ABSTRACT
Manipulation of implant surface characteristics constitutes a promising strategy for improving cell growth and tissue response on a variety of materials with different surface topographies. Mesenchymal progenitor cells with a capacity to respond to titanium surface stimuli and differentiate into osteoblasts were used to perform comparative tests between two different implant topographies, including their functional interaction with pre-osteoblasts directly seeded onto the implants. Functional analysis of nanostructured implant surfaces was performed by in vitro assay analysis. The machined surface of titanium implants (mach group) was used as a control and compared with a nanoparticle HA activated surface implant (nano group), developed by the deposition of pure crystalline hydroxyapatite. Cell culture on the nano group surface resulted in higher cell adhesion and cultured osteoblast viability compared with the mach group. Scanning electron microscope (SEM) images revealed a stable interaction, indicated by the presence of focal cell adhesion formation. These results together with positive mineralization assays showed the nano group to be an excellent scaffold for bone-implant integration.
ABSTRACT
PURPOSE: This study measured the maximum angulation between 2 implants allowed by the internal walls of the component in screw-retained multiple prostheses using rotational abutment-type components. MATERIALS AND METHODS: Thirty specimens of 3 different brands (Conexão; Neodent; and SIN), consisting of titanium rotational abutments connected to external hexagon abutment analogs with standard platforms, were divided into 3 groups. The specimens were internally filled with polyester resin, screw retained, torque, and sectioned to assess the space existing between the internal wall of the rotational abutment component, edge, and vertex of the hexagon. The measurements were performed using 3-dimensional equipment. RESULTS: When the implant hexagons were oriented edge-to-edge, groups 1, 2, and 3 presented 40.75, 45.00, and 31.89 degrees, respectively. Vertex-to-vertex hexagon orientation showed 9.79, 18.18, and 3.27 degrees for groups 1, 2, and 3, respectively. CONCLUSIONS: The maximum mean angulation in the mesio/distal direction between the 2 implants with hexagon-oriented vertex-to-vertex is 10.41 degrees, and hexagon-oriented edge-to-edge is 39.54 degrees. This study suggests guidelines for positioning external hexagon implants for interference-free screw-retained multiple prostheses using rotational abutment-type components.
Subject(s)
Bone Screws , Dental Abutments , Dental Implants , Guidelines as Topic , HumansABSTRACT
The aim of the present review is to discuss two forms of treatment for myofascial pain: laser therapy and dry needling. Although studies have reported the deactivation of myofascial trigger points with these two methods, clinical trials demonstrating their efficacy are scarce. The literature reports greater efficacy with the use of laser over dry needling. It has been suggested that improvements in microcirculation through the administration of laser therapy may favor the supply of oxygen to the cells under conditions of hypoxia and help remove the waste products of cell metabolism, thereby breaking the vicious cycle of pain, muscle spasm and further pain. While laser therapy is the method of choice for patients with a fear of needles and healthcare professionals inexperienced with the dry needling technique, further controlled studies are still needed to prove the greater efficacy of this method.