The primary teeth consist of 20 teeth {4 incisors, 2 canines and 4 molars in each arch}. The eruption sequence in the primary dentition usually follows a definite pattern. Central incisors erupt first, followed by lateral incisors, first molars, canines and 2nd molars.

The upper (maxillary) central incisors erupt at 6 months of age, then the lower (mandibular) lateral incisors at 7-8 months, then the upper lateral incisors at 8-9 months. At about 1 year, the first primary molars appear, followed by primary canines at 16 months. 2nd primary molars erupt at 2 years.

There may be a little variation in the time of eruption of these teeth ; it usually doesn't signify any abnormality in the eruption.

At around 6 years of age, the child's lower first permanent molars erupt. Along with it, the permanent central incisors may also come in.

Variations from these factors coupled with discrepancies in tooth and jaw size and also heredity may be factors in producing certain types of malocclusion.

Is when teeth do not erupt in the normal position causing unsightly appearance, crowding of teeth & food entrapment (preventing proper cleaning). It is usually caused by discrepancies in the jaws & tooth size, heredity, variations from the usual eruption sequence & finally habits like thumb sucking & mouth-breathing.

Malocclusions may be broadly classified into 2 categories:

• Dental (because of teeth erupting unfavourably)
• Skeletal (because of deformity of the bone - this may need to be corrected surgically.)