Prevalence of malocclusion among 12-15-year-olds in Moshi, Tanzania, using Bjork's criteria

OBJECTIVE: To assess the prevalence of malocclusion in 12-15 -year-olds in Moshi, Tanzania. DESIGN: Cross-sectional study. SETTING: Moshi Municipality, Kilimanjaro region, Tanzania. SUBJECTS: Two hundred and eighty nine randomly selected primary school children (153 males and 136 females) had a clinical examination for malocclusion traits done. RESULTS: The overall prevalence of malocclusion was 97.6%. Angle's Class II and III malocclusion occurred in 6.9% and 11% of the sample respectively. Crowding was encountered very frequently in both jaws, especially in the lower anterior segments. Anterior open bite occurred in 6.2% and the deep bite in 10.7% of the sample. There was no significant gender difference in either the overall prevalence of malocclusion or in the occurrence of the different occlusal traits. CONCLUSION: It was noteworthy that some of the malocclusion traits recorded were relatively minor deviations from the normal occlusion. Hence the high prevalence of malocclusion did not necessarily imply a heavy burden of need and demand for orthodontic treatment.