Abstract : <p>The reflection and retraction of mucoperiosteal flap is an essential step in most of the surgical procedures. Austin&rsquo;s and Langenbeck&rsquo;s retractors are most commonly used for flap retraction during intraoral surgical procedures. There is no literature on the amount of trauma created to the periosteal layer of the flap by these retractors. Hence, the present study aims at assessing and comparing the extent of trauma created to the periosteal layer of the flap when retracted with Austin&rsquo;s and Langenbeck&rsquo;s retractors during surgical removal of impacted mandibular third molars. The results show that 72% of flaps retracted with Austin&rsquo;s retractor and only 16% of flaps retracted with Langenbeck&rsquo;s retractor exhibited trauma to the periosteal layer as a result of flap retraction. Thus results indicate a significant increase in trauma rate to the periosteal layer of the flap when Austin&rsquo;s retractor is used. Pearson Chi-Square test revealed a significant correlation between duration of the flap retraction and trauma rate in Austin&rsquo;s group (p&lt;0.05), but no such correlation was evident in Langenbeck&rsquo;s group (p=0.466). Austin&rsquo;s retractor causes more trauma to the periosteal layer of the mucoperiosteal flap compared to the Langenbeck&rsquo;s retractor during the flap retraction.</p>