Purpose:The present study aimed to analyze in a Spanish population sample the compliance of the anterior maxillary teeth to the dental esthetic proportions described in the literature. Methods: Photographs of the smiles of 78 individuals were calibrated and digitally analyzed considering the following proportions: golden proportion (GP), recurring esthetic dental (RED), golden percentage (GPG), Preston's proportion and Modified golden percentage (MGPG). For statistical analysis, the t-test of an independent sample was applied, and compliance percentages for each standard were recorded. Results: The existence of RED 70% or 80% has not been registered. The percentages of compliance with GP were within a range between 0% and 16%. The mean tooth width ratios were adjusted to the values described by Preston (P > 0.05), but the compliance percentages were low (3.33-25%). GPG only presented high percentages of compliance in the lateral incisors (53.33-62.5%). MGPG showed the highest percentages of compliance (50-68%). Conclusion: After analyzing a Spanish population sample using smile photographs for the first time, GP, RED, GPG and Preston's proportion standards are not fulfilled and therefore, not suitable for treatments that seek a smile that reproduces natural principles. However, the values designated by MGPG with a deviation of ±1% are largely applicable for treatments that aim for a natural smile.
The use of fiberglass in dentistry has increased due to the improvements in the development of adhesive techniques reducing the cost of treatment and avoiding abutment tooth craving. The present study aims to evaluate the clinical usefulness of the new technique to fabricate a direct fiber-reinforced composite bridge (FRCB) over a long period of time. Twenty-one FRCB were performed with the new direct technique on 21 patients with a mean age of 58.85 years and female predominance in the Faculty of Dentistry of Oviedo (Spain). The framework design releases the embrasures allowing adequate interproximal brushing, avoidance of periodontal disease and interproximal caries. A baseline examination was performed and the patients were examined regularly at six-month intervals (nine years’ follow-up). The restorations were also evaluated by an examiner using parameters to check their stability, longevity and the lack of periodontal disease. The most frequent location was the maxillary premolar region and the purpose of the restorations was to give a definitive bridge in 100% of the patients. Only one total debonding of the prostheses was detected during the observation period at 24 months and three partial adhesive–cohesive veneering composite fractures at the pontic after 60, 72 and 84 months, respectively. Kaplan–Meier was performed to detect the overall survival rate of the restorations at the end of the follow-up. Nine-year survival rates for the FRCB was 95.2%. All the cases had a clinically acceptable periodontal condition and an interproximal absence of caries in the abutment teeth. Currently, this type of restoration allows a minimally invasive aesthetic and is an affordable procedure, being a good alternative to other types of treatments.
Spinocerebellar ataxia 36 (SCA36) is a type of repeat expansion-related neurodegenerative disorder identified a decade ago. Like other SCAs, the symptoms of SCA36 include the loss of coordination like gait ataxia and eye movement problems, but motor neuron-related symptoms like muscular atrophy are also present in those patients. The disease is caused by a GGCCTG hexanucleotide repeat expansion in the gene Nop56, and the demographic incidence map showed that this disease was more common among the ethnic groups of Japanese and Spanish descendants. Although the exact mechanisms are still under investigation, the present evidence supports that the expanded repeats may undergo repeat expansion-related non-AUG-initiated translation, and these dipeptide repeat products could be one of the important ways to lead to pathogenesis. Such studies may help develop potential treatments for this disease.
Paracentrotus lividus is a sea urchin with an important ecological role in the Cantabrian Sea ecosystem, where its populations are in severe decline and the regional government has implemented a population restoration strategy with the aim of preserving this valuable marine resource. In this study, genetic monitoring was conducted for the first time in the central area of the southern Bay of Biscay to describe the genetic diversity patterns of P. lividus and to assess the potential impacts of conservation and mitigation actions on the wild gene pool. Genetic analyses were performed using the mitochondrial cytochrome b gene and microsatellite loci. Asturian localities showed significant genetic heterogeneity, possibly due to genetic drift, and seemed to constitute a differentiated management unit with regard to other areas of the species’ distribution. The genetic diversity analyses comparing wild samples with those subjected to restoration experiments did not show significant negative effects on restored localities. Sea urchins from hatcheries represented 3.5% of the total recaptured individuals (95% accuracy). Even when low hatchery contributions were detected in this work, the results pointed to the necessity of improving the initial autochthonous breeder genetic pool and the aquaculture strategies applied when restoring wild populations to avoid future unwanted negative effects on wild gene pools.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.