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Updated: Jul 19, 2026

Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Prevalence of malocclusion among 12-15-year-olds in Moshi, Tanzania, using Bjork's criteria
D S Rwakatema1, P M Nganga, A M Kemoli
1Department of Dentistry, Kilimanjaro Christian Medical College, Tumaini University, P.O. Box 3010, Moshi, Tanzania.
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.
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