Table 1 Prevalence of each type of malocclusion in preschool children aged 3–6 years
3 years old | 4 years old | 5 years old | 6 years old | Total | |
|---|---|---|---|---|---|
(n = 119) | (n = 171) | (n = 146) | (n = 67) | (n = 503) | |
Sagittal malocclusion | 42.0% | 33.3% | 37.7% | 38.8% | 37.4% |
Anterior crossbite (AC) | 11.8% | 7.0% | 10.9% | 9.0% | 9.5% |
(mild/moderate) | (3.4%/8.4%) | (1.8%/5.3%) | (3.4%/7.5%) | (1.5%/7.5%) | (2.6%/7.0%) |
Excessive Overjet (E) | 30.3% | 26.3% | 26.7% | 29.9% | 27.8% |
Vertical malocclusion | 29.4% | 33.3% | 26.0% | 32.8% | 30.2% |
Deep overbite (D) | 23.5% | 26.3% | 18.5% | 23.9% | 23.1% |
Anterior open bite (AO) | 5.9% | 7.0% | 7.5% | 9.0% | 7.2% |
Transversal malocclusion | 0% | 0% | 0% | 0% | 0% |
Posterior crossbite | 0% | 0% | 0% | 0% | 0% |
Scissors bite | 0% | 0% | 0% | 0% | 0% |
Space discrepancies | 16.0% | 7.6% | 12.3% | 11.9% | 11.5% |
Crowding (C) | 16.0% | 7.6% | 12.3% | 11.9% | 11.5%** |
Multiple types of malocclusion | 20.2% | 15.8% | 16.4% | 16.4% | 17.2% |
Total | 67.2% | 58.5% | 59.6% | 67.2% | 62.0% |