Cephalometric measurements

The pretreatment (T1) and posttreatment (T2) lateral cephalographs were digitized using an imaging software, V-Ceph 5.5 (Cybermed, Seoul, Korea), which was also used to calculate the linear and angular dimensions on the basis of the landmarks according to the definitions given in Figures 1, ​,2,2, and ​and33.

Pt, Pterygoid; Or, orbitale; U, upper; L, lower; UL, upper lip; LL, lower lip; FH, Frankfort horizontal plane; HRL, horizontal reference line; VRL, vertical reference line; TVL, true vertical line; MeGo, menton to gonion line; Perp to MeGo, perpendicular line to MeGo passing the pogonion; 1, U1 crown to HRL; 2, U1 crown to VRL; 3, U1 apex to HRL; 4, U1 apex to VRL; 5, U6 crown to HRL; 6, U6 crown to VRL; 7, U6 apex to HRL; 8, U6 apex to VRL; 9, U7 crown to HRL; 10, U7 crown to VRL; 11, U7 apex to HRL; 12, U7 apex to VRL; 13, L1 crown to HRL; 14, L1 crown to VRL; 15, L1 apex to HRL; 16, L1 apex to VRL; 17, L6 crown to HRL; 18, L6 crown to VRL; 19, L6 apex to HRL; 20, L6 apex to VRL; 21, L7 crown to HRL; 22, L7 crown to VRL; 23, L7 apex to HRL; 24, L7 apex to VRL; 25, overjet; 26, overbite; 27, UL to TVL; 28, LL to TVL; 29, soft tissue A point to VRL; 30, soft tissue B point to VRL.

SN, Sella-nasion; FH, Frankfort horizontal plane; Go, gonion; Me, menton; U, upper; L, lower; 1, SNA; 2, ANB; 3, occlusal plane angle; 4, SN to mandibular plane angle; 5, U1 to FH angle; 6, U6 to FH angle; 7, U7 to FH angle; 8, L1 to FH angle; 9, L6 to FH angle; 10, L7 to FH angle; 11, nasolabial angle; 12, mentolabial angle.

Go, Gonion; Me, menton; mVRL, mandibular vertical reference line; Perp to, perpendicular to; L, lower; 1, L1 crown to mVRL; 2, L1 crown to GoMe; 3, L1 apex to mVRL; 4, L1 apex to GoMe; 5, L6 crown to mVRL; 6, L1 crown to GoMe; 7, L6 apex to mVRL; 8, L6 apex to GoMe; 9, L7 crown to mVRL; 10, L7 crown to GoMe; 11, L7 apex to mVRL; 12, L7 apex to GoMe; 13, L1 to GoMe angle; 14, L6 to GoMe angle; 15, L7 to GoMe angle.

The horizontal reference line (HRL) was the Frankfort horizontal plane, and the vertical reference line (VRL) was a perpendicular line passing through the pterygoid point. In order to evaluate the movement of mandibular dentition within the mandible itself, the variables pertaining to the mandibular incisors and molars were re-analyzed in reference to the mandibular plane as a new mandibular HRL (mHRL: MeGo), and the line perpendicular to the mHRL and passing through the pogonion as a new mandibular VRL (mVRL: Perp to MeGo).

Fifty-eight linear and angular measurements were made by one examiner (HJL), and the variables at T1 and T2, and the differences between T1 and T2, were calculated. In order to access the accuracy and reliability of the measurements, 10 cases were randomly selected from each group for re-digitization and reanalysis at an interval of at least 2 weeks between the two measurements by the same examiner. Intraexaminer reliability was evaluated using the intraclass correlation coefficient, which was greater than 0.90 for all variables.