Effect of short-term increase in occlusal vertical dimension on masticatory muscle electrical activities and pressure-to-pain threshold: A crossover clinical study.

STATEMENT OF PROBLEM: Increasing the occlusal vertical dimension (OVD) is a common procedure in clinical practice. However, few studies have assessed the short-term influence of an increased OVD on the masticatory muscles. PURPOSE: The purpose of this crossover clinical study was to investigate the effect of increased OVD on the electrical activity of masticatory muscles and the pressure-to-pain threshold (PPT) in asymptomatic participants. MATERIAL AND METHODS: Twenty asymptomatic participants (22.7 ±2.39 years of age; 10 men, 10 women) were submitted to an increase in OVD by using interocclusal devices of different thicknesses (3- and 6-mm) for 24 hours. Masticatory muscle activity was assessed with electromyography (EMG), expressed in microvolts (µV), while the participants masticated 2 pieces of latex of different consistency (latex S and H) with and without the device. The PPT was measured with a digital algometer before and after the mastication. The results were assessed by using analysis of variance (ANOVA) and the Tukey honestly significant difference (HSD) test (α=.05). RESULTS: The change of OVD did not significantly affect the electrical activity of the muscles. The latex of hard consistency (latex H) showed higher electrical activity values than the soft texture (latex S). For the working side anterior temporal muscle, a change in the PPT was detected on the day the 6-mm-device was inserted, but for the other muscles, device thickness and latex mastication did not change the PPT. CONCLUSIONS: For a short time, an increase in occlusal vertical dimension did not affect the electrical activity in the masticatory muscles or pressure-to-pain threshold in asymptomatic participants.

Sobredentaduras mandibulares inmediatas: revisión de literatura / Immediate mandibular overdentures: review of literature

Las Prótesis totales convencionales aún cuando bien confeccionadas, pueden presentar deficiencias en la retención, estabilidad y soporte, además de la incomodidad y acumulo de alimentos. Las sobredentaduras sobre implantes fueron consideradas una alternativa para solucionar problemas y experiencias negativas con las prótesis convencionales, así también pueden ser una alternativa a los tratamientos complejos (quirúrgico/protésico) con prótesis fijas soportadas por implantes. Buscando reducir el período de cicatrización para la confección de las prótesis, las investigaciones mostraron altos índices de éxito para los tratamientos con sobredentaduras mandibulares inmediatas sobre implantes, que fueron utilizadas en la rehabilitación de pacientes edéntulos. Este trabajo tiene como objetivo abordar, por medio de una revisión de literatura, la viabilidad de la utilización de sobredentaduras mandibulares implanto retenidas. Los implantes de carga inmediata que retienen una sobredentadura mandibular que ha mostrado ser un método reproducible, previsible y de confianza para restablecer una eficiente función masticatoria a los pacientes totalmente edéntulos

Conventional complete denture even though well confectioned, could present deficiencies in the retention, stability and support, in addition uncomfortable and retention of food below it. The overdentures have been considered an alternative to resolve problems and negative experiences with the conventional dentures, thus also can be an alternative to the complex treatments (surgical/prosthetic) with implant-supported prosthesis. In the attempt to reduce the healing time for the confection of the dentures showed higher rates of success to the implants when immediate mandibular overdentures were used in the rehabilitation of edentulous patients. The aim of this paper was to discuss by means of a Literature review, the viability of the use of mandibular implant-supported overdentures. The immediate mandibular overdentures have been showed like a reproducible method, predictable and confidence to provide an efficient function to the total edentulous patients