Three-dimensional Evaluation of Pharyngeal Airway Measurements Following Class 2 Correction With Skeletally Anchored Herbst Appliance
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 10
- 试验地点
- 1
- 主要终点
- three dimensional evaluation of pharyngeal airway volume
研究概览
简要总结
Ten adolescent female patients with Class 2 mandibular deficiency with a mean age of 16.5 ±1.71 years treated with type IV Herbst appliance.
Skeletally anchored appliance was connected directly to the mandible by a bilateral reconstruction bone plates to provide a skeletal anchorage, while connected to the maxilla through dental splint connecting upper canine, first premolar, first and second molars through the use of orthodontic bands connected together palatally by a heavy 1mm stainless steel wire.
The treatment duration was 9 months, then the appliances were removed,The Cone Beam Computed Tomography (CBCT) scans were taken before and immediately after Herbst treatment to analyse airway volume, also 3D measurement of the effective mandibular length has been taken. Cephalometric film was extracted from CBCT scans and analysed for dentoskeletal and soft tissue changes.
详细描述
The Herbst appliance was anchored by two reconstruction plates located bilaterally in the mandible between the canine and first premolar, while attached to the maxilla through dental splints utilizing orthodontic bands.
For each patient, two reconstruction plates were sent to the laboratory for LASER welding of the Herbst bases to the first hole of each reconstruction plate. This assembly was projected transmucosal and exposed into the oral cavity for direct connection with the Herbst appliance.
3D model for the mandible of each patient was printed with 3D printer machine after extracted from the patient CBCT.
The reconstruction plates were bended using a 3-jaw contouring and bending plier to be adapted to the printed model on the predetermined location between mandibular canine and 1st premolar bilaterally.Sterilization of the reconstruction plates were then preformed.
For surgical placement of reconstruction plates, An envelope flap with one releasing incision (three-corner flap)was made starting with the horizontal incision 3-mm apical to the gingival crest from the mesial surface of lower second premolar to the distal surface of lower lateral incisor on one side, then a vertical incision was made at the mesial end of the horizontal incision, extending apically to the chin level to allow unstrained placement of the reconstruction plate. The same procedures were performed on the other side.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 14 Years 至 20 Years（Child, Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Skeletal and dental Class II malocclusion due to mandibular retrusion (SNB≤ 76° )
- •Overjet ≥ 5.0 mm
- •Normal or low FMA angle (≤ 28)
- •Complete permanent dentition, excluding the third molars
- •Minimum or no crowding in the mandibular arch
- •All the patient involved in the study will be in stages 5 and 6 based on the modified cervical vertebral maturation stages (CVMS).
排除标准
- •History of any medical problems that may interfere with orthodontic treatment
- •Previous orthodontic treatment.
- •Clinical signs and symptoms of temporomandibular disorders.
- •Mandibular asymmetries.
- •Bad oral hygiene.
研究组 & 干预措施
skeletal class 2 malocclusion
10 patients treated with type IV Herbst appliance. The appliance was connected directly to the mandible by a bilateral reconstruction bone plates to provide a skeletal anchorage and avoid any mandibular teeth involvement
干预措施: Herbst fixed functional appliance (Device)
结局指标
主要结局
three dimensional evaluation of pharyngeal airway volume
时间窗: 9 months
The air way analysis option was chosen to start the measurement. The nasopharynx, velopharynx, glossopharyngeal and the total air way horizontal boundaries all had been set parallel to Frankfort horizontal The vertical anterior boundary of pharyngeal airway was represented by the line perpendicular to FH plane and tangent to PNS. A quick method for determining the airway sensitivity has been chosen using a threshold value of 70 unit which was find optimum for airway segmentation. Consequently, the software was automatically converted the segmented airway into 3D volume. The 3D air way volume for the nasopharynx, velopharynx and glossopharyngeal as well as the total pharyngeal airway were calculated and tabulated.
次要结局
- dento-skeletal changes(9 months)
研究者
Khaled ELHabbak
principal investigator
Al-Azhar University