A splint includes a thermoplastic body and a thermochromic layer. The thermoplastic body has a softening and operating temperature. The thermochromic layer is disposed on the thermoplastic body. The thermochromic layer has at least one thermochromic pattern region. The thermochromic pattern region has a thermochromic temperature. The thermochromic temperature is lower than the softening and operating temperature but higher than room temperature.一種副木包含熱塑性本體與至少一熱變色圖案層。熱塑性本體具有軟化操作溫度。熱變色圖案層位於熱塑性本體上。熱變色圖案層包含至少一熱變色區域。熱變色區域具有熱變色溫度。熱變色溫度低於該軟化操作溫度,但高於室溫。
