A dental appliance, comprising: an archwire configured to apply corrective force to a tooth, wherein the archwire has a rectangular cross-section; and an orthodontic bracket (100, 200), comprising: a backend surface adapted for attachment; a frontend surface opposite the backend surface; a first side surface connected between the backend surface and the frontend surface; a second side surface connected between the backend surface and the frontend surface, opposite the first side surface; and a passageway (103, 203) extending from the first side surface to the second side surface, the cross-section of the passageway (103, 203) including an access opening (103A, 203A), an archwire slot (103B, 203B), a path portion (103C, 203C), and at least one circular rotation portion (103D, 203D), wherein the access opening (103A, 203A) is configured to allow the archwire to enter the passageway (103, 203), the archwire slot (103B, 203B) is formed at the end of the passageway (103, 203) to receive the archwire, and the path portion (103C, 203C) connects the access opening (103A, 203A) and the archwire slot (103B, 203B), wherein the width of the narrowest part of the path portion (103C, 203C) is greater than a short side of the rectangular cross-section of the archwire, and the circular rotation portion (103D, 203D) is provided in the path portion (103C, 203C) and has a diameter (W') large enough to accommodate a diagonal length of the rectangular cross-section of the archwire so as to allow the archwire to rotate and change its orientation. an archwire configured to apply corrective force to a tooth, wherein the archwire has a rectangular cross-section; and an orthodontic bracket (100, 200), comprising: a backend surface adapted for attachment; a frontend surface opposite the backend surface; a first side surface connected between the backend surface and the frontend surface; a second side surface connected between the backend surface and the frontend surface, opposite the first side surface; and a passageway (103, 203) extending from the first side surface to the second side surface, the cross-section of the passageway (103, 203) including an access opening (103A, 203A), an archwire slot (103B, 203B), a path portion (103C, 203C), and at least one circular rotation portion (103D, 203D), wherein the access opening (103A, 203A) is configured to allow the archwire to enter the passageway (103, 203), the archwire slot (103B, 203B) is formed at the end of the passageway (103, 203) to receive the archwire, and the path portion (103C, 203C) connects the access opening (103A, 203A) and the archwire slot (103B, 203B), wherein the width of the narrowest part of the path portion (103C, 203C) is greater than a short side of the rectangular cross-section of the archwire, and the circular rotation portion (103D, 203D) is provided in the path portion (103C, 203C) and has a diameter (W') large enough to accommodate a diagonal length of the rectangular cross-section of the archwire so as to allow the archwire to rotate and change its orientation. a backend surface adapted for attachment; a frontend surface opposite the backend surface; a first side surface connected between the backend surface and the frontend surface; a second side surface connected between the backend surface and the frontend surface, opposite the first side surface; and a passageway (103, 203) extending from the first side surface to the second side surface, the cross-section of the passageway (103, 203) including an access opening (103A, 203A), an archwire slot (103B, 203B), a path portion (103C, 203C), and at least one circular rotation portion (103D, 203D), wherein the access opening (103A, 203A) is configured to allow the archwire to enter the passageway (103, 203), the archwire slot (103B, 203B) is formed at the end of the passageway (103, 203) to receive the archwire, and the path portion (103C, 203C) connects the access opening (103A, 203A) and the archwire slot (103B, 203B), wherein the width of the narrowest part of the path portion (103C, 203C) is greater than a short side of the rectangular cross-section of the archwire, and the circular rotation portion (103D, 203D) is provided in the path portion (103C, 203C) and has a diameter (W') large enough to accommodate a diagonal length of the rectangular cross-section of the archwire so as to allow the archwire to rotate and change its orientation.