AMS in 5 well-trained lowland native male runners (average age, 38.2 ? 4.6 years; VO2 peak 61.4 ? 2.7 mL?kg–1?min–1 at sea level; best marathon performance at sea level under 3 hours), who completed a marathon at 4300 m altitude. EEG, percentage of peripheral arterial oxygen saturation (% SpaO2) and heart rate (HR) were recorded during wakefulness at rest (supine position) and in comfort: 1) at sea level; 2) at 3600 m after 32 - 38 hours of acute acclimatization; 3) at 4300 m after 145 - 153 hours of chronic acclimatization; and 4) at 4300 m immediately after a marathon race. Symptoms of AMS were evaluated with the Lake Louise questionnaire before any ECG recording. There was a significant decrease in low-voltage high-frequency activities at rest after acute hypoxic-hypobaric exposure at 3600 m as compared to sea level. After six days of acclimatization at 4300 m there was a significant increase in the power of low-voltage high-frequency activities, particularly beta and gamma, indicating an aroused waking state and an integrated activity across widely distributed cortical regions. An increase in the power of low-voltage high-frequency activities over the entire cortex was observed, particularly after completion of the marathon at 4300 m. The increase in the high-frequency activities was probably due to direct and indirect reflex activation of the forebrain and reticular activating system involved in behavioral and metabolic integration of autonomic control and arousal and due to residual activation of the somatomotor and parietal cortex after the end of the marathon. Lake Louise score always resulted lower than 3, indicating no signs of AMS in all the runners. The results of this study indicate that in well-trained and acclimatized athletes, arousal has a protective role in preventing excessive oxygen deprivation also after an endurance exercise performed at high altitude. The absence of AMS fond in our study bear out that well trained and acclimatized runners, can safely participate in a marathon at high altitude that gives rise to temporary EEG changes without inducing paroxysmal phenomena.

This paper analyses the mechanical behaviour of a new reinforced anatomical post-systems (RAPS) for endodontic restoration. The composite restorative material (CRM) completely fills the root canal (as do the commonly used cast metal posts) and multiple prefabricated composite posts (PCPs) are employed as reinforcements. Numerical simulations based on 3D linearly elastic finite element models under parafunctional loads were performed in order to investigate the influence of the stiffness of the CRM and of the number of PCPs. Periodontal ligament effects were taken into account using a discretised anisotropic nonlinearly elastic spring system, and the full discrete model was validated by comparing the resulting stress fields with those obtained with conventional restorations (cast gold-alloy post, homogeneous anatomical post and cemented single PCP) and with the natural tooth. Analysis of the results shows that stresses at the cervical/middle region decrease as CRM stiffness increases and, for large and irregular root cavities that apical stress peaks disappear when multiple PCPs are used. Accordingly, from a mechanical point of view, an optimal RAPS will use multiple PCPs when CRM stiffness is equal to or at most twice that of the dentin. This restorative solution minimises stress differences with respect to the natural tooth, mechanical inhomogeneities, stress concentrations on healthy tissues, volumes subject to shrinkage phenomena, fatigue effects and risks of both root fracture and adhesive/cohesive interfacial failure.