[Frequency and causes of extraction of permanent teeth. A ten-year (1968-1977) clinicostatistical investigation].

The purpose of this clinical investigation was to analyze the frequency and the causes of mortality (loss) of 50493 permanent teeth, extracted, during a ten-year (1968-1977) period, in Clinic Exodontia of Dental School University of Athens, at 27804 population of Greece (13140 males and 14664 females). The following conclusions were drawn from the statistical analysis and the interpretation of the results: The mean value of extracted teeth per person was 1.84 and was lower in females (1.70) from males (1.94). Independently of the sex and the jaws (maxillamandible) the greater percentage (60.69%) of extractions was to posterior teeth. The extracted teeth were more in maxilla (52.42%). The more per cent extracted teeth, independently of the sex, were the maxillary central incisors (9.51%) and lateral maxillary incisors (8.61%) and the lower, the mandibular canines (3.41%). Caries and periodontal diseases were responsible for 80.37% of extracted teeth, independently the sex and the age. Caries was the major cause of extraction until 40 years old (71.03%) and after this age the periodontal disease was the major cause of extraction (51.61%).