過去針對縫線對傷口癒合的影響主要在兩方面，一是傷口癒合隨時間的組織變化，用組織染色的方式來判斷癒合的程度，主要是判斷新生組織形成的成分及數量，及細胞的增生的數量。另一方式的測試多在體外用不同的縫線打不同的結，測量其強度，或者採取單一縫法，觀察癒合時間對皮膚抗拉強度的關係。至今，未有研究是針對不同的縫合技術在不同時間的癒合情形的拉伸強度。此計畫的目的是直接對不同縫線技術下的受傷組織在不同的術後時間做力學評估，以力學性質來評估受傷組織是否受縫線縫法影響其傷口之癒合強度。
以大鼠皮膚為實驗對象，在大鼠背上兩側製造2cm的傷口，使用4/0缝線，分別為皮上(4n)、皮下(4v)、皮上皮下(4n4v)以3種縫法縫合，經1、2、4及6週癒合時間後，計算其抗拉強度、應變場及彈性係數以及組織染色。
實驗結果發現，對於癒合2週之傷口，4n傷口之癒合程度小於4v及4n4v(p=0.028)，但到6週時，4n以及4v傷口已大於4n4v(p=0.017、0.012)，4n4v抗拉強度變差的原因可能是Vicryl縫線的『降解時間』、『應力遮蔽效應』以及『缝針對皮膚破壞的程度』所造成，此資訊對缝線技術的改善將是很大的幫助。另外研究發現近頭部之鼠皮厚度，較近尾部厚，這在過去文獻裡還未有人提及，未來可供設計實驗參數之參考。

In the past wound healing studies were focused on the histological analyses. Histological stains for sliced tissues were used to analyze the progress of healing. The other studies related on suture technologies were focused on mechanical strengths of different suture method in vitro without real living tissues. We hypothesize the suture strength and tying method should play an important role in the progress of healing. So far, no similar studies had been investigated. The purpose of this study is to investigate the effect of mechanical property respect to different suture patterns in wounded skin.
This study tries to analyze the temporal wound healing strength after skin injury. Three suture technologies were used to investigate their effects of the strength of healing tissues. Rat skins will be used in this project. First, rat was made 3 2-cm long cuts on the back and sutured with 3 different patterns (4n, 4v, 4n4v). In 1, 2, 4, and 6 weeks, a 3 x 5 cm skin along the injured sites was harvested for mechanical testing and histological staining. A soft tissue MTS with special skin grip was used to test the strength of the healing skins. Hematoxylin and Eosin staining and Masson Trichrome staining were used to observe the healing tissue and cell numbers along the healing injury sites.
The results show that 4n-sutured skin had worse recovery than 4v and 4n4v(p=0.028) in 2 weeks wound skin. But 4n and 4v-sutured had better recovery than 4n4v in 6 weeks. We think that different healing courses for 4n, 4v, 4n4v suture patterns may result from the degradation of Vicryl suture, stress shielding effect, and the degree of skin destruction. This information was helpful for suture technique improvement. We also find the dorsum skin near head was thicker than that near tail. This finding was first time, and it can be used as important reference for designing experimental parameter in the future.

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