Skip to main content

Table 2 Prevalence of dentition traits in preschool children aged 3–6 years

From: Incompetent lip seal and nail biting as risk factors for malocclusion in Japanese 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)

Mandibular midline deviation

35.3%

43.3%

43.2%

35.8%

40.4%

 right

17.6%

28.7%

25.3%

22.4%

24.3%a

 left

17.6%

14.6%

17.8%

13.4%

16.1%

Unspaced dentitions

40.3%

31.6%

31.5%

26.9%

33.0%b

  1. a: P < 0.01 (Chi-squared test between right and left)
  2. b: P < 0.01 (Chi-squared test between boys and girls) (boys: 26.7%; girls: 39.6%)