7. Alveolar size
• alveolar size is the primary factors that
determine the status of the permanent dental
arch. If it too large spacing.
8. Physiological spacing
(ugly duckling stage )
• The maxillary central incisors can
also be quite distally inclined when
they first erupt, which produces a
midline diastema between them.
• the maxillary incisor apices being
initially quite close together when
lateral pressure from the erupting
maxillary lateral incisors & canines .