Effectiveness and Uses of Clear Aligners
- A 2014 systematic review found insufficient evidence to determine the effectiveness of clear aligners.
- Clear aligners are likely useful for moderate front-teeth crowding, but less effective for teeth that are too far forward or backward, or rotated in the socket.
- Cases of relapse of the anterior teeth have been found with clear aligners compared to conventional braces.
- A 2013 Cochrane review found no high-quality evidence for managing the recurrence of lower-front-teeth misalignment.

Application and Manufacturing of Clear Aligners
- Treatment begins with diagnostic x-rays, photographs, and capturing the patient's bite, teeth, and gums.
- Dental impressions are scanned to create a digital 3D representation of the teeth.
- Technicians use software programs to move the teeth to the desired location and create aligners.
- Each aligner moves teeth between 0.25 to 0.33 millimeters.
- Additional rounds of aligners, known as Refinements, may be necessary for desired tooth positions.
- Aligners are modeled using CAD/CAM software and manufactured using stereolithography.
- The molds for aligners are built in layers using a photo-sensitive liquid resin cured by a laser.
- Clear aligners are made from an elastic thermoplastic material that applies pressure to move teeth.
- Tooth-colored composite attachments may be bonded onto certain teeth for rotation or pulling down.
- Attachments or interproximal reduction may be used to facilitate movement or improve fit.

Treatment Process and Brands of Clear Aligners
- Each aligner is worn for 22 hours a day for one to two weeks.
- The average treatment time is 13.5 months, varying based on the complexity of teeth movements.
- Aligners are removed for brushing, flossing, and eating, but hot liquids should be avoided.
- After treatment, patients are advised to wear a retainer at night.
- Invisalign, manufactured by Align Technology, has treated over 12.2 million patients.
- Align Technology was founded in 1997 by Zia Chishti and sales began in the U.S. in 1999.
- Orthoclear, developed by Zia Chishti after leaving Align Technology, resulted in legal disputes and a settlement in 2006.
- ClearCorrect, established in 2006, was named the fastest-growing health company in America in 2011.
- ClearCorrect's align system has been used to treat about 80,000 patients.
- SmileDirectClub was launched in 2014 as an alternative to in-office clear aligners.
- Smile White is a UK-based company that offers clear aligners.

Direct-to-Consumer Clear Aligner Services
- Following SmileDirectClub, multiple companies provide aligner treatment to patients through mail and digital platforms.
- The American Association of Orthodontists released a consumer alert explaining potential risks associated with such services.

Controversies, Legal Issues, and Costs
- Lawsuits have been common in the clear aligner market.
- ClearCorrect and Align Technology had patent disputes, resulting in an agreement and payment of $20 million.
- Align Technology required doctors prescribing Invisalign to complete a minimum number of cases and training, leading to certifications being suspended and a class action lawsuit.
- ClearCorrect filed a declaratory judgment against Align Technology, claiming invalid patents.
- Align Technology filed lawsuits against ClearCorrect, alleging unfair practices and patent infringement.
- The cost of clear aligners is typically lower than all-metal braces.
- Prices are influenced by factors such as treatment details, time/age of treatment, location, and the experience of the orthodontist.
- In countries like Australia, Canada, United States, and United Kingdom, prices are fairly similar at around $2,000/£1,500.
- Direct-to-consumer clear aligner companies have faced criticism and scrutiny from dental professionals.
- The American Association of Orthodontists has issued consumer alerts regarding the potential risks of using direct-to-consumer clear aligner companies.
- Invisalign, one of the leading clear aligner brands, has faced a class-action lawsuit and settlement.