J Oral Maxillofac Surg 69:1291-1294, 2011 Malondialdehyde Levels in Dental Follicles of Asymptomatic Impacted Third Molars Umut Tekin, DDS, PhD,* U ¨ çler Kısa, PhD,† Orhan Güven, DDS, PhD,‡ and Hüseyin Kurku, MD§ Purpose: Increased levels of reactive oxygen species lead to oxidative stress and tissue damage. Malondialdehyde (MDA) is one of many low-molecular-weight endproducts of lipid peroxidation that increases with oxidative stress. The aim of this study was to determine oxidative stress in dental follicles (DFs) of radiologically asymptomatic impacted third molars (ITMs) using MDA. Materials and Methods: This study involved 40 DFs of 40 patients referred for clinically and radio- graphically asymptomatic ITMs. Forty healthy gingival tissues in the same patients were obtained during surgical removal of teeth as a control group. DF widths on periapical radiographs narrower than 2.5 mm were included in the study. All tissues samples were analyzed for MDA as an indicator of oxidative stress. Results: Levels of MDA were significantly higher in DFs from ITMs than those from healthy gingival tissues of the same patients (P  .01). Conclusion: The results suggest that significant oxidative stress may occur in DFs of asymptomatic ITMs. The findings suggest that increased MDA may play an important role in oxidative stress in DFs. In light of these preliminary findings of the present study, further investigations and comprehensive studies are required to determine the role of antioxidants that scavenge free radicals in DFs. © 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:1291-1294, 2011 The surgical removal of impacted third molars (ITMs) is the most frequent operation in oral surgery. How- ever, there is still no general agreement about the need for surgical removal of asymptomatic ITMs. 1-4 Despite recommendations of a National Institutes of Health Consensus Development Conference on the removal of ITMs, 5 no clear agreement has been reached on the prophylactic removal of asymptom- atic ITMs. 6,7 Previous studies have supported the derivation of epithelial tumors and odontogenic cysts from epithe- lial cells in oral tissues, such as remnants of odonto- genic epithelium found in the dental follicle (DF) of an ITM and the surface epithelial lining of the oral mucosa. 4 It is accepted that pericoronal radiolucency narrower than 2.5 mm in follicular width is nonpatho- logic in DFs of asymptomatic ITMs. 8 Reactive oxygen species (ROS) consist of a variety of molecules and free radicals (chemical species with one unpaired electron) derived from molecular oxy- gen. Increased levels of ROS lead to oxidative stress and damage to critical biomolecules, resulting in del- eterious biological effects. Cells have developed sev- eral antioxidant defense mechanisms to neutralize these harmful ROS. 9-11 However, if the scavenging capacity of affected tissues is exceeded by an over- whelming production of free radicals, significant tis- sue damage can occur. ROS induce lipid peroxidation (LPO). When ROS interact with polyunsaturated fatty acids in mem- branes or lipoproteins, the process of LPO begins. In the resulting LPO, fatty acids are transformed to the primary product of lipid peroxides. 12 Uncontrolled production of lipid peroxides can cause oxidative stress, with significant damage to cell integrity. 12,13 *Associate Professor, Department of Oral and Maxillofacial Sur- gery, Faculty of Dentistry, University of Kırıkkale, Ankara, Turkey. †Associate Professor, Department of Medical Biochemistry, Fac- ulty of Medicine, University of Kırıkkale, Ankara, Turkey. ‡Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Ankara, Ankara, Turkey. §Resident, Department of Medical Biochemistry, Faculty of Med- icine, University of Kırıkkale, Ankara, Turkey. Address correspondence and reprint requests to Dr Tekin: De- partment of Oral and Maxillofacial Surgery, Kirikkale University Faculty of Dentistry, Ozanlar Sokak 6/1, 06600 Ankara, Kurtulus, Turkey; e-mail: umutekin@gmail.com © 2011 American Association of Oral and Maxillofacial Surgeons 0278-2391/11/6905-0017$36.00/0 doi:10.1016/j.joms.2010.07.011 1291