Introduction

Aligners are an alternative to traditional braces and are designed to help guide teeth into their proper position. The aligners are made of a strong plastic material and are fabricated to fit each persons mouth. If a series of aligners are made, each aligner moves the teeth a little bit more into place until the desired movement is completed. Aligners are worn for at least 20 hours a day to reach the desired maximum effectiveness. Each aligners are worn for two to three weeks before changing to the next one. The length of treatment with aligners depends upon the severity of each case.

Aligner Material: 

Aligners are composed of polyurethane with added methylene diphenyl diisocyanato and 1,6 hexanediols. The diphenyl structure provides stability and sufficient structure reactivity to form a polymer free of byproctucts.  At present aligner technology is using SMART TRACK as aligner material as it is more flexible.

Benefits

  • A transparent and clear design
  • Free from brackets or wires and resultant cuts and ulcerations
  • Improved oral hygiene and periodontal health
  •  patients are free to eat or drink anything during clear aligner therapy
  • Digital planning ensures a predict estimation of treatment time.
  • Patients themselves change the subsequent aligners, requiring fewer dental visits
  • significantly reduced emergency appointments 
  • possible to include teeth with structural anomalies and difficult to bond surface 

Limitations

  • A wear time of 22hrs/day is mandatory for therapy to be effective
  • higher cost
  • initial slurring of speech
  • while wearing or removing if the patient applied excessive fore there may be chances of breakage

How do aligners move teeth?

aligner-based orthodontic treatment involves incremental movement of teeth, by use of multiple successive aligners or trays, each of which progressively repositions teeth by small amount. This incremental movement is brought about by 2 primary mechanisms:

  1. The shape molding effect: The method involves "molding" the movement of the target teeth according to the shape of the aligner used. Activation between the aligner shape and the dental crown geometry generate 3D force system distributed all over the contact surfaces. There are area of intimate contact and relief between the aligner and the tooth surface. A full treatment consists of a set of aligners with sequentially varying shapes, ranging from the initial anatomic geometry to the final tooth positions.



  • Auxiliary elements: Auxiliary elements, such as attachments and power ridges, are used to enhance predictability of specific tooth movements. The strategic arrangements of these auxiliaries in aligners or on the teeth can enhance force delivery. They are used strategically to deliver forces at specific area on the tooth surface.

    • Clear Aligner companies and brands

    • Invisalign
    • ClearCorrect
    • Byte
    • CandidPro
    • SixMonthSmile
    • OrthoFX