可注射式聚電解質錯合體水膠於軟組織填充之應用研究

Development of Injectable Polyelectrolyte Complex Hydrogel for Soft Tissue Augmentation

紀典佑(Dian-Yu Ji)

指導教授 ： 李勝揚

共同指導教授 ： 楊正昌

臺北醫學大學/口腔醫學院/牙醫學系碩博士班/博士(2012年)

https://doi.org/10.6831/TMU.2012.00020

摘要

本研究目的在於開發聚電解質錯合體水膠 (polyelectrolyte complex hydrogel, PEC)，並結合氫氧基磷灰石 (hydroxyapatite, HAp)球體與人類牙髓幹細胞 (dental pulp stem cells, DPSCs)，製備成可注射式軟組織填補物 (soft tissue augmentation)，並以動物模型評估其於軟組織的效果維持與膠原蛋白再生能力。
利用帶正電的幾丁聚醣 (chitosan, CS)與帶負電的γ-聚麩胺酸 (γ-polyglutamic acid, γ-PGA)形成聚電解質錯合體水膠，其凝膠率高達35%與平衡吸水率低至1043%，且具有優異的機械強度與長降解時間特性，進一步在NIH3T3與DPSCs的細胞試驗中，證實具有良好的生物相容性。
聚電解質錯合體水膠載體，結合氫氧基磷灰石球體填補物於系統中，以噴霧乾燥法造粒，在產率穩定及持續生產的加工前提下，以適當的進料濃度與接著劑濃度配比，製作出產物含73%的25-45 μm之HAp球體。利用高溫燒結加工後，可得表面孔洞小，且平整細緻的球體。與HAp球體混合後，具有低注射力的特性，且長時間浸至於PBS水溶液中，仍可維持良好的結構完整性。
本研究藉由蘭嶼豬的耳朵皮下模型，評估材料的維持時間與膠原蛋白生成效益。在植入分別含有HAp之羧甲基纖維素 (carboxymethyl cellulose, CMC)與商品RadiesseR的組別中，在第2個月時，樣品的維持高度即會顯著地降低 (p < 0.05)，然而利用PEC水膠系統的組別(PEC及PEC/HAp)，不僅可以維持拱頂狀的形態，在經過2個月前 (2.42 ± 0.50 mm及3.75 ± 0.26 mm)與2個月後 (1.52 ± 0.77 mm及3.24 ± 0.45 mm)，均無顯著的差異，且PEC/HAp中，6個月後僅下降27%。膠原蛋白的觀察發現，在CMC/HAp組別中，由於CMC降解速率過快，膠原蛋白並未能快速生成，反而造成體積壓縮。在PEC水膠系統當中，因降解緩慢，使纖維母細胞有足夠的時間生成，其膠原蛋白較為豐富。加入DPSCs時，不僅可加強PEC水膠的維持高度 (p < 0.05)，更觀察到組織中，膠原蛋白纖維呈現密集的網狀分布。以上結果顯示，PEC水膠載體本身具有軟組織填充能力，添加HAp球體更可提升其維持效果，而加入DPSCs能幫助膠原蛋白的生成。

關鍵字

幾丁聚醣；聚麩胺酸；聚電解質錯合體；氫氧基磷灰石；軟組織填充；牙髓幹細胞

並列摘要

The purpose of this study is to develop a polyelectrolyte complex (PEC) hydrogel combined with spherical hydroxyapatite (HAp) particles and dental pulp stem cells (DPSCs) as the injectable dermal filler for soft tissue augmentation. We also estimated the long-lasting and collagenesis performance by animal model.
The chitosan (CS) / γ-polyglutamic acid (γ-PGA) PEC hydrogel with oppositely charged ionic cross-linking, a high gel content (35%), low equilibrium water uptake (1043%), high mechanical strength, and low degradation rate. Studies using NIH3T3 and DPSCs indicated the PEC hydrogel had satisfactory cell biocompatibility.
In spherical HAp particles process, we control the continuance and production efficiency by spray drying technology. The HAp particles were producted in 25-45 μm of 73% by suitable slurry and binder concentration. The particle surface could be smooth and low porosity by sinter. This PEC/HAp system showed good structural integrity and low injection force.
In an animal study, the materials were implanted within the dorsal dermis of a swine ear to evaluate the retention and collagenesis.The thickness of the CMC/HAp and RadiesseR group dropped rapidly at 2 months (p < 0.05).The dome-like shape of the PEC and PEC/HAp material were similar at 2 months (1.52 ± 0.77 mm and 3.24 ± 0.45 mm) and 1 day (2.42 ± 0.50 mm and 3.75 ± 0.26 mm) and did not statistically differ (p > 0.05). The PEC/HAp group was only 27% lower at 6 months. The rich and thick new collagen was observed in the PEC hydrogel groups compare with the CMC groups. We found the CMC/HAp group showed collagen surrounding the HAp particles, but collagen synthesis was not as fast as the degradation rate of the CMC gel to support the soft tissue. However, the PEC hydrogel groups have large new collagen, because PEC hydrogel has a slow degradation rate.In the PEC/DPSCs group, it has longer lasting (p < 0.05) and large network new collagen compara with PEC group. These results suggest that this PEC hydrogel system combined with HAp or DPSCs can be used as an alternative for soft tissue augmentation.

並列關鍵字

Polyelectrolyte complex ； Chitosan ； γ-polyglutamic acid ； Hydroxyapatite ； Dermal filler ； Soft tissue augmentation ； Dental pulp stem cells

參考文獻

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