Eruption pattern of permanent teeth in Tanzania children and adolescents in Dar es Salaam.

Abstract

The aim of the study was to estimate the mean ages of pennanent teeth eruption in 3-18 years old children and adolescents in Ilala districts, Dar es Salaam. The study included 858 subjects of whom 419 wereboys and 439 girls. The tooth was considered erupted when any part of the tooth crown was visible in the oral vacity. Generally permanent teeth erupted earlier in girls than in boys. The differences were 0.1 - 0.2 years for incisors and first molars, 0.2 - 0.4 years for canines and premolars and 0.3 - 0.5 years for second molars. Except for the second premolars, mandibular teeth erupted earlier than the maxillary in both girls and boys. The difference was about O. 1 - 0.4 years. The order of eruption of the teeth was MI .. 11,. 12, Pm1, c, Pm2, M2 and M3 in the maxillar; and MI, II, 12, c, Pml, Pm2, M2. and M3 in the mandible. The children entered the first and second phases of the mixed dentition at. the ages of 4 and 8 years, respectively. Except for the third molars, all teeth were erupted at the age of 15 years in girls and boys. The results indicate that teeth erupt arlier in girls than boys, and the mandibular erupt earlier than the corresponding macillary teeth. The mean ages of eruption of permanent teeth in children and adolescents in present study were bigger compared to those in previous African studies. However, due to wide variation, of teeth eruption patterns which exist in different tooth pairs, individuals and population groups as reported elsewhere more studies on the subject especially the longitudinal types are justified.