Clinical Classification of Bone Augmentation Procedure Failures in the Atrophic Anterior Maxillae: Esthetic Consequences and Treatment Options

Although the number of complications and failures in bone augmentation procedures is still relatively high, these problems remain poorly documented. Moreover, the literature concerning reconstructive techniques and the treatment of their complications in the anterior areas rarely considers the final esthetic result. The aim of this paper is to propose a new classification of bone augmentation complications in the esthetic area, providing treatment guidelines useful for the management of these cases. Failures of bony regeneration procedures can be mainly divided into partial failures and complete failures. A partial failure can be solved with a corrective surgical intervention: this second surgery can have success or may not be able to provide the desired esthetic result. When the bone reconstructive procedure fails totally, a complete failure occurs and the whole procedure has to be repeated. This new intervention can have success but also this new reconstructive surgery can fail in the same way as the first, causing important damage and a compromise solution that will hardly be acceptable from an esthetic point of view. Bone augmentation techniques are not completely predictable and are not always able to guarantee the expected result, especially in the atrophic anterior maxilla. Complications and failures can often occur and this possibility must always be clearly explained to those patients with high esthetic demands and expectations

Prevalence and treatment of retrograde peri-implantitis: a retrospective cohort study covering a 20-year period

Objectives: The aims of this retrospective study were to report data on the prevalence of retrograde peri-implantitis (RPI) in a single-center in a 20-year observation period and to evaluate implant survival after surgical treatment. Materials and methods: A retrospective cohort study was conducted screening all patients who underwent implant treatment in a private practice. Patients were enrolled if they had one or more implants showing a radiolucency around the implant apex, without implant mobility. Furthermore, clinical symptoms of RPI and days from symptoms’ appearance after implant placement were also collected, as well as periodontal and endodontic status of nearby teeth. All patients were treated with the same surgical approach: antibiotic therapy, mechanical curettage, chemical decontamination and xenograft application. Results: Out of the 1749 implants placed, only 6 implants were classified as affected by RPI, with a prevalence of 0.34%. Clinical symptoms of RPI (pain, swelling, dull percussion or fistula presence) varied among patients and were reported after a mean period of 51.83 ± 52.43 days. Conclusions: RPI was successfully treated with surgical curettage and bone substitute application and all implants are still in place after a mean follow-up of 8.83 ± 5.34 years. Clinical relevance: Bacteria from teeth with failed endodontic treatment or residual lesions might be reactivated by drilling for implant osteotomy, with subsequent colonization of the implant apex and possible failure before prosthetic loading. Therefore, it might be recommended to take a periapical x-ray at implant placement and after 6–8 weeks in order to intercept RPI before prostheses delivery

comspat: an R package to analyze within-community spatial organization using species combinations

The diversity of species combinations observable in sampling units reflects a species' uneven distribution and preference for specific abiotic and biotic conditions – a phenomenon most commonly expressed in terms of ecological assembly rules of plant communities and other sessile organisms (e.g. subtidal algae, invertebrates and coral reefs). We present comspat, a new R package that uses grid or transect data sets to measure the number of realized (observed) species combinations (NRC) and the Shannon diversity of realized species combinations (compositional diversity; CD) as a function of spatial scale. NRC and CD represent two measures from a model family developed by Pál Juhász-Nagy based on information theory. Classical Shannon diversity measures biodiversity based on the number and relative abundance of species, whereas the specific version of Shannon diversity presented here characterizes biodiversity and provides information on species coexistence relationships; both measures operate at fine-scale within the sampling unit or within the community. comspat offers two commonly applied null models, complete spatial randomness and random shift, to disentangle the textural, intraspecific and interspecific effects on the observed spatial patterns. Combined, these models assist users in detecting and interpreting spatial associations and inferring assembly mechanisms. Our open-sourced package provides a vignette that describes the method and reproduces the figures from this paper to help users contextualize and apply functions to their data

Electrochemical faceting of metal electrodes

Electrochemical faceting is a term recently coined to denote the preferred crystallographic orientation of grains in polycrystalline metals developed when they are subjected to periodic potential perturbations of determined characteristics. Electrochemical faceting can also be applied to small single crystal beads resulting from melting polycrystalline metal wires. By properly adjusting the conditions defining the periodic perturbation, the resulting electrode surface acquires different preferred orientations which, depending on the nature of the electrode metal, can be followed either electrochemically through conventional voltammetry in the H and O electroadsorption/electrodesorption potential range, and in upd of different metals, or by scanning electron microscopy. The procedure has already been successfully applied to platinum, gold, rhodium and palladium. Electrochemical faceting involves at least two stages, namely, the initiation stage related to an electroadsorption process and a propagation stage associated with the electrodissolution and electrodeposition of the base metal in the acid electrolyte. Stabilization procedures for the freshly oriented surfaces and roughness development are also considered.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta

A proposed protocol for ordinary and extraordinary hygienic maintenance in different implant prosthetic scenarios

Prevention of peri-implantitis involves the early diagnosis of peri-implant mucositis. This article presents a protocol of hygienic maintenance in different implant prosthetic scenarios: single crown, fixed partial prosthesis, fixed full-arch, and overdentures. Others clinical conditions have to be taken into consideration: patient compliance; history of periodontitis; implants placed in augmented bone; short, zygomatic, pterygoid, and tilted implants; and complex prosthesis with false gingiva. Two levels of implant maintenance are described: ordinary, performed by dental hygienist, and extraordinary, carried out by both dentist and hygienist. Extraordinary maintenance also involves the removal and decontamination of the prosthetic structure. To obtain an effective prevention of peri-implantitis, one must plan ordinary and extraordinary hygiene in relation to the type of rehabilitation and clinical parameters

Electrochemical faceting of metal electrodes

Electrochemical faceting is a term recently coined to denote the preferred crystallographic orientation of grains in polycrystalline metals developed when they are subjected to periodic potential perturbations of determined characteristics. Electrochemical faceting can also be applied to small single crystal beads resulting from melting polycrystalline metal wires. By properly adjusting the conditions defining the periodic perturbation, the resulting electrode surface acquires different preferred orientations which, depending on the nature of the electrode metal, can be followed either electrochemically through conventional voltammetry in the H and O electroadsorption/electrodesorption potential range, and in upd of different metals, or by scanning electron microscopy. The procedure has already been successfully applied to platinum, gold, rhodium and palladium. Electrochemical faceting involves at least two stages, namely, the initiation stage related to an electroadsorption process and a propagation stage associated with the electrodissolution and electrodeposition of the base metal in the acid electrolyte. Stabilization procedures for the freshly oriented surfaces and roughness development are also considered.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta

Effect of different implant placement depths on crestal bone levels and soft tissue behavior: A 5â year randomized clinical trial

ObjectivesThis randomized clinical trial analyzed the longâ term (5â year) crestal bone changes and soft tissue dimensions surrounding implants with an internal tapered connection placed in the anterior mandibular region at different depths (equiâ and subcrestal).Materials and methodsEleven edentulous patients were randomly divided in a splitâ mouth design: 28 equicrestal implants (G1) and 27 subcrestal (1â 3 mm) implants (G2). Five implants were placed per patient. All implants were immediately loaded. Standardized intraoral radiographs were used to evaluate crestal bone (CB) changes. Patients were assessed immediately, 4, 8, and 60 months after implant placement. The correlation between vertical mucosal thickness (VMT) and soft tissue recession was analyzed. Subâ group analysis was also performed to evaluate the correlation between VMT and CB loss. Rankâ based ANOVA was used for comparison between groups (α = .05).ResultsFiftyâ five implants (G1 = 28 and G2 = 27) were assessed. Implant and prosthetic survival rate were 100%. Subcrestal positioning resulted in less CB loss (â 0.80 mm) when compared to equicrestal position (â 0.99 mm), although the difference was not statistically significant (p > .05). Significant CB loss was found within the G1 and G2 groups at two different measurement times (T4 and T60) (p  .05).ConclusionsThere was no statistically significant difference in CB changes between subcrestal and equicrestal implant positioning; however, subcrestal position resulted in higher bone levels. Neither mucosal recession nor vertical mucosa thickness was influenced by different implant placement depths.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154286/1/clr13569.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154286/2/clr13569_am.pd

The Italian endemic forest plants: an annotated inventory and synthesis of knowledge

Background and aims – Forests are among the most threatened ecosystems worldwide, and endemic plants are often a vulnerable component of the flora of a given territory. So far, however, understory forest endemics of southern Europe have received little attention and are poorly known for several aspects. Material and methods – We developed the first list of native vascular plants that are restricted to Italian forests. Available information on taxonomy, regional distribution, ecology, biology, functional traits, and conservation status was collected for each taxon, allowing to identify major knowledge gaps and calculate baseline statistics. Key results – The list includes 134 taxa, most of which are linked to closed-canopy forest habitats, while the others are also found in margins and gaps. The forest and non-forest Italian endemic flora differed in terms of taxonomic and life-form distribution. The rate and density of forest endemism increased with decreasing latitude and were highest in Sicily, Calabria, and Basilicata, where paleoendemic mono- or oligotypic genera also occur. Endemic phanerophytes were especially numerous on islands. Beech and deciduous oak forests were the most important habitats, but hygrophilous woodlands also host numerous endemics. Overall, the ecology, biology, and functional traits of the forest endemic taxa are still poorly known. The ratio diploids/polyploids was highest in the south and on the islands. Almost 24% of the taxa were assessed as “Critically Endangered”, “Endangered”, or “Vulnerable”, and 24% were categorized as “Data Deficient”, based on the IUCN system. Increasing frequency and intensity of fires was the most frequent threat. Conclusions – This work can contribute to implement the European forest plant species list and serve as a basis for further research on a unique biological heritage of the continent. However, more knowledge about these globally rare taxa is needed, to support their conservation in changing forest landscapes

Scanning tunneling microscopy of platinum electrode surfaces with different preferred crystallographic orientations

We have used scanning tunneling microscopy to study the surface microtopography of platinum electrodes preferentially oriented by a procedure denoted as electrochemical faceting. The treated specimens show clear reoriented patches on the surface in the form of steps with well-defined orientations separated by terraces of different sizes. The microscopic data obtained by STM correspond well with voltammetric analysis.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada