| Objectives:1. The aim of present study was to evaluate the clinical effect of silicone obturator via using the return visit and inspection of clinical obturator prostheses cases;2. To evaluate the application of silicone drainage obturator for treatment on large cystic lesions after fenestration of the jaws. And in order to find a simple, rapid and effective manufacturing methods of silicone drainage obturator on large cystic lesions after fenestration in jaws;3. Observing the different treatment of polymethyl methacrylate (PMMA) influenced on silicon rubber bond strength; finding an easy and effective method enhanced the bond strength between silicone rubber and PMMA, providing theoretical guidance for clinical production of silicone rubber obturator.Methods:1. 5 patients with maxillary silicone over-lining obturator prostheses were studied, and the degree of patients satisfaction and speech intelligibility were examined after 1 month by using the obturator. Analyzed the relationship between the clinical effects and the degree of maxillary defects.2. 4 patients with the silicone drainage obturator after the treatment of fenestration in the jaw cysts. The degree of patients'satisfaction were surveyed and stomo-panorama were examined after 3 months, 6 months and 12 months. Counted the area reduced rate of the cysts on the X-ray to evaluate the effects of silicone drainage obturator.3. 84 PMMA test specimens which met the requirements (10mm×50mm×3mm) were made. The bonding of one side of the specimens (10mm×10mm) were uniform grinding in the same direction and under the same pressure under the running water. Moreover, they were washed by ultrasound, and dried naturally. The specimens were randomly divided into 4 groups:burnished group (control group), sandblasted group, MMA disposed group, sandblasted+MMA disposed group. Each group had 21 specimens, of which 10 specimens were used for shear bond strength (SBS) testing (every test piece was composed of 2 test specimens and sandwich cold curing soft lining silicone rubber). After placed under the free state for 24h, SBS were examined by electronic universal testing machine. One of the specimen was examined by scanning electron microscope.Results:1. There had satisfaction effects of the silicone over-lining obturators in the class II maxillary defects, but poor effects on the cases of class VII maxillary defects.2. It show satisfy clinical effects of silicone drainage obturator after the treatment of fenestration in the jaw cysts.3. The shear bond strength of surface sandblasted group and MMA treatment group were greater than the control group (P<0.05), but they were no statistical meaning between surface sandblasted treatment group and MMA group (P> 0.05); The shear bond strength of surface sandblasted group was significantly greater than the other groups, which had statistical meaning (P＜0.01)4. SEM showed the surface of burnished group (control group) was covered with worn. Sandblasted group was much more rougher, looked like the rock pile; The surface of specimen in the group of MMA treatment and sandblasted+MMA group were filled with microspore, like honeycombed. In addition, the angularity disappeared.Conclusions:1. There had satisfaction effects of the silicone over-lining obturators in the class II maxillary defects.2. But poor effects of the silicone over-lining obturators in the cases of class VII maxillary defects.3. It show satisfy clinical effects of silicone drainage obturator after the treatment of fenestration in the jaw cysts. 4. Surface sandblasted and MMA treatment can both raise the shear bond strength between PMMA and silicone soft liner. But there was no obvious difference between the two treatments.5. In present study, it, after sandblasting+MMA treatment, obtained the maximum shear bond strength between PMMA and silicone soft liner. In addition, it was better than the single treatment and could fully satisfy the needs of clinical use. In order to obtain the better bond strength, we can treat the surface of PMMA obturator with sandblast and MMA before bonding the silicone soft liners. |
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