Abstract：
OBJECTIVE: To assess the biocompatibility of platinum silicone elastomer A-2000 used in combined maxillofacial defects prosthesis, after being deteriorated by an accelerated aging process resembling both the extra and intraoral environment. This assessment was done indirectly on human-derived dermal and gingival tissues.
METHODS: One hundred eight samples of room-temperature vulcanized A-2000 platinum silicone were equally divided into extrinsically pigmented and non-pigmented groups to replicate combined maxillofacial defects. Accelerated aging was applied to pigmented samples to mimic extra- and intra-oral conditions, while non-aged counterparts served as controls. After isolating human cell lineages, dermal and gingival fibroblasts were indirectly exposed to silicone sample media. Cytotoxicity to cultured fibroblasts was assessed via MTT assay. Statistical significance was determined by repeated measures of one-way ANOVA (p < 0.01), evaluating cytotoxicity on dermal and gingival fibroblasts.
RESULTS: MTT assay showed increased cytotoxicity in pigmented silicon samples subjected to extraoral aging compared to non-aged counterparts (p < 0.01). Non-pigmented silicon, modeling intraoral conditions, exhibited cytotoxicity after 48 h (p < 0.05). Both aged and non-aged silicon extracts equally sensitized gingival fibroblasts at 72 h (p < 0.001). Negative correlations between pigmented and non-pigmented silicon were observed in dermal cell growth (p > 0.05, except at 24 h, r = 0.2), with accelerated aging showing minimal impact on the pigmentation effect (p > 0.05).
CONCLUSIONS: The retrieved diminished cellular metabolic activity of platinum silicone elastomer was in an acceptable clinical range, pointing out the importance of periodic assessments of the maxillofacial prosthesis for replacement depending on aging and cytotoxic harmful cellular responses.
METHODS: One hundred eight samples of room-temperature vulcanized A-2000 platinum silicone were equally divided into extrinsically pigmented and non-pigmented groups to replicate combined maxillofacial defects. Accelerated aging was applied to pigmented samples to mimic extra- and intra-oral conditions, while non-aged counterparts served as controls. After isolating human cell lineages, dermal and gingival fibroblasts were indirectly exposed to silicone sample media. Cytotoxicity to cultured fibroblasts was assessed via MTT assay. Statistical significance was determined by repeated measures of one-way ANOVA (p < 0.01), evaluating cytotoxicity on dermal and gingival fibroblasts.
RESULTS: MTT assay showed increased cytotoxicity in pigmented silicon samples subjected to extraoral aging compared to non-aged counterparts (p < 0.01). Non-pigmented silicon, modeling intraoral conditions, exhibited cytotoxicity after 48 h (p < 0.05). Both aged and non-aged silicon extracts equally sensitized gingival fibroblasts at 72 h (p < 0.001). Negative correlations between pigmented and non-pigmented silicon were observed in dermal cell growth (p > 0.05, except at 24 h, r = 0.2), with accelerated aging showing minimal impact on the pigmentation effect (p > 0.05).
CONCLUSIONS: The retrieved diminished cellular metabolic activity of platinum silicone elastomer was in an acceptable clinical range, pointing out the importance of periodic assessments of the maxillofacial prosthesis for replacement depending on aging and cytotoxic harmful cellular responses.
摘要：
目的：评估铂硅弹性体A-2000在颌面部联合缺损假体中的生物相容性，在因类似于口内外环境的加速老化过程而恶化后。该评估是在人源皮肤和牙龈组织上间接进行的。
方法：将108个室温硫化的A-2000铂硅胶样品平均分为外色素组和无色素组，以复制合并的颌面部缺损。加速老化应用于色素沉着样品以模拟口腔外和口腔内条件，而非老年人作为对照。在分离出人类细胞谱系后,真皮和牙龈成纤维细胞间接暴露于硅胶样品培养基中.通过MTT测定评估对培养的成纤维细胞的细胞毒性。通过单因素方差分析的重复测量确定统计学显著性(p<0.01),评估对真皮和牙龈成纤维细胞的细胞毒性。
结果:MTT测定显示,与未老化的对应物相比,经受口外老化的着色硅样品的细胞毒性增加(p<0.01)。非着色硅，口内条件建模，48小时后表现出细胞毒性（p<0.05）。老化和未老化的硅提取物在72小时时同样致敏牙龈成纤维细胞(p<0.001)。在真皮细胞生长中观察到色素和非色素硅之间的负相关（p>0.05，除了在24h，r=0.2),加速老化对色素沉着影响最小(p>0.05)。
结论：检索到的铂硅氧烷弹性体的细胞代谢活性降低在可接受的临床范围内，指出根据老化和细胞毒性有害细胞反应定期评估颌面假体置换的重要性。
方法：将108个室温硫化的A-2000铂硅胶样品平均分为外色素组和无色素组，以复制合并的颌面部缺损。加速老化应用于色素沉着样品以模拟口腔外和口腔内条件，而非老年人作为对照。在分离出人类细胞谱系后,真皮和牙龈成纤维细胞间接暴露于硅胶样品培养基中.通过MTT测定评估对培养的成纤维细胞的细胞毒性。通过单因素方差分析的重复测量确定统计学显著性(p<0.01),评估对真皮和牙龈成纤维细胞的细胞毒性。
结果:MTT测定显示,与未老化的对应物相比,经受口外老化的着色硅样品的细胞毒性增加(p<0.01)。非着色硅，口内条件建模，48小时后表现出细胞毒性（p<0.05）。老化和未老化的硅提取物在72小时时同样致敏牙龈成纤维细胞(p<0.001)。在真皮细胞生长中观察到色素和非色素硅之间的负相关（p>0.05，除了在24h，r=0.2),加速老化对色素沉着影响最小(p>0.05)。
结论：检索到的铂硅氧烷弹性体的细胞代谢活性降低在可接受的临床范围内，指出根据老化和细胞毒性有害细胞反应定期评估颌面假体置换的重要性。
