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The extracted teeth which were treated with the surface-active como-nomer NPG-CGE after been etched in phosphoric acid were adheredtogether with "EB" type Ⅰ composite material. The adhesive proper-ties of the specimens were tested by tensile bond strength. The test results showed, without tooth surface treatment the tensilebond strength was poor .However, the adhesive properties were significantlyincreased in enamel specimens when they were etched first in phosphoricacid. But, when dentin was similarly... The extracted teeth which were treated with the surface-active como-nomer NPG-CGE after been etched in phosphoric acid were adheredtogether with "EB" type Ⅰ composite material. The adhesive proper-ties of the specimens were tested by tensile bond strength. The test results showed, without tooth surface treatment the tensilebond strength was poor .However, the adhesive properties were significantlyincreased in enamel specimens when they were etched first in phosphoricacid. But, when dentin was similarly treated the result was poor. WhenNPG-CGE was used after etching, the best tensile bond strength wasobtained in both enamel and dentin. After soaking the specimens in water for 100 days the tensile bondstrength of the NPG-GGE treated teeth was apparently unaffected. But,NPG-CGE stored in ethaaol for 2 months began to lose its strength. 用抗张强度实验测定了经偶联剂NPG-CGE与磷酸处理的离体人牙对复合充填树脂的粘结强度。结果表明,牙面经磷酸处理再加用偶联剂的粘结性优于单用磷酸处理,以牙本质的粘结强度增高最明显。进行了粘结耐水实验和偶联剂贮存有效期实验。并对结果作初步讨论。 The biological compatibility of dental materials have not been extensively tested in our country. There are no unified national standards for such materials. We have done some experiments to assess the biological compatibilities of the polycarboxylic compound ceramic which we developed and intended to use in the clinic.In reference to the American National Standards/ADA Documents No. 41, we have completed: 1) short term systemic toxicity tests: oral route; 2) acute systemic toxicity tests: intraperitoneal injection;... The biological compatibility of dental materials have not been extensively tested in our country. There are no unified national standards for such materials. We have done some experiments to assess the biological compatibilities of the polycarboxylic compound ceramic which we developed and intended to use in the clinic.In reference to the American National Standards/ADA Documents No. 41, we have completed: 1) short term systemic toxicity tests: oral route; 2) acute systemic toxicity tests: intraperitoneal injection; 3)subacute systemic toxicity tests: oral route; 4) haemolysis tests (in vitro tests directly onmaterial; 5) in vitro cytotoxicity tests; 6) the Ames m.utagenicity tests; 7) short term intramuscular implant tests;8) pyrogen tests(both limulus tests and rabbit tests; 9) intracutaneous injection tests; 10) pulp and dentin response tests.The results of the above tests revealed that the polycarboxylic compound ceramic, had no toxicity, no haemolytic activities, no cytotoxicitY in vitro, no mutagenic activities, no irritation to muscle or skin.Pulp and dentin tests were made to assess the-response of the dental pulp and dentin to the compound material. After 7, 45 and 90 days, the tested teeth were examined under microscope. The results were compared with that of silicate cement and that of zinc oxide and eugenol paste. We found that the response of the pulp and dentin to the compound ceramic were similar to that of zinc oxide and eugenol paste. In some respects, the response were even milder than that of Zinc oxide eugenol paste. The compound ceramic did no harm to pulp and dentin. We concluded that the polycarboxylic compound ceramic possessed very good biological compatibilities and can be used in clinic safely. 本文作者参照美国国家标准(ADA41号文件),对自行研制的羧聚复合陶瓷材料的组织相容性进行了实验研究。实验包括1.急性毒性实验;2.亚急性毒性实验;3.溶血试验;4.皮内试验;5.短期肌肉内植入试验;6.热原试验;7.抑茵试验;8.细胞毒性试验;9.Ames试验;10.摸拟动物牙髓刺激试验。实验结果表明,该材料具有良好的生物相容性,安全无毒,无溶血性、无致突变性,对肌肉组织刺激轻微,对皮肤无刺激,不含热原物质。对牙髓和牙本质的刺激与氧化锌丁香油糊剂所引起的相似,可用于临床。 Fluoride injections were given in the rat with 0.25% sodium fluoride solution at the doses of 1-6 ml/kg body wt. The chronic fluorosis enamel appeared after 16-30 days. Acute fluorosis showed at the doses of 6 ml/kg body wt. In the chronic fluorosis, there were the lines in yellow alternating with white colour on the surface of incisors. Under the optical microscope, the dark zone in the enamel or dentin on the longitudinal sections were found. In the soft X-ray examination, the zone were radiolucent,... Fluoride injections were given in the rat with 0.25% sodium fluoride solution at the doses of 1-6 ml/kg body wt. The chronic fluorosis enamel appeared after 16-30 days. Acute fluorosis showed at the doses of 6 ml/kg body wt. In the chronic fluorosis, there were the lines in yellow alternating with white colour on the surface of incisors. Under the optical microscope, the dark zone in the enamel or dentin on the longitudinal sections were found. In the soft X-ray examination, the zone were radiolucent, and under the polarizing microscope, they were positive birefringence. Meantime, such changes decribed above were also found in dentin. Besides the incisor, there was abnormal calcification in alveoli and epiphysis of femur. The seriousness of chronic fluorosis depends on the doses, kinds, of fluorides, and the age of rats. 大鼠注射0.25%氟化钠溶液1~6毫升/千克体重持续到16~30天时,产生典型的慢性氟中毒。大于此剂量时,皆有急性氟中毒发生。慢性氟中毒时,大鼠切牙出现黄白相间的斑釉条纹;纵断磨片在光学显微镜下有釉质暗带;软X线检查,暗带有透射现象;偏光显微镜检查此暗带呈正光性双折射。牙本质也有相应改变。除牙齿外,牙槽骨和股骨也有钙化紊乱现象。慢性氟中毒的程度与氟化物的种类、剂量以及动物的年龄、进入体内的钙离子等因素有关。
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