Third molars emergence status among 15 to 16 year-old Tanzanian youths.

Background: Adequate knowledge of timing and pattern of the third molars is essential. The molars are often used to supplement human maturity indicators for school attendance, social benefits, employment, and marriage, differentiating the juvenile from the adult's status in criminal law cases, unidentified cadavers and human remains when birth records are not adequate or not available. BROAD OBJECTIVE: The study was carried out to investigate the emergence status of the third molar tooth among 15 to 16 year-old Tanzanian adolescents.

Methodology: A cross-sectional community based study was carried out among secondary school children in Ilala District, Dar es Salaam, Tanzania. This study included 203 adolescents aged 15-16 years old of whom 54% were boys and 46% girls. It was a subsample of randomly selected Tanzanian youths who were part of a larger sample of 869 children from randomly selected 16 schools from different parts of the district covering the whole range of socio-economic background.

Results: More third molars were already in occlusion in girls (11-13%) than in boys (3-4%) while girls had more third molars emerged into the oral cavity than boys did. The girls had about 15% to 20% of the four third molar teeth emerged in the oral cavity compared to about 3% to 18% in boys. Except for the mandibular right third molar, all the differences in emergence of the third molars between girls and boys were statistically significant. More mandibular third molars had emerged than the corresponding maxillary ones.

Discussion and conclusions: Third molars were in occlusion in 3-13% of the Tanzanian youths aged 15-16 years indicating earlier emergence than in Caucasian populations. Hence, the need for specific third molars emergence standard tables molars is evident. More studies both cross sectional and longitudinal type involving a larger sample to provide the median and mean ages, rate and pattern of emergence of the third molars in the Tanzanian youth populations are recommended.