Strain Distribution and Amount of Force Required During Pterygomaxillary Dysjunction: A Comparison of Pterygoid Versus Shark-fin Osteotome.

Objective: This study was conducted to compare the efficacy of Obwegeser's pterygoid osteotome and Laster shark-fin osteotome by measurement of strain adjacent to the pterygomaxillary suture and the amount of force required for dysjunction.

Materials and Methods: Two popular instruments Obwegesser's pterygoid and shark-fin osteotome were tested on dry human skulls. The external force required for separation of the pterygomaxillary suture with these osteotomes was generated by an electronically controlled 'Instron' tester Bi-06-108. Tests were performed with pterygoid osteotome placed on one randomly chosen side and shark-fin osteotome on the other side of the same specimen. The amount of strain developed by each of these instruments was recorded using two strain gauges on the right and left lateral pterygoid plates.

Results: [Table: see text].

Conclusion: Based on the distribution of strain, from this study, we conclude that Laster shark-fin osteotome is efficacious over Obwegeser's Pterygoid osteotome, in Le fort I osteotomy.