The precision of propex Pixi with different instruments and coronal preflaring procedures

Objective:This study aimed to evaluate the influence of the instrument regarding the apical fit and type of the alloy and coronal preflaring procedures in the accuracy of Propex Pixi.Methods: A total of 40 extracted human single-rooted permanent teeth with apical diameters of 200 mu m were selected. A #10 K-file was inserted in the root canal until its end could be observed by a dental microscope to obtain the actual working length (WL). Electronic measurements were performed using Propex Pixi to the root apex ("0.0"). Different file alloys (stainless steel [SS] and nickel titanium [NiTi]) and sizes (#10, #15, and #20) were used before and after coronal flaring. Statistical analysis was performed by a factorial analysis of variance (P <= 0.05).Results: Results showed that the measurements of electronic length (EL) were closer to the actual working length (WL) after coronal flaring (P<0.05). A significant intraclass correlation was observed between EL and WL. In addition, results showed no significant differences between files with different sizes or alloys.Conclusion: Under the conditions of this study, Propex Pixi demonstrated adequate precision. Its accuracy was enhanced by coronal preflaring procedures regardless of the instrument type used (SS or NiTi) and the apical fit.- (undefined

Avaliação da qualidade de tratamentos endodônticos realizados por estudantes de Medicina Dentária

Objectives: To assess radiographically the technical quality of root fillings placed by undergraduate students at the Faculty of Dental Medicine of the University of Porto. Methods: The records of 318 patients were assessed, of which 225 radiographs of root canal fillings in single-rooted teeth were selected. The radiographs were examined using the VixWin Platinum v1.1 Imaging Software (Gendex, USA). The quality of root canal filling was graded as "acceptable" when both length and density were adequate. Procedural errors were registered. Chi-square tests were used for statistical analysis, considering a 0.05 significance level. Results: Root canal fillings were considered acceptable in 53.3% of the cases. There was a greater percentage of adequate density (70.7%) than adequate length (64%). There was a statistically significant association between the quality of the filling and the type of tooth, with maxillary anterior teeth presenting higher quality (p=0.027). The most common reason for inadequate length was short-filling (33%). There was a statistically significant relationship between the academic year and the density of the fillings (p=0.009). Overall procedural errors occurred in 3.6% of the cases, with the most common being ledge formation and apical transportation. Conclusions: The quality of root canal fillings in single-rooted teeth performed by junior dental students at the University of Porto was considered acceptable in 53.3% of cases.Objetivos: Avaliar radiograficamente a qualidade das obturações de tratamentos endodônticos realizados por estudantes do Mestrado Integrado da Faculdade de Medicina Dentária da Universidade do Porto. Métodos: Foram avaliados os registos de 318 pacientes, dos quais foram selecionadas 225 radiografias periapicais de dentes monorradiculares. As radiografias foram examinadas utilizando o software de imagem VixWin Platinum v1.1 (Gendex, EUA). A qualidade do tratamento endodôntico foi classificada como "aceitável" quando o comprimento e a densidade estavam adequados. Os erros iatrogénicos foram registados. O teste qui-quadrado foi utilizado para análise estatística, considerando um nível de significância de 0,05. Resultados: O tratamento endodôntico foi considerado aceitável em 53,3% dos casos. Houve uma maior percentagem de densidade adequada (70,7%) do que comprimento adequado (64%). Verificou-se uma associação estatisticamente significativa entre a qualidade da obturação e o tipo de dente, sendo os dentes anteriores superiores a apresentar maior qualidade (p = 0,027). A razão mais comum para o comprimento inadequado foram as obturações curtas (33%). Verificou-se uma relação estatisticamente significativa entre o ano letivo e a densidade da obturação (p = 0,009). Erros iatrogénicos ocorreram em 3,6% dos casos, sendo os mais comuns a formação de degraus e o transporte apical. Conclusões: A qualidade dos tratamentos endodônticos em dentes monorradiculares realizados por estudantes de Medicina Dentária da Universidade do Porto foi considerada aceitável em 53,3% dos casos.- (undefined

Peripapillary Retinal Nerve Fiber Layer Thickness and Peripheral Microcirculation in Raynaud’s Disease

Purpose: Normal-tension glaucoma has been associated with systemic vascular diseases such as peripheral vasospasm. This study aims to evaluate the influence of peripheral vasospasm on the thickness of the retinal nerve fiber layer (RNFL) in Raynaud's disease (RD), and the correlation between global RNFL and peripheral microcirculation features in RD patients. Methods: Observational cross-sectional study of 18 patients (35 eyes) with a diagnosis of RD followed in our clinic, and 20 healthy controls (39 eyes). RNFL parameters were obtained using spectral domain optical coherence tomography (SD-OCT Spectralis®, Heidelberg). Global and sectorial peripapillary RNFL thickness were registered. Age, gender, refractive error, best-corrected visual acuity and intraocular pressure were determined, and slit-lamp biomicroscopy and fundus examination were performed. Nailfold videocapillaroscopy (NC) was performed in the RD group to characterize capillary morphology and blood flow. Mann-Whitney and Fisher's exact tests were used for statistical analysis. Statistical significance level was set at p<0.05 (two-sided). Results: There was no significant difference in the global RNFL between RD patients and the control group (p=0.35). The presence of avascular areas in NC was associated with a lower global RNFL thickness (p=0.026). Conclusion: The association between avascular areas in NC and the lower global RNFL thickness in RD patients suggests that systemic vasospasm severity may be related to optic nerve damage propensity. Therefore, its presence in NC may identify RD patients at risk for optic nerve head damage. A larger sample with a long-term study is needed to support the clinical and therapeutic implications of our findings.info:eu-repo/semantics/publishedVersio

Simple and highly discriminatory microsatellite-based multiplex PCR for Aspergillus fumigatus strain typing

AbstractThe answers to important questions concerning Aspergillus fumigatus pathogenicity, transmissions routes and efficacy of treatments require highly discriminating and reproducible genotyping methods. The present study was aimed at improving microsatellite methodology for A. fumigatus typing by reducing the task of strain identification to a single multiplex reaction and by selecting highly accurate short tandem repeat polymorphisms. A set of eight primer pairs was used for the genotype determination of 116 clinical isolates of A. fumigatus obtained from three healthcare centres. A new, automated and highly discriminatory typing method is described for A. fumigatus strains. The optimized multiplex PCR was successfully performed with all tested clinical strains and showed a discriminatory power of 0.9997 among presumably unrelated isolates. The comparison of groups of strains from different health centres showed that 99.6% of the genotypic variation was present within groups. Strains with the same genotype were isolated from the same patient, sometimes recovered more than 1 year later. A few cases of patients at the same clinic unit carrying strains of identical genotype strongly suggested colonization by A. fumigatus during their hospitalization. Specific measures must therefore be taken in order to prevent and restrict such incidents

First experience of an undergraduate dental student with a reciprocating system in simulated root canals - a pilot study

Rotary instrumentation has been proposed in undergraduate teaching. The aim of this study was to evaluate student’s performance, through the obturation quality and treatment time, in a sequential range of L-simulated root canals. A senior undergraduate dental student sequentially prepared randomly numbered canals from 1 to 40, with the WaveOne Gold glider and primary file, according to the manufacturer instructions. A gutta-percha cone matched with the finishing instrument and epoxy resin-based sealer (AH Plus) was selected for the obturation. Three independent observers evaluated the obturation quality according to both density and length. Active, total instrumentation and obturation times were also measured. Statistical analysis was obtained by Mann–Whitney and Kruskal–Wallis tests with a significance level of p < 0.05. The quality of the obturation was independent of the number of prepared canals with adequate length and density in 87.5% of the prepared canals. Both active and total instrumentation, as well as obturation times, reduced significantly as the number of the prepared canals by the student increased (p < 0.05). The use of WaveOne Gold instrumentation and matched cone obturation by an inexperienced operator provided an adequate obturation quality in most of the curved simulated canals. The working time was significantly reduced through a short learning curve

Evaluating the Concentration of a Candida albicans Suspension

Objective: The objective of this study was to develop a reproducible method of establishing the concentration of yeast cells per milliliter of solution

Validation of a suggested pre-operative protocol for the prevention of traumatic dental injuries during oroendotracheal intubation: a pilot study

The aim of this study was to develop a protocol for oral pre-operative registration and dental risk assessment by the anaesthesiologist, determining its reliability through the inter-observer agreement between a senior dental student and an internal physician specializing in anaesthesiology. A convenience sample consisting of 35 patients was selected. These were observed during the anaesthesiology consultation, at Hospital de São João, Porto, Portugal. The protocol included a self-administered questionnaire and a brief clinical examination by the two observers. A descriptive analysis (qualitative and quantitative variables) was performed. The Fleiss Kappa index was used to measure the degree of agreement between the two observers. In most of the parameters defined, the agreement presented Kappa index values between 0.6 and 1, corresponding to good and excellent correlation, respectively. The general oral status was considered “poor”, with a great number of missing teeth, namely the upper central and lateral incisors. The proposed pre-anaesthetic protocol can be a reliable tool for the anaesthesiologists, which suggests the relevancy of incorporating interdisciplinary training between future health professionals. Further research is needed to assess its implementation, providing information about the pre-operative oral status, preventing intraoperative damage and potential medicolegal litigation

Optic nerve head drusen: same presentation, different workup

Objective/Purpose: To report two young patients with optic nerve head drusen in wich one was interpreted initially as pappiledema. Discuss the OCT and the autofluorescence retinography optic nerve head drusen characteristics. Materials/Patients: Patient 1: A 10-year-old boy who was noted at follow-up ophthalmology consultation to have an abnormal optic nerve head. He refers a recent episode of neck pain. His past medical history is irrelevant. He has a strabismic amblyopia due to anisometropia. Fundoscopy showed bilateral disc enlargement that wasn t describe in previous consultation being interpreted as papilledema. Observation by Neuropediatry as well as the CT scan were unremarkable. Bilateral optic disc drusen were confirmed on B-scan ultrasonography, autofluorescence retinography and retinal nerve fiber layer on Stratus- OCT®. Patient 2: A 14-year-old girl went on a routine ophtalmology examination. Her past medical and ocular history were irrelevant. On examination visual acuity was 10/10 in both eyes. Fundoscopy showed bilateral disc enlargement being interpreted as optic nerve head drusen. Bilateral optic nerve head drusen were confirmed on B-scan ultrasonography, autofluorescence retinography and retinal nerve fiber layer on Stratus-OCT®. Methods: B-scan ultrasonography, autofluorescence retinography and Stratus-OCT imaging were obtained. Results and Conclusion Both patients were assymptomatic. With non-invasive readily available exams, such as ultrasonography and OCT practioners must rule out optic nerve head before costly and invasive exams , even when there is a history and fundoscopy highly suggestible of papilledema. Optic nerve head drusen were first described in 1868 by Liebreich. They are mostly bilateral and assymptomatic, although some degree of visual field defect can be shown. Most cases of pseudopapilledema are due to the presence of optic nerve head drusen, there are some clinical characteristics that can help to differenciate one from another but the use of recent technology is needed to confirm the diagnosis

Iris bombe with dramatic visual acuity improvement after laser peripheral iridotomy

Objective/Purpose To describe a case report on a patient with iris bombe with a dramatic visual acuity improvement following iridotomy. Materials/Patients A 34-year-old man, with a background of ankylosing spondylitis, who had been hospitalized in other Institution for 3 weeks in the previous month due to uveitis and on topical steroids, presented with decrease in visual acuity in his right eye (OD) since the eve. On ophthalmic examination, visual acuity was counting fingers at 2 meters in OD. The biomicroscopy of the right eye revealed inflammatory cells (Grade 3+) in the anterior chamber and extensive posterior synechae with iris bombe and iridocorneal touch in all quadrants, also presented a transparent cornea and an intraocular pressure of 30 mmHg. The anterior chamber depth was 0.81 mm with an anteriorly dislocated anterior surface of the crystalline lens as obtained with Oculus Pentacam®. A laser peripheral iridotomy was performed and medicated with topical combination of timolol and dorzolamide bid and oral acetazolamide 500 mg bid. Methods Stratus-OCT and Oculus Pentacam imaging were obtained. Results and Conclusion One day after the iridotomy the patient presented visual acuity of 8/10 in OD. The biomicroscopy of the right eye revealed inflammatory cells (Grade 3+) in a large anterior chamber, a patent iridotomy and an intraocular pressure of 12 mmHg. The anterior chamber depth was 2.52 mm. Iris bombe and acute pupillary block glaucoma are uncommon severe complications of uveitis. The initial treatment for extensive posterior synechiae is pupillary dilation in order to free a portion of the iris and reduce pupillary block. Many times laser iridotomy is required for resollution and prevention of recurrence of pupillary block. In this patient the initial visual loss is probably related to a myopization due to the anteriorly dislocated crystalline that resolved rapidly with the reformation of the anterior chamber