An analysis of the decision-making process for single implant treatment in general practice

Background: There is little information on the decision-making process for single implant treatment in general practice. Aim: To study the incidence of and the factors associated with the decision to perform single implant treatment after tooth extraction by general practitioners in a private, fee-for-service setting. Methods: One hundred practitioners with a general dental practice in Ghent were randomly selected from an official list received by the Belgian Social Security Institute. Clinicians were asked to fill in a study form for every single extraction they performed during an 8-week period. The study form related to the treatment decision as discussed with the patient and a number of patient- and clinician-related factors. The association of these factors with single implant treatment was evaluated using univariate tests and logistic regression. A decision-tree was also constructed with the predictors from the regression analysis as independent variables. Results: Ninety-four general dentists (52 males, 42 females; mean age 49; range 24–68)agreed to participate and extracted 1180 single teeth in an equal number of patients (50% males, 50% females; mean age 53; range 18–90). The main reasons for tooth loss were caries (48%) and periodontal disease (28%). At the time of extraction tooth replacement was deemed necessary in half of the patients and are movable partial denture was chosen in 55% of them. Similar frequencies were found for fixed partial denture (23%) and single implant treatment (21%). Although the vast majority of patient- and clinician-related factors showed a significant association with the latter on the basis of univariate tests, logistic regression only identified seven predictors. These included location of the extracted tooth, number of missing teeth, regular supportive care, bone loss at adjacent teeth, restoration level of adjacent teeth, gender of the clinician and dentists’ experience in implant prosthetics. The decision tree identified bone loss at adjacent teeth and number of missing teeth as the most important predictors for single implant treatment. Conclusions and clinical implications: If tooth replacement was deemed necessary at the time of extraction, a single implant was the treatment of choice in only one-fifth of the patients. Mainly oral factors had an impact on the decision-making process in contrast to patients’ background and medical factors. Dentists’ experience in implant prosthetics also showed a positive association with single implant treatment as opposed to dentists’ experience in implant surgery

Long-term clinical, aesthetic and patient-reported outcomes of single implants in the anterior maxilla

Single implant replacements with dental implants are frequently performed and have a good long-term prognosis. Historically, the following criteria for implant success were widely used: implant in situ, no mobility, no radiolucency, no more than 0.2 mm vertical bone loss yearly after the first year of function, no pain, no peri-implant inflammation/infection. Today implant survival is not considered the only determinant of clinical success. However, peri-implant bone maintenance is important to maintain stable aesthetics. In an evolving society patients are more critical on the aesthetics and peri-implant health. Also, psycho-social factors are considered important and go beyond implant survival. This PhD thesis highlighted some of the shortcomings in the literature by means of the execution of a number of short-term clinical studies as well as prolongations of clinical trials previously initiated at Ghent University Hospital. The clinical research papers presented in this PhD thesis are based on long-term clinical studies that were initiated a decade ago. The initial one year results were published in a PhD thesis defended successfully in 2011 by Dr Filiep Raes

Oral health-related quality of life changes after placement of immediately loaded single implants in healed alveolar ridges or extraction sockets : a 5-year prospective follow-up study

Objectives: The impact of single implants on oral health-related quality of life (OHRQoL) is scarcely investigated, especially when combined with immediate placement and loading in extraction sockets. The aim was to describe prospectively the changes of OHRQoL with single implants placed in the esthetic zone in healed ridges or in extraction sockets after 5 years. Material and Methods: Ninety-six patients, enrolled at three clinical centers, received 102 single implants placed in a healed ridge (n = 54 implants/50 patients) or in extraction sockets (n = 48 implants/46 patients). Implants were immediately provisionalized, and permanent crowns were cemented after 12 weeks. Oral health impact profile questionnaires (OHIP-14) were completed before surgery, after 1 (provisional crown), 6 (permanent crown), 12 and 60 months, respectively. The overall OHIP-14 score pertains to seven domains with two items each and was assessed on a Likert scale of 0–4 (0 = never and 4 = very often). The evolution of the total OHIP-14 score and changes within all OHIP domains over time and between groups were assessed with a linear mixed-effect model analysis. Results: After 5 years, overall implant survival was 98%. The total OHIP-14 score for both groups combined decreased from 0.50 at baseline to 0.17 at 6 months (P < 0.001), indicative of improvement. For both groups, this remained stable up to 5 years (P = 0.41). However, after 5 years, the total OHIP-14 score revealed a statistically significantly higher improvement in the healed group compared with the extraction group (P = 0.027). Conclusion: Missing a single tooth in the maxillary esthetic zone leads to limited OHRQoL problems as reflected by a low overall OHIP score. However, OHRQoL improves less in the extraction group, reflecting that replacing a missing tooth is perceived as more beneficial than replacing a present tooth

Nonrandom divergence of gene expression following gene and genome duplications in the flowering plant Arabidopsis thaliana

BACKGROUND: Genome analyses have revealed that gene duplication in plants is rampant. Furthermore, many of the duplicated genes seem to have been created through ancient genome-wide duplication events. Recently, we have shown that gene loss is strikingly different for large- and small-scale duplication events and highly biased towards the functional class to which a gene belongs. Here, we study the expression divergence of genes that were created during large- and small-scale gene duplication events by means of microarray data and investigate both the influence of the origin (mode of duplication) and the function of the duplicated genes on expression divergence. RESULTS: Duplicates that have been created by large-scale duplication events and that can still be found in duplicated segments have expression patterns that are more correlated than those that were created by small-scale duplications or those that no longer lie in duplicated segments. Moreover, the former tend to have highly redundant or overlapping expression patterns and are mostly expressed in the same tissues, while the latter show asymmetric divergence. In addition, a strong bias in divergence of gene expression was observed towards gene function and the biological process genes are involved in. CONCLUSION: By using microarray expression data for Arabidopsis thaliana, we show that the mode of duplication, the function of the genes involved, and the time since duplication play important roles in the divergence of gene expression and, therefore, in the functional divergence of genes after duplication

A questionnaire survey of radiological diagnosis and management of renal dysplasia in children

Background: The condition called renal dysplasia is considered to be a frequent cause of chronic kidney disease in children. Formally, it is defined by histological parameters. In current nephrology practice, however, the appearance of the kidneys on ultrasound scanning is often used as a basis for the diagnosis. Methods: The European Society for Pediatric Nephrology Working Group on Congenital Anomalies of the Kidney and Urinary Tract hypothesized that the current diagnostic approach with regard to renal dysplasia was not homogeneous. Accordingly, we here report the results of a survey targeting pediatric nephrologists with 12 questions regarding their perceptions of the ultrasonographic characteristics of renal dysplasia and further tests that they might undertake. Results: Of almost 1200 physicians who successfully received the invitation, 248 from 54 countries completed the survey. There was a notable lack of homogeneity regarding the ultrasonographic diagnosis of renal dysplasia and also of follow-up tests, including genetic testing and further radiology. Conclusions: Based on the responses to this large survey, a picture emerges of nephrologists' current clinical practice with regard to renal dysplasia. The Working Group considers that these results serve as an important sounding board which can provide the basis for more definitive recommendations regarding the challenges to clinical diagnosis and diagnostic follow-up of this important condition

Exploring nucleo-cytoplasmic large DNA viruses in Tara Oceans microbial metagenomes

Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2–1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 104–105 genomes ml−1 for the samples from the photic zone and 102–103 genomes ml−1 for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts

A Holistic Approach to Marine Eco-Systems Biology

With biology becoming quantitative, systems-level studies can now be performed at spatial scales ranging from molecules to ecosystems. Biological data generated consistently across scales can be integrated with physico-chemical contextual data for a truly holistic approach, with a profound impact on our understanding of life [1]–[5]. Marine ecosystems are crucial in the regulation of Earth's biogeochemical cycles and climate [6],[7]. Yet their organization, evolution, and dynamics remain poorly understood [8],[9]. The Tara Oceans project was launched in September 2009 for a 3-year study of the global ocean ecosystem aboard the ship Tara. A unique sampling programme encompassing optical and genomic methods to describe viruses, bacteria, archaea, protists, and metazoans in their physico-chemical environment has been implemented. Starting as a grassroots initiative of a few scientists, the project has grown into a global consortium of over 100 specialists from diverse disciplines, including oceanography, microbial ecology, genomics, molecular, cellular, and systems biology, taxonomy, bioinformatics, data management, and ecosystem modeling. This multidisciplinary community aims to generate systematic, open access datasets usable for probing the morphological and molecular makeup, diversity, evolution, ecology, and global impacts of plankton on the Earth system

Open science resources for the discovery and analysis of Tara Oceans data

Le " Tara Expéditions" organise des expéditions pour étudier et comprendre l'impact des changements climatiques sur nos océans.International audienceThe Tara Oceans expedition (2009–2013) sampled contrasting ecosystems of the world oceans, collecting environmental data and plankton, from viruses to metazoans, for later analysis using modern sequencing and state-of-the-art imaging technologies. It surveyed 210 ecosystems in 20 biogeographic provinces, collecting over 35,000 samples of seawater and plankton. The interpretation of such an extensive collection of samples in their ecological context requires means to explore, assess and access raw and validated data sets. To address this challenge, the Tara Oceans Consortium offers open science resources, including the use of open access archives for nucleotides (ENA) and for environmental, biogeochemical, taxonomic and morphological data (PANGAEA), and the development of on line discovery tools and collaborative annotation tools for sequences and images. Here, we present an overview of Tara Oceans Data, and we provide detailed registries (data sets) of all campaigns (from port-to-port), stations and sampling events

BRCC36A is epistatic to BRCA1 in DNA crosslink repair and homologous recombination in Arabidopsis thaliana

BRCA1 is a well-known tumor suppressor protein in mammals, involved in multiple cellular processes such as DNA repair, chromosome segregation and chromatin remodeling. Interestingly, homologs of BRCA1 and several of its complex partners are also found in plants. As the respective mutants are viable, in contrast to mammalian mutants, detailed analyses of their biological role is possible. Here we demonstrate that the model plant Arabidopsis thaliana harbors two homologs of the mammalian BRCA1 interaction partner BRCC36, AtBRCC36A and AtBRCC36B. Mutants of both genes as well as the double mutants are fully fertile and show no defects in development. We were able to show that mutation of one of the homologs, AtBRCC36A, leads to a severe defect in intra- and interchromosomal homologous recombination (HR). A HR defect is also apparent in Atbrca1 mutants. As the Atbrcc36a/Atbrca1 double mutant behaves like the single mutants of AtBRCA1 and AtBRCC36A both proteins seem to be involved in a common pathway in the regulation of HR. AtBRCC36 is also epistatic to AtBRCA1 in DNA crosslink repair. Upon genotoxic stress, AtBRCC36A is transferred into the nucleus