It is very crucial to know the biomechanics of the septal cartilage and adjacent structures during septoplasty. The aim of this study was to investigate the strength changes of different L-strut models after mucoperichondrium elevation, application of septal extension grafts and spreader grafts on an experimental lamb model. Ten lamb heads were dissected according to a dissection protocol and septal resistances were measured with the newton meter at six zones. Three different L-strut types were designed, and all the L-strut models were created at different widths of 15mm, 10mm, and 5mm. In addition, effects of two different types of septal extension grafts and spreader grafts were compared. After mucoperichondrium elevation and harvesting the septum cartilage, there was a significant decrease in the septum resistance (p <0.05). As the width of the L-strut decreased, the septum strength decreased significantly (p <0.05). There was no significant difference between three chondrotomy types at different widths (p >0.05). There was no significant difference between the overlapping SEG and end-to-end SEG in terms of septum resistance (p >0.05). This was the first study to measure septal resistance in lamb heads. The mucoperichondrium and L-strut width were important structures for maintaining septal resistance. Chondrotomy style was not crucial, but as the width of the L-strut increased, the septal resistance increased. The septal extension grafts regardless of suturing style and the spreader grafts added strength to the caudal septum.