Table 3

Distribution of occlusal traits and malocclusion requiring treatment by education level of mother

All (n=557, 100%)Education level of mother
 (n=105, 19%)(n=243, 44%)(n=209, 38%)
N or meanPer cent or SDN or meanPer cent or SDN or meanPer cent or SDN or meanPer cent or SDp for χ2 test
Occlusal traits not used for diagnosis
Dental age
 III B99181615421741200.15
 III C2905266631225010249
 IV A16830232279336632
Midline discrepancy (mm)†
Tooth size of upper left incisor (mm)†
Level of dental caries (sum of decayed, filled teeth for mixed and permanent dentition)†
Occlusal traits used for diagnosis
Increased overjet which needs treatment
 >6 mm2044494730.97
 ≤6 mm53796101962349620297
Reverse overjet which needs treatment
 >1 mm1221152630.54
 ≤1 mm54598104992389820397
Deep bite
 Deep bite causing notable indentations of the palatal gingivae511100420.10
 Deep bite or normal overbite without indentations or signs of trauma552991049924310020598
Open bite which needs treatment
 >4 mm100000110.43
 ≤4 mm556100105100243100208100
Anterior crossbite
Posterior crossbite
Scissor bite
Displacement of teeth in the maxillary arch which needs treatment
 >4 mm70131312281229140.75
 ≤4 mm4878792882158918086
Displacement of teeth in the mandibular arch which needs treatment
 >4 mm20455115420.26
 ≤4 mm53796100952329620598
Cleft lip and/or palate
Hypodontia which needs treatment
Impeded eruption
Partially erupted teeth, tipped and impacted against adjacent teeth
Presence of supernumerary teeth
Molar relationship by Angle Classification
 Class I34963575415062142680.006*
 Class II11320272646194019
 Class III37766135189
 Not applicable58101514341494
Diagnosed malocclusion
 Grade 1397772081260.13
 Grade 211020242350213617
 Grade 321238444294397435
 Grade 418133272677327737
 Grade 51533321105
Malocclusion requiring treatment
  • *p<0.05.

  • †Continuous variables were analysed with analysis of variance (ANOVA).