Clear removable aligners are a relatively new way of correcting mild-moderate orthodontic problems following a comprehensive assessment and discussion of the all the available options.
“Invisible” removable aligners are perhaps the highest profile orthodontic appliance, with widespread advertsing in magazines and television. Whilst they have become increasingly sophisticated and refined it remains important to be clear about the circumstances in which these devices are best used and by whom.
It is important to seek an opinion from an orthodontic specialist who will be able to give authoritative advice on the options. 
After any aligner treatment, retainers will be required to ensure the teeth maintain their corrected positions.
What are aligners?
Aligners are thin clear flexible plastic ‘mouthguards’ which fit closely over the teeth. A series of aligners is used to move the teethincrementally according to a treatment plan developed by the orthodontist. Aligner appliances are ideally suited to adult patients whose life-style or work commitments make it difficult for them to wear more visible conventional fixed appliances.
As with any other form of orthodontics, a proper orthodontic assessment, diagnosis and treatment plan is essential to successful aligner treatment. An accurate impression of the mouth is used to create the customised aligners. Each appliance moves the teeth a small distance towards the intended position before moving on to the next in the series until the final result is achieved. Aligners need to be worn full-time, day and night except for meal times. 
When can aligners be used?
Aligners are most commonly used in cases needing alignment of teeth without extractions.
Routine aligner treatments include:
● Mild-moderate dental irregularity
● Crowding which can be corrected with mild-moderate expansion of the dental arch
● Crowding which can be corrected with reductions in tooth width (Inter-proximal reduction or slenderising)
● Mild spacing 
The following cases are examples of when an aligner treatment may require the use of additional techniques such as fixed appliances to achieve an ideal result:
● Severe crowding
● Treatments that require tooth extraction
● Treatments that require complex tooth movements
● Problems that reflect an underlying discrepancy in size or position of the jaws.