Influence of diameter in the stress distribution of extra-short dental implants under axial and oblique load: a finite element analysis

Aim: This study evaluated the influence of a wide diameter on extra-short dental implant stress distribution as a retainer for single implant-supported crowns in the atrophic mandible posterior region under axial and oblique load. Methods: Four 3D digital casts of an atrophic mandible, with a single implant-retained crown with a 3:1 crown-to-implant ratio, were created for finite element analysis. The implant diameter used was either 4 mm (regular) or 6 mm (wide), both with 5 mm length. A 200 N axial or 30º oblique load was applied to the mandibular right first molar occlusal surface. The equivalent von Mises stress was recorded for the abutment and implant, minimum principal stress, and maximum shear stress for cortical and cancellous bone. Results: Oblique load increased the stress in all components when compared to axial load. Wide diameter implants showed a decrease of von Mises stress around 40% in both load directions at the implant, and an increase of at least 3.6% at the abutment. Wide diameter implants exhibited better results for cancellous bone in both angulations. However, in the cortical bone, the minimum principal stress was at least 66% greater for wide than regular diameter implants, and the maximum shear stress was more than 100% greater. Conclusion: Extra-short dental implants with wide diameter result in better biomechanical behavior for the implant, but the implications of a potential risk of overloading the cortical bone and bone loss over time, mainly under oblique load, should be investigated

Sintomatología depresiva en pacientes con fibromialgia / Depressive symptoms in fibromyalgia

Introducción: La fibromialgia es una entidad frecuente en la práctica clínica y se ha considerado que está asociada con desórdenes psiquiátricos, en particular con depresión, lo cual podría tener un impacto en el tratamiento de esta entidad. Objetivo: Evaluar la prevalencia de síntomas depresivos en pacientes con fibromialgia. Diseño: Estudio observacional y de tipo transversal. Lugar: Servicio de Reumatología, Hospital Departamental María Auxiliadora. Participantes: Pacientes de ambos sexos con diagnóstico de fibromialgia. Intervenciones: Se utilizó la escala de Hamilton para la depresión (HDRS) y el recuento de puntos dolorosos para fibromialgia. Principales medidas de resultados: Porcentaje de pacientes con síntomas depresivos. Puntaje total de la HDRS en relación al recuento de puntos dolorosos. Resultados: La edad promedio fue 54,9 ± 14 años, 80 por ciento fue del sexo femenino y el número promedio de puntos dolorosos, 14,4 ± 1,5. El 32,7 por ciento de pacientes no tenía síntomas de ánimo depresivo, en 27,7 por ciento los síntomas fueron leves, en 30,9 por ciento moderados y solo en 9 por ciento severos. Ningún paciente presentó síntomas compatibles con ánimo depresivo muy severo. Encontramos una correlación significativa entre el número de puntos dolorosos y el puntaje de la escala HDRS (r= 0,740), p< 0,001. Conclusiones: Los síntomas depresivos severos se encuentran en una proporción baja en pacientes con fibromialgia y parecen estar directamente asociados con el número de puntos dolorosos.

Introduction: Fibromyalgia is a common musculoskeletal problem in clinical practice and is associated with psychiatric disorders. The association with major depression potentially has therapeutic implications. Objective: To determine the prevalence of depressive symptoms in a sample of patient with fibromyalgia. Design: Observational and transversal study. Setting: Rheumatology Department, Maria Auxiliadora Hospital, Lima, Peru. Participants: Fifty-five patients of both sexes with fibromyalgia. Interventions: Fibromyalgia tender points count and use of Hamilton Rating Scale for Depression (HDRS). Main outcome measures: Percentage of depressive symptoms. Total HDRS score in relation to tender point count. Results: Average age was 54,9 ± 14 years, 80 per cent were females, and the average tender point score was 14,4 ± 1,5. The HDRS score did not show depression mood symptoms in 32,7 per cent, 27,7 per cent had mild symptoms, 30,9 per cent moderate and 9 per cent severe symptoms. In no patient depression mood symptoms were considered very severe. There was significant correlation between the number of tender points and HDRS score (r= 0,740), p< 0,001. Conclusions: Severe or very depressive symptoms are infrequent in fibromyalgia and depression mood symptoms seem to correlate positively with the number of tender points.

Genetic variability of Herpailurus yagouaroundi, Puma concolor and Panthera onca (Mammalia, Felidae) studied using Felis catus microsatellites

We used four microsatellite loci (Fca08, Fca45, Fca77 and Fca96) from the domestic cat, Felis catus, to investigate genetic variability in specimens of Herpailurus yagouaroundi (jaguarundi, otter cat, eyra), Puma concolor (cougar, mountain lion, puma) and Panthera onca (jaguar) held in various Brazilian zoos. Samples of DNA from the cats were PCR amplified and then sequenced before being analyzed using the CERVUS program. Our results show a mean polymorphic information content (PIC) of 0.83 for H. yagouaroundi, 0.66 for P. concolor and 0.69 for P. onca and a mean of 10.3 alleles for the Fca08 locus, 5.3 for Fca 45, 9 for Fca 77 and 14 for Fca 96. These results indicate a relatively high level of genetic diversity for the specimens studied.