RESUMEN
PURPOSE: To compare the accuracy of implant placement between modified and traditional immediate implant placement in mandibular molar regions. METHODS: Twenty-four patients were selected for immediate implantation in the molar area including 24 implantation sites. Preoperative cone-beam CT(CBCT) was conducted and then digital software Simplant 18.0 was used to design the ideal three-dimensional position of the implants. In the experimental group, the implant socket was prepared first according to reference of the remaining natural teeth, then the implant was implanted after minimally invasive extraction. Twelve patients in the control group underwent immediate implantation by traditional immediate implant procedures. Minimally invasive extraction, then socket preparation, and final implanting were performed. All patients underwent CBCT after surgery. Implant sites designed prior to surgery and actual implant sites differences between modified and traditional immediate implant placement were measured by Simplant 18.0 and compared with SPSS 17.0 software package. RESULTS: In the experimental group and control group, the measured average deviation were as follows, the angle was (4.492±0.912)° and (7.255±1.307)°, respectively; The horizontal error of the implant shoulder was (0.379±0.083) mm and (1.229±0.270) mm, respectively; The measuring horizontal error of the implant apex was (1.263±0.267) mm and (2.183±0.264) mm, respectively; The calculative horizontal error of the implant apex was (1.324±0.203) mm and (2.709±0.383) mm, respectively; Depth error of the implant apex was (0.663±0.123) mm and (1.533±0.155) mm, respectively, which were significantly lower than those of the control group. CONCLUSIONS: Compared with the traditional method, modified immediate implantation can improve the accuracy of implantation in mandibular molars.
Asunto(s)
Implantes Dentales , Boca Edéntula , Cirugía Asistida por Computador , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Humanos , Diente Molar/diagnóstico por imagenRESUMEN
Inflammation occurs when the material is implanted into the body. As one of the important immune cells in the regulation of inflammation, macrophages are able to remove pathogens and necrotic cells, and polarize to different phenotypes to regulate inflammatory response for tissue regeneration. Therefore, it is known that the sequential release of immunomodulatory cytokines from the surface of titanium (Ti) implants can regulate the polarization of macrophages and promote osseointegration of implants. In order to control the switch of macrophage phenotypes at desired time, we fabricated hydroxyapatite (HAp) nanotube arrays coating on Ti surface, by acid-etching, alkali-heating and HAp coating sequentially. Then we loaded the interleukin-4 (IL-4) encapsulated by poly (lactic-co-glycolic acid) (PLGA) on the bottom of the nanotube and the interferon-γ (IFN-γ) encapsulated by sodium hyaluronate (SH) on the top of the nanotube. Based on the physical and chemical properties of PLGA and SH and the spatial distribution of loaded cytokines, we hypothesized that the programmed release of IFN-γ and IL-4, which made the phenotypic transition of macrophages at a specific time, so as to regulate inflammation and promote osteogenic repair. Our hypothesis created a new type of drug sustained release system, which has high research value for improving the osseointegration of implants.
Asunto(s)
Durapatita , Titanio , Citocinas , Activación de Macrófagos , Macrófagos , Propiedades de SuperficieRESUMEN
PURPOSE: To compare the mechanical properties of 3D-printed titanium meshes and pre-shaped titanium meshes, and to evaluate the effects of 3D-printed titanium meshes on cell proliferation and differentiation. METHODS: 3D- printed titanium meshes were produced and prepared with laser printing machine. The mechanical properties were analyzed by static tension and compression load test. Bone marrow mesenchymal stem cells (BMSCs) were extracted from 4-week-old male SD rats. BMSCs were co-cultured with 3D-printed titanium meshes of different apertures. Cell counting kit-8 (CCK-8) assay was used to detect cell proliferation. Alkaline phosphatase (ALP) activity assay was used to test ALP activity. The expression of related osteogenic genes was tested by real-time PCR. The adhesion and growth of BMSCs were investigated by scanning electron microscopy (SEM) and living / dead cell staining. SPSS 22.0 software package was used for statistical analysis of the results. RESULTS: The results of 3D-printing Ti-meshes tension and compression loading experiment were excellent. The 3D-printing Ti-meshes showed no inhibitory effects on cell proliferation, survival and adhesion, but had a positive effect on osteogenesis of BMSCs. CONCLUSIONS: The mechanical properties of 3D-printed Ti-meshes are excellent. The 3D-printed Ti-meshes have good biocompatibility.