Thirty two patients requiring extraction of maxillary first premolars and en-masse retraction of upper anterior teeth will participate in the study. They will be divided randomly into two groups: electrical group and control group. In each group, en-masse retraction will be initiated after completion of the leveling and alignment phase via closed nickel-titanium coil springs applying 250 g of force per side, Mini-implants will be used as an anchor unit. The overall retraction duration will be calculated. The skeletal, dental and soft tissue changes will be detected using panoramic and lateral cephalometric radiographs which will be obtained pretreatment, pre and post en-masse retraction of the anterior teeth.
Prior to enrollment of each subject into the study, they will be examined completely to determine the orthodontic treatment plan. The operator will inform them about the aim of the study and ask them to provide a written informed consent. Self-drilling titanium mini-implants (1.6mm diameter and 8mm length) will be used. They will be inserted between the maxillary second premolar and first molar at approximately 8-10 mm above the archwires at the mucogingival junction and will be checked for primary stability (mechanical retention). Then the maxillary first premolar will be extracted. The maxillary arch will be levelled and aligned. The rectangular stainless steel archwires (0.019" × 0.025") with anterior 8mm height soldered hooks distal to the canines will be inserted. A removable device containing a small electrical circuit will be applied to each patient to supply the required electric current. Each patient in the electrical group will be asked to wear a removable device containing a small electrical circuit that will supply the required electric current for five hours a day until the completion the retraction of the upper anterior teeth. (250-300) g force will be applied on each side using two NiTi springs attached between the mini-implants and the soldered hooks in a direction approximately parallel to the occlusal plane for conducting an en-masse retraction. The force level will be measured every 2 weeks. Retraction will be stopped when a class I canine relationship will be achieved and a good incisor relationship will be obtained. The duration of retraction will be calculated by calculating the time required to achieve complete retraction of the upper anterior teeth through clinical examination. Panoramic and lateral cephalometric radiographs will be obtained pretreatment, pre and post en-masse retraction of the anterior teeth, to assess the skeletal, dental and soft tissue changes. Periodontal health will be assessed at the beginning of orthodontic treatment, before and after en-masse retraction by evaluating the following parameters: plaque index, gingival index, bleeding index, probing depth and gingival recession.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
SINGLE
Enrollment
32
Each patient in the electrical group will be asked to wear a removable device containing a small electrical circuit that will supply the required electric current for five hours a day until the completion the retraction of the upper anterior teeth.
The maxillary arch will be levelled and aligned. The rectangular stainless steel archwires (0.019" × 0.025") with anterior 8mm height soldered hooks distal to the canines will be inserted. (250-300) g force will be applied on each side using two NiTi springs attached between the mini-implants and the soldered hooks in a direction approximately parallel to the occlusal plane for conducting an en-masse retraction.
University of Damascus
Damascus, Syria
Duration of en-masse retraction of anterior teeth
Assessment will be performed by calculating the time required to achieve complete retraction of the upper anterior teeth (six teeth) through clinical examination.
Time frame: The months required to complete the retraction procedure will be recorded. Completion of this procedure is expected to be occur within six months in the experimental group and eight months in the control group.
Change in the SN-U1 angle
This angle the represents the relationship of the upper anterior teeth with SN in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken and this angle is going to be measured in degrees.
Time frame: : The cephalogram will be taken twice, 1 week before the commencement of the retraction and at the completion of retraction. Completion of this procedure is expected to be done within 6 months in the experimental group and 8 months in the control group.
Change in the SNA angle
This angle the represents the position of the upper jaw in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken and this angle is going to be measured in degrees.
Time frame: : The cephalogram will be taken twice, 1 week before the commencement of the retraction and at the completion of retraction. Completion of this procedure is expected to be done within 6 months in the experimental group and 8 months in the control group.
Change in the MM angle
This angle the represents the amount of vertical divergence between the upper and lower jaws in the cephalometric analysis. Lateral cephalograms will be taken and this angle is going to be measured in degrees.
Time frame: : The cephalogram will be taken twice, 1 week before the commencement of the retraction and at the completion of retraction. Completion of this procedure is expected to be done within 6 months in the experimental group and 8 months in the control group.
Change in the Nasolabial angle
This angle the represents the relationship of the upper lip with nose in the cephalometric analysis. Lateral cephalograms will be taken and this angle is going to be measured in degrees.
Time frame: : The cephalogram will be taken twice, 1 week before the commencement of the retraction and at the completion of retraction. Completion of this procedure is expected to be done within 6 months in the experimental group and 8 months in the control group.
Change in the Li-E Line
This measurement represents the relationship between the upper lip and the Ricketts line in cephalometric analysis. Lateral cephalograms will be taken and this variable will be measured in mm.
Time frame: : The cephalogram will be taken twice, 1 week before the commencement of the retraction and at the completion of retraction. Completion of this procedure is expected to be done within 6 months in the experimental group and 8 months in the control group.
Change in Root Length
The root length will be measured for each root of six upper anterior teeth using panorama imaging, the change will be calculated between before and after images in mm.
Time frame: This will be measured: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.
Change in the Plaque index
The plaque index will be used to assess the status of the oral hygiene in these patients.
Time frame: This will be measured: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.
Change in the Gingival Index
The Gingival index will be used to assess the status of the gingival tissues around the teeth.
Time frame: This will be measured: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Change in the Bleeding Index
The Bleeding index will be used to assess the status of periodontal tissues and the amount of congestion in the gingival margins around the anterior teeth.
Time frame: This will be measured: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.
Change in the Probing Depth
This will be measured in millimeters from the gingival margin to the bottom of the sulcus/pocket around the six anterior teeth.
Time frame: Two measurements are required for this calculation: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.
Change in the Gingival Recession
This will be measured in millimeters from the cement-enamel junction to the level of the gingival margin around the six anterior teeth.
Time frame: Two measurements are required for this calculation: one day before the commencement of the retraction phase and at the end of the retraction phase which is expected to occur within 6 months in the experimental group and 8 months in the control group.