Journal of Maxillofacial and Oral Surgery

, Volume 17, Issue 2, pp 207–210 | Cite as

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

  • Shoaib Parkar
  • Mueedul IslamEmail author
  • Ramakrishna Tangaturi
  • Hari Keerthy Panthala
  • Azhar Khan
  • Mohammed Imran
  • Jayesh Anand
Comparative Study



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.


Instrument used

Mean force to achieve dysjunction

Mean strain developed

Pterygoid osteotome

169 N

887.66 microstrain

Shark-fin osteotome

175.5 N

677.33 microstrain


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.


Le Fort I type osteotomy Obwegeser’s pterygoid osteotome Laster shark-fin osteotome Strain 


Compliance with Ethical Standards

Ethical Approval

This article does not contain any studies with human participants or animals performed by any of the authors. Ethical committee clearance was taken from the college ethical committee.


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Copyright information

© The Association of Oral and Maxillofacial Surgeons of India 2017

Authors and Affiliations

  • Shoaib Parkar
    • 1
  • Mueedul Islam
    • 1
    Email author
  • Ramakrishna Tangaturi
    • 1
  • Hari Keerthy Panthala
    • 1
  • Azhar Khan
    • 1
  • Mohammed Imran
    • 1
  • Jayesh Anand
    • 1
  1. 1.The Oxford Dental CollegeBangaloreIndia

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