The aim of this study is to compare the effectiveness of Clear aligners and Conventional braces for upper canine retraction (space closure) regarding canine tipping , anchorage loss and treatment time.

Conventional fixed orthodontic treatment with metal brackets has been rejected by some adult patients because of esthetic and social concerns, but the demand for orthodontic treatment is currently increasing. To satisfy the demands and needs of these patients, the emphasis has shifted toward esthetic orthodontic appliance system. Less noticeable appliances such as ceramic, resin, and lingual brackets, or removable clear appliances such as the Essix and Invisalign (Align Technology, Santa Clara, Calif) provide esthetic orthodontic appliance alternatives.

Since the introduction of clear aligners to the public in 1999, it has become a popular treatment choice for clinicians because of the aesthetics and comfort of the removable clear aligners compared with traditional appliances. Several studies have shown significant limitations of this technique, especially in treating complex malocclusions, whereas other studies have reported successfully treated cases with this removable appliance. A systematic review conducted to determine the treatment effects of clear aligners showed that no strong conclusions could be made regarding the treatment effects of aligners . Therefore, clinical trials were still required to investigate the effectiveness of the Invisalign system.

When using the aligners to correct severe crowding, root positions must be carefully controlled during extraction space closure, and clear aligners must be properly grip all teeth to be moved, Tipping was a common problem in premolar extraction cases during the early years of aligners use. Several previous reports have also discussed the limited ability of thermoplastic appliances to control root-tipping movements and to establish root control comparable to that provided by fixed appliances. The investigators describe the extraction treatment of a patient with moderate to severe tooth crowding using mini screws and clear appliances, thus eliminating the need for conventional brackets.

Inclusion Criteria:

• 1) Moderate to severe crowding orthodontic patients.( Irregularity index of <5 mm)

  2) Good oral hygiene. (Patient with periodontally sound dentition).

  3) Patient in permanent dentition between the age range 16 - 40 years.

  4) .Patients requiring extraction of mandibular and maxillary first premolars;

  5) Patients having sound general health

Exclusion Criteria:

• 1) Systematic disease.

  2) Poor oral hygiene patients.

  3 ) Periodontally affected teeth.