Adusumilli Sai Prakash, Sudhakar P, Mummidi Bhaskar, Varma D Praveen Kumar, Arora Sunil, Radhika A, Maheshwari Amit
Department of Orthodontics, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India.
J Contemp Dent Pract. 2012 Nov 1;13(6):918-24. doi: 10.5005/jp-journals-10024-1254.
The present case report describes the importance of understanding of biomechanical and clinical considerations in application of Forsus appliance in correction of class II skeletal malocclusion.
Angle's class II malocclusion is one of the most prevailing that may be either skeletal or dental presenting with different clinical manifestations. There are number of appliances to treat such a malocclusion in a growing child. Fixed functional appliances are indicated for class II corrections in patients who report late with minimal residual growth left.
A case of class II skeletal and dental malocclusion treated with preadjusted edgewise appliance supplemented with Forsus Fatigue Resistant Device (FRD) (3M Unitek Corp, California, USA) is reported.
Forsus device is an effective alternative in treating moderate skeletal class II malocclusion. The Forsus FRD (3M Unitek Corp, California, USA) can be used instead of class II elastics in mild cases and in place of Herbst appliance in severe cases. Alteration of force vector by modifying the archwire as shown in this case report while applying Forsus and incorporation of 10 degree labial root torque in lower archwire will minimize the effects on dentition. Engaging modules or tubing on to the pushrod and leaving 1 to 2 mm clearance between distal end of the upper tube and L-pin as shown in this case report will significantly improve the patient compliance.
Much emphasis should be given to biomechanical considerations which were discussed in this article while treating patients with Forsus to prevent the unwanted effects. Clinical considerations and certain modifications advised in this case report should be utilized while treating class II skeletal malocclusions with Forsus appliance to eliminate the patient cooperation factor and make treatment time estimates much more accurate.
本病例报告阐述了在应用 Forsus 矫治器矫正安氏 II 类骨性错颌畸形时，理解生物力学和临床因素的重要性。
安氏 II 类错颌畸形是最常见的错颌畸形之一，可分为骨性或牙性，具有不同的临床表现。有多种矫治器可用于治疗生长发育期儿童的此类错颌畸形。固定功能矫治器适用于生长发育后期、剩余生长量较小的 II 类错颌畸形患者。
报告一例安氏 II 类骨性和牙性错颌畸形病例，采用预成方丝弓矫治器并辅以 Forsus 抗疲劳装置（FRD，美国加利福尼亚州 3M Unitek 公司）进行治疗。
Forsus 装置是治疗中度骨性 II 类错颌畸形的有效替代方法。Forsus FRD（美国加利福尼亚州 3M Unitek 公司）在轻度病例中可替代 II 类牵引橡皮圈，在重度病例中可替代 Herbst 矫治器。如本病例报告所示，在应用 Forsus 时通过调整弓丝改变力的方向，并在下颌弓丝中加入 10 度的唇向牙根转矩，可将对牙列的影响降至最低。如本病例报告所示，将模块或 tubing 套在推杆上，并在上颌管远端与 L 形栓之间留出 1 至 2 毫米的间隙，可显著提高患者的依从性。
在使用 Forsus 治疗患者时，应高度重视本文讨论的生物力学因素，以防止出现不良影响。在使用 Forsus 矫治器治疗安氏 II 类骨性错颌畸形时，应采用本病例报告中建议的临床考虑因素和某些调整方法，以消除患者合作因素的影响，使治疗时间的预估更加准确。
