Determination of the compressive modulus of elasticity of periodontal ligament derived from human first premolars oleh Nuttapol Limjeerajarus, Pimpet Sratong-on, Phetcharat Dhammayannarangsi, Kevin A. Tompkins, Paksinee Kamolratanakul, Krisadi Phannarus, Thanaphum Osathanon, Chalida Nakalekha Limjeerajarus