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العنوان
Three-dimensional Evaluation of a Clear Mandibular Advancement Appliance Based on the Twin-block Design /
المؤلف
Zaky, Ahmed Mostafa Mahmoud.
هيئة الاعداد
باحث / Ahmed Mostafa Mahmoud Zaky
مشرف / Khaled Mostafa Fawzy
مشرف / Ibrahim Mazen Negm
مناقش / Ibrahim Mazen Negm
تاريخ النشر
2018.
عدد الصفحات
269 P. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
Orthodontics
تاريخ الإجازة
1/1/2018
مكان الإجازة
جامعة عين شمس - كلية طب الأسنان - قسم تقويم الاسنان
الفهرس
Only 14 pages are availabe for public view

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Abstract

This prospective clinical trial was performed to evaluate the effects of a modification of the Twin-block functional appliance developed by Clark. The new appliance consisted of upper and lower vacuum pressed sheets incorporating advancement bite ramps which forces the patient to posture the mandible forwards during rest. Patients were first diagnosed clinically for the need of mandibular advancement functional appliance therapy. After the preliminary diagnosis for the presence of mandibular deficiency, a lateral cephalometric radiograph was obtained to confirm the skeletal mandibular deficiency and to know the skeletal age of the patient through cervical vertebrae maturation analysis.
This was followed by obtaining the normal diagnostic records for each patient. To perform a 3D evaluation of the changes that happened to the skeletal and dentoalveolar structures, CBCT scan was performed prior to fitting of the appliance. Upper and lower impressions and a functional bite with the patient occluding in an edge to edge relationship were obtained for appliance construction.
George Gauge was used for construction of the functional bite to standardize both the mandibular advancement and the vertical separation. The appliance was fabricated through vacuum pressing 1.5mm thermoplastic sheets on the models followed by building up acrylic resin bite ramps to aid in advancement of the mandible while wearing the appliance.
The appliance was delivered, and the patient was instructed to wear it for 22 hours/day starting with 2 hours and increasing its wear gradually every
190 A.Zaky PhD thesis
day until reaching 22 hours daily. Patients were inspected every 4 weeks for appliance fit and any discomforts were alleviated. A wearing log was delivered for each patient to keep track of the patient’s compliance and it was found that keeping a wear log served as a reminder for wearing the appliance and increased their compliance.
The appliance was worn for 12 months or when the patient reached an edge to edge bite whichever was closer. The average appliance wear duration was 10.5 months. The patient was then examined for the need of a second phase of therapy. If the patient was ready for the second phase of fixed appliance therapy, she was immediately transitioned however if the patient was not ready for any reason such as unerupted teeth, the appliance was continued as a retainer in the form of night time only wear.
A post-operative CBCT was obtained at the end of the functional appliance therapy phase to evaluate the skeletal, dentoalveolar and soft tissue effects in 3 dimensions.
After performing the necessary measurements, these measurements were statistically analyzed to obtain the results of the study.