The aim of this study was to analyze and compare complications and side effects after removal of 150 mandibular impacted third molar teeth in three age groups. One hundred and fifty patients (65 male and 86 female) had impacted mandibular third molar teeth were enrolled in this study at the Oral and Maxillofacial Surgery Department of the Faculty of Oral and Dental Medicine Cairo University between September 2013 and September 2014. The patients were divided into three age groups: Group A (n = 50): 9-16 years, Group B (n = 50): 17-24 years and Group C (n = 50): older than 24 years. Group A was subjected to germectomy while the Group B and C were subjected to delayed surgical extraction. The difficulty index in studied patients reveals 36.6 were minimally difficult for Group A, 58.7% of procedures were moderately difficult for Group B while 4.7% were very difficult for Group C. Extraction of impacted third molar before the age of 24 year is accompanied with the least incidence and severity of complications.