Gaining space in dental arches

If the teeth are crowded or extremely protrusive, space is needed to align the teeth. In some ocassions little space can be gained by stripping other teeth (it is done carefully only in enamel level).
Otherwise mostly the space is gained by teeth extractions. Usually 2 premolars are extracted to achieve symmetry (one on each side), because their role in chewing food is less important that the role of molars. In some cases it is necessary to remove teeth from both jaws. When making decision to extract the teeth, orthodontist takes into account:

• how much space is needed
• condition of the teeth (caries, big fillings)
• shape and size of the tooth crown (sometimes tooth crowns can be atypically small or peg-shaped)
• position of the tooth (for example, tooth lies in a bad position and it is not possible to achieve the correct position)