• Changes that occur in the dentoalveolar vertical development of the upper and lower anterior teeth will help to know the effect of skeletally anchored extrusion arch on the vertical development of the anterior teeth.
• Change will be measured on pretreatment and posttreatment digital study models by measuring The perpendicular vertical distance from a point between the central incisors at the level of the alveolar process to the occlusal plane from the frontal view, the occlusal plane was determined by three points: mesiobuccal cusp tip of the right and left first permanent molars and cusp tip of the right first premolar in millimeters (mm).
• Also will be measured on pretreatment and posttreatment digital study models by measuring the vertical distance between the incisal edge and gingival margin of the central incisor along its labial surface, the mean between the right and left sides will be used in millimeters(mm).

• This outcome will help to know the effect of skeletally anchored extrusion arch on the upper and lower arch length, perimeter and intermolar width.
• Change will be measured on pretreatment and posttreatment digital study models by measuring the perpendicular distance between a line connecting the mesial aspects of the permanent first molars and the contact point between the central incisors (arch length) in millimeters(mm), measuring the sum of four segments: from the mesial surface of the permanent first molar to the mesial contact point of the canine and then to the contact point of the central incisors, measured on the right and left sides (arch perimeter)in millimeters (mm) and measuring the linear distance between right and left first permanent molar (intermolar width) in millimeters (mm).

• This outcome will help to know the effect of skeletally anchored extrusion arch on the dentofacial structures in patients with anterior open bite.
• Measurements will be done on pretreatment and posttreatment lateral cephalometric radiographs:
• SNA(°)/SNB(°)/ANB(°) will show changes in skeletal antero-posterior relationship between maxilla and mandible.
• MP(Me-GO)-SN(°)/Palato-mandibular plane(°)/FH-OP(°)/FH-PP(°)/Gonial angle(°) will show skeletal vertical changes.
• Occlusal plane- SN (°) will show dental vertical changes.
• L1-MP(°)(IMPA)/U1-PP(°)/Interincisal angle(°) will show dental incisor inclination.
• Nasolabial angle(°) will show Soft tissues changes.

• This outcome will help to know the effect of skeletally anchored extrusion arch on the dentofacial structures in patients with anterior open bite.
• Measurements will be done on pretreatment and posttreatment lateral cephalometric radiographs:
• Witts(mm) will show changes in skeletal antero-posterior relationship between maxilla and mandible.
• ALFH(ANS-Me)(mm)/A-ANS(mm)/N-Me(mm)/Co-GO(mm) will show skeletal vertical changes.
• U6-PP(mm)/U1-pp(mm)/L6-MP(mm)/L1-MP(mm) will show dental vertical changes.
• U1-Eplane(mm)/L1-Eplane(mm) will show Soft tissues changes.

This outcome will help to know the effect of extrusion of the anterior teeth on the smile of the patients.

Pretreatment and posttreatment extraoral photographs will be taken, including a close-up photograph with a ruler while the patient is smiling.

This outcome will help to know the stability of the technique of using of skeletally anchored extrusion arch in the treatment of anterior open bite patients.

-stability will be measured on posttreatment after 1, 2 and 3 years posttreatment digital study models by measuring the vertical linear distance between the mesiodistal midpoint of the incisal edge of the uppermost vertically erupted upper central incisors and a horizontal plane projected on the lower central incisor(overbite) in millimeters(mm).