RESUMEN
Patients are faced with some complications after third molar extraction. Considering this fact, some techniques are developed to reduce these complications, such as, Chlorhexidine rinse and antibiotic usage. Considering the importance of these complications, this study was conducted for the evaluation of Chlorhexidine rinse and antibiotic usage to reduce post extraction complications of m and ibular third molar in Tehran University Dental School. The study was a r and omized double - blind experimental one. The study cases were assigned to three groups, using Penicillin V [2 gr.], Chlorhexidine rinse using and control group. The opening range of jaw and special distances in the face were measured before surgery, 48 hours and one week later. The statistical tests used were Kruskal - wallis and Mann - whitney U. Penicillin V and Chlorhexidine rinse had no effect on infection, trismus, swelling and dysfunction 7 days after extraction. Chlorhexidine rinse reduced swelling at 48 hours after extraction only, meanwhile the effect of Chlorhexidine rinse and Penicillin V on swelling after 48 hours differed significantly [P<0.01]. The study confirmed the positive effect of Chlorhexidine rinse on removing swelling at 48 hours after extraction of m and ibular third molar, but it had not any effect on other complications. The group using Penicillin V did not show any decrease in post surgical complications