Evaluation of a New Dental Implant Cervical Design in Comparison with a Conventional Design in an Experimental American Foxhound Model

This is the peer reviewed versión of the following article: "Evaluation of a New Dental Implant Cervical Design in Comparison with a Conventional Design in an Experimental American Foxhound Model ", which has been published in final form at [doi:10.3390/ma11040462],. This article May be used for non-comercial pipotes in accordance with Wiley Terms an Conditions for Use of Self-Archived Versions.Odontologí

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Evaluación histológica e histomorfométrica del contacto del hueso-implante en implantes dentales de zirconia modificados por láser de femtosegundo vs implantes de zirconia, en hueso cicatrizado : estudio experimental en perros fox hound a tres meses

El objetivo del presente estudio fue evaluar las características de superficie de implantes de zirconia modificados por láser de femtosegundo, las características histológicas e histomorfométricas del contacto hueso- implante, densidad ósea y la altura de la cresta ósea. Los segundos, terceros, cuartos premolares y el primer molar mandibular de seis perros de raza Fox Hound fueron extraídos de manera bilateral. Dos meses después se colocaron de forma aleatoria 48 implantes dentales, divididos en 3 grupos de 16 implantes: grupo Control, (Implantes de zirconio arenados en la porción intraósea), Grupo A (Implantes de zirconio arenados y tratados por láser en la zona del cuello en la porción intraósea) y Grupo B (Implantes de zirconio arenados y tratados por láser en toda la porción intraósea). Los implantes fueron ferulizados mediante provisionales de acrílico de alta resistencia. Se evaluaron mediante técnicas histológicas e histomorfométricas los parámetros histológicos de nivel del hueso crestal (RBCL), contacto hueso implante (BIC), y densidad ósea (DO) al mes y a los tres meses de la inserción. Todos los implantes se osteointegraron y sobrevivieron al período establecido de estudio (1 y 3 meses). Los valores del PTV del Periotest obtenidos para el grupo Control fueron -5,750,22 grupo A -6,1250,26 Grupo B -7,6250,27. La reabsorción crestal fue menor el primer mes, con valores entre 0,84mm0,25mm en todos los grupos. En el tercer mes la reabsorción crestal se incrementó ligeramente en todos los grupos con valores entre 1,15mm0,78mm. La composición de la superficie de los implantes de zirconio mostró principalmente óxido de zirconio (60,2 ± 0,7%) así como otros elementos tipo Carbono (19,7% ± 0,8%), Oxígeno (12,6% ± 0,5%) y Aluminio (4,3% ± 0,9%); el Carbono y Aluminio se observó en cantidades más pequeñas en los implantes de zirconio con microsurcos, (C= 0,3%±0,12% 1,6%±0,35% 19,7% ± 0,8%; Al= 0,18% ± 0,1% 1,16%±0,2% 4,3% ± 0,9%) mientras que la presencia de Oxígeno aumentó (23,1%± 0,12% 22,7% ± 0,2% 12,6% ± 0,5%). El elemento O se incrementó en los grupos A y B, comparados con el grupo Control. (*p<0.05). EL elemento Ca se mantuvo constante a lo largo de los períodos de estudio entre 14-17% así como el P que se mantuvo constante entre 3-6%. Otros elementos presentes como el Y y el Hf presentaban los menores valores con un 3% 1% y entre 1,5-1,7% respectivamente. El contacto hueso implante fue mayor para los implantes del grupo B durante el primer mes y durante el tercer mes. No se evidenciaron diferencias entre el grupo Control y el grupo A en los períodos de tiempo estudiados. Grupo Control 31,786% ± 5,89094% Grupo A 33,732% ± 3,41371% Grupo B 44,6819% ± 4,65768%. Esta tendencia continúa al registrar los valores de las mediciones del BIC a los 3 meses, donde los valores de BIC del Grupo B significativamente mayores que el resto de los grupos ( Grupo Control 37,864% ± 3,01417% Grupo A 38,265% ± 1,78365% Grupo B 47,9423% ± 3,15423%). Nuestros resultados sugieren que la rugosidad superficial de implantes de zirconio se incrementa significativamente con el tratamiento láser. A mayor superficie tratada por láser mayor rugosidad superficial, produciendo también una disminución de elementos Carbono y Aluminio en la superficie y un aumento de la presencia de Oxígeno. El tratamiento de la superficie de los implantes de zirconio mediante la aplicación del láser de femtosegundo, aumenta la estabilidad de los implantes y produce un incremento significativo de los valores de contacto-hueso-implante (BIC). PURPOSE: The aim of the present study was to evaluate the characteristics of Zirconia implant surfaces modified by laser as well as the histology of peri-implant soft tissue, the crestal bone level, bone-to-implant contact and bone density. MATERIAL and METHODS: A total of 48 dental implants were used in this study. Following the extraction of premolars (P2,P3,P4) and molars (M1), and a two-months healing period, the remaining 48 implants were inserted randomly in both sides of the lower jaw of six Fox Hound dogs divided into groups of 16 each: Control Group (Zirconia implants with sandblasted surface on endosseus portion), Test A (Zirconia implants with sandblasted and treated by laser surface only in the neck of the endosseous portion), Test B (Zirconia implants with sandblasted and treated by laser surface on the endosseus portion of the implant).. Implants were splinted using high resistente acrylic temporary prosthesis. The histological parameters of level of crestal bone (CB), bone-to-implant contact (BIC) and bone density were evaluated by histomorphometric techniques 3 months after surgery. RESULTS: All implants were osseointegrated and survived the prescribed period of study (1 and 3 months). PTV values of Periotest ® obtained for the Control Group were -5.75 ± 0.22 22.7% ± 0.2%> 12.6% ± 0.5%). The O element increased in groups A and B, compared with the control group. (* P <0.05). The element Ca is kept constant throughout the study periods between 14-17% and the P which remained constant between 3-6%. Other elements present as Y and Hf had the lowest values with 3% ± 1% and from 1.5 to 1.7%, respectively. The bone implant contact was greater for the implants in group B during the first month and during the third month. There were no differences between the control group and group A in the time periods studied. Control Group 31.786% ± 5.89094% <Group A 33.732% ± 3.41371% <Group B 44.6819% ± 4.65768%. This trend continues to record the values of BIC measurements at 3 months, where the values of BIC Group B significantly higher than the other groups (Control Group 37.864% ± 3.01417% <Group A 38.265% ± 1 , 78365% <Group B 47.9423% ± 3.15423%). CONCLUSION: Our results suggest that the surface roughness of zirconium implants increases significantly with the laser treatment. The higher the laser treated surface greater surface roughness, producing also a decrease in carbon and aluminum elements on the surface and an increase in the presence of oxygen. The surface treatment of zirconium implants by application of femtosecond laser, increase implant stability and produces a significant increase of the values of contact-bone-implant (BIC)

Evaluation of a New Dental Implant Cervical Design in Comparison with a Conventional Design in an Experimental American Foxhound Model

The aim of this study was to evaluate osseointegration and crestal bone height in implants with a triangular cervical design in comparison with a standard rounded cervical design. The control group consisted of 24 implants with a standard cervical design, and the test group of 24 implants with a triangular cervical design. The implants were inserted in healed bone in six American Foxhounds. Crestal bone height and tissue thickness in the cervical portion were measured after 12 weeks healing. Data analysis found mean crestal bone loss of: 0.31 ± 0.24 mm on the buccal side, 0.35 ± 0.14 mm on the lingual in the test group, and 0.71 ± 0.28 mm buccal loss, and 0.42 ± 0.30 mm lingual in the control group; with statistically significant differences on the buccal aspect (p = 0.0019). Mean tissue thickness in the test group was 1.98 ± 0.17 mm on the buccal aspect, and 2.43 ± 0.93 mm in the lingual; in the control group it was 2.48 ± 0.61 mm buccal thickness, and 2.88 ± 0.14 mm lingual, with significant differences on both aspects (p = 0.0043; p = 0.0029). The results suggest that greater thickness of peri-implant tissue can be expected when the triangular cervical implant design is used rather than the standard cervical design

Children living with HIV in Europe: do migrants have worse treatment outcomes?

International audienceTo assess the effect of migrant status on treatment outcomes among children living with HIV in Europe