Development of antimicrobial denture base resin with antibacterial denatured apatites

在以老年人为主的社会中，义齿菌斑的控制是一个重要的问题。因此，为开发抗菌义齿基托树脂，制备了添加两种磷灰石基抗菌剂的实验树脂，并对其抗菌效果进行了研究。采用硅酸盐磷灰石(Si-HAP：UBe材料)和银烧结型磷灰石(Ag-HAP：Sangi)作为抗菌剂，考察了抗菌剂的添加对实验树脂物理性能的影响。将其添加到市售义齿基托树脂(Acron Clear：GC)中，质量分数为3~5%。在水中老化0~6个月后，对白念珠菌的抗菌效果、弯曲强度和颜色稳定性进行了检测。所有实验树脂在水中浸泡6个月后仍保持抗菌效果，但含银羟基磷灰石的树脂的抗菌效果高于含硅羟基磷灰石的树脂。与未添加树脂相比，实验树脂的弯曲强度降低了约5~10%，但弹性模量和弯曲挠度与未添加树脂的相比无显著差异。在水中浸泡6个月后，实验树脂的弯曲性能没有明显下降。实验树脂在水中6个月与浸泡前的色差(ΔE^*ab)，含银羟基磷灰石的树脂约为2 5，含硅羟基磷灰石的树脂约为4 3。这些值可以忽略不计，因为透明树脂被用作基础树脂。实验结果表明，实验用树脂可用于临床。

The denture plaque control is an important problem in a society composed largely of elderly people. Therefore, to develop antimicrobial denture base resins, the experimental resins in which were added two apatite-based antibacterial agents were prepared and their antimicrobaial effects were investigated. The influences of addition of antibacterial agents on the physical properties of experimental resins were also examined.A silicate-containing apatite (Si-HAp : Ube Materials) and a silver-sintering apatite (Ag-HAp : Sangi) were used as antibacterial agent. These were added in a commercial denture base resin (Acron Clear : GC) in the range of 3 〜 5 mass%. The durability of antimicobial effects to Candida albicans, flexural strength and color stability of them were examined with aging in water from 0 to 6 months.The antimicrobial effects of experimental resins were maintained in all experimental groups even at 6 months after immersion in water, although its effect was higher for the resin with Ag-HAp than for the resin with Si-HAp. The flexural strengths of experimental resins decreased about 5〜10 % as compared with that of non-added resin, but there was no significant difference in the elastic modulus and flexural deflection between experimental resins and non-added resin. These flexural properties of experimental resins did not decrease significantly after 6 months in water. The color difference (ΔE^*ab) of experimental resin after 6 months in water to before immersion was about 2.5 for the resins with Ag-HAp and about 4.3 for the resins with Si-HAp. These values were negligible because transparent resin was used as the base resin. From these results, it was suggested that the experimental resins could use in clinical application.