'This survey covers 4 years and 5042 teeth of 3500 consecutive endodontic patients were observed to determine the frequency of endodontic treatment. Firstly; patients divided into two groups according to their gender and then each group divided into seven sub groups which are 10-19, 20-29, 30-39, 40-49, 50- 59, 60-69 and 70-79. First molar teeth were most frequently needed for endodontic treatment in the female 10-19 age group (45.65%). In the female group demanding endodontic treatment of incisors increased by the age. First molar teeth (41.03%) and upper first molar teeth (27.36%) were most frequently needed endodontic treatment in the male 10-19 age group. In the male group seeking endodontic treatment of bicuspids also increased by the age.'