Asociaciones entre signos clínicos de bruxismo, ansiedad y actividad electromiográfica maseterina utilizando el aparato Bite Strip® en adolescentes de ultimo año de enseñanza media (secundaria) / Association between clinical signs bruxism, anxiety and masseteric electromyographic activity using the Bite Strip® device in adolescents in the last year of high school

El bruxismo consiste en una parafunción del sistema masticatorio. Su prevalencia varía según el medio diagnóstico entre un 6 y 90 por ciento, representando un trastorno de origen central. El gold standard para su diagnóstico es la polisomnografía con un registro de actividad electromiográfica, el que resulta costoso e incómodo para el paciente. Actualmente se ha desarrollado un dispositivo ambulatorio que registra la actividad electromiográfica maseterina (BiteStrip®) el cual sería más económico y cómodo. Existen estudios que demuestran asociación entre bruxismo, estrés y ansiedad y otros que se contradicen, por tanto el objetivo de este trabajo es determinar si existe asociación entre la presencia de signos de bruxismo y ansiedad en individuos de cuarto medio, junto con determinar la utilidad diagnóstica del BiteStrip®. Se utilizó una muestra de 20 alumnos de cuarto medio de un colegio particular de la comuna de Las Condes, Santiago, Chile, a los que se les realizó una encuesta de ansiedad, un análisis de modelos para cuantificar la presencia de facetas de desgaste, y un dispositivo interoclusal de 1mm de espesor para cuantificar actividad de bruxismo. A los que presentaron mayor actividad de bruxismo se les midió la actividad electromiográfica maseterina con un aparato que la registra (BiteStrip®) para cuantificar la intensidad de bruxismo. No se encontraron asociaciones estadísticamente significativas entre ansiedad y signos de bruxismo. En conclusión: En base a la metodología utilizada no se observó asociación entre ansiedad y signos de bruxismo. El BiteStrip resulta un elemento de diagnóstico complementario sencillo, cómodo, útil y fidedigno para el bruxismo, sin embargo, se sugieren más estudios.

Bruxism is a parafunction of masticatory system. The prevalence depends of the diagnosis method, between a 6 and 90 percent. Diagnosis gold standard is polysomnography with an electromyographic study, that results umconfortable and expensive to the patient. BiteStrip® is an exact, economical device for single use to diagnose bruxism. It detects the existence and the intensity of bruxism, and can be used by the patient at home. It has to be applied on the cheek over the masseter muscle. Any bruxism interval will be counted internally and recorded by the BiteStrip. The result represents the area of the recorded intervals and is shown by a permanent electrochemical display. Some studies have show association between bruxism, stress and anxiety, but others do not demonstrate this association. Because of that the objective of this study is to determinate if association between the presence of bruxism signs and anxiety in high school students exists, along with determining BiteStrip® diagnosis utility. A sample of 20 last year high school students of a particular school located in Las Condes, Santiago, Chile was used. To determine anxiety we used a quiz, for attrition we used a model analysis and a interoclusal device to quantify bruxism activity. BiteStrip® was used to determine bruxism intensity in students who present more bruxism activity. We did not find statistically significant association between anxiety and bruxism signs. In conclusion based on the methodology used there was no association between anxiety and signs of bruxism. The BiteStrip is a complementary diagnostic element simple, convenient, useful and reliable for bruxism, however, suggests further studies.

[Transarterial oil chemoembolization for hepatocellular carcinoma, in 100 cases].

Hepatocellular carcinoma (HCC) is a common malignancy with a grave prognosis. Most patients have both the malignant tumor as well as hepatic cirrhosis. Liver transplantation or hepatectomy are considered the only curative procedures, but can be applied in fewer than 10% of patients. In recent decades the most common treatments of HCC are transarterial chemoembolization with oil (TOCE) and percutaneous ethanol injection (PEI). We summarize our retrospective study of 100 patients (mean age 64 +/- 3) treated by TOCE. In 271 procedures between 1989-1998, in 16 patients hepatectomy was combined with TOCE and in 8 PEI was combined with TOCE, while the rest were treated by TOCE alone. Tumor mass was reduced in 36% of those treated by TOCE (tumor volume reduced 24-75%). Alpha-feto protein (AFP) was reduced 25-90% in 20/32 of those with elevated AFP levels. Median survival for the 100 in the entire group was 19 months (10.9 months in those with conservative treatment). Median survival in the 57 in Okuda stage 1 and the 43 in stages 2 or 3 was 30.1 months and 10.9 months, respectively (p < 0.0001). Of the 57 in stage 1, 16 underwent hepatectomy in addition to TOCE and 41 were treated only by TOCE (median survival 15 and 26 months, respectively, p not significant). Comparing Okuda 1 patients treated by TOCE only with the natural history of the disease and historical controls (Okuda 1 patients treated conservatively in 1984) median survival was 26 and 10 months respectively (p < 0.001). The side effects of TOCE were relatively mild. There was 1 fatality (3 days after treatment), and quality of life was maintained. Despite progress in the treatment of HCC by TOCE, PEI, and liver transplantation, long-term survival has remained unsatisfactory.