Abstract：
The case in this study had moderate hypodontia, with both lower lateral incisors and the lower-left second premolar missing. A Class II division 2 relationship with severe crowding in the upper arch and a traumatic deep bite over a skeletal I base complicated the occlusion.
The plan was to extract the upper first premolars to relieve upper arch crowding and the lower-left impacted second premolar to preserve the bilateral class I molar relationship. A class I occlusal relationship was achieved through space opening in the lower lateral incisors region and space closure in the upper and lower premolars regions.
The use of orthodontic screws for bite opening and anterior segment retraction, in conjunction with bi-metric slot size selection in bracket prescription, was effective in controlling incisor inclination and interincisal angle. The use of an implant fixture before beginning the finishing stage allowed for a reduction in total treatment time and facilitated the provision of the final prosthesis before debonding the case. As a result, the patient was able to receive a satisfactory occlusion on the day of debonding.
This case of moderate hypodontia was successfully resolved by combining space closure and space opening effectively. To solve the arch problems in such Class II division 2 cases with severe crowding, extractions were required. To complete the case, this was combined with intrusive and retractive mechanics. In hypodontia cases, implants are an excellent choice for both aesthetics and functional restoration.
The plan was to extract the upper first premolars to relieve upper arch crowding and the lower-left impacted second premolar to preserve the bilateral class I molar relationship. A class I occlusal relationship was achieved through space opening in the lower lateral incisors region and space closure in the upper and lower premolars regions.
The use of orthodontic screws for bite opening and anterior segment retraction, in conjunction with bi-metric slot size selection in bracket prescription, was effective in controlling incisor inclination and interincisal angle. The use of an implant fixture before beginning the finishing stage allowed for a reduction in total treatment time and facilitated the provision of the final prosthesis before debonding the case. As a result, the patient was able to receive a satisfactory occlusion on the day of debonding.
This case of moderate hypodontia was successfully resolved by combining space closure and space opening effectively. To solve the arch problems in such Class II division 2 cases with severe crowding, extractions were required. To complete the case, this was combined with intrusive and retractive mechanics. In hypodontia cases, implants are an excellent choice for both aesthetics and functional restoration.
摘要：
背景：本研究中的病例有中度牙痛，下侧切牙和左下第二磨牙缺失。II类2级关系与上弓严重拥挤以及骨骼I基部上的创伤性深咬伤使咬合变得复杂。
方法：该计划是提取上第一前磨牙以减轻上弓拥挤，并提取左下第二前磨牙以保持双侧I类磨牙关系。通过下侧切牙区域的空间开口和上前磨牙和下前磨牙区域的空间闭合，实现了I类咬合关系。
结果：使用正畸螺钉进行咬合开口和前段回缩，结合括号处方中的双度量时隙大小选择，能有效控制切牙倾角和切角。在开始整理阶段之前使用植入物夹具可以减少总治疗时间，并有助于在脱粘病例之前提供最终假体。因此,患者能够在脱粘当天获得令人满意的封堵。
结论：通过有效地结合空间封闭和空间开放，成功解决了这种中度牙髓不足的情况。为了解决此类II类2例严重拥挤的拱门问题，需要提取。为了完成这个案子，这与侵入性和回缩力学相结合。在缺牙症病例中，植入物是美学和功能恢复的绝佳选择。
方法：该计划是提取上第一前磨牙以减轻上弓拥挤，并提取左下第二前磨牙以保持双侧I类磨牙关系。通过下侧切牙区域的空间开口和上前磨牙和下前磨牙区域的空间闭合，实现了I类咬合关系。
结果：使用正畸螺钉进行咬合开口和前段回缩，结合括号处方中的双度量时隙大小选择，能有效控制切牙倾角和切角。在开始整理阶段之前使用植入物夹具可以减少总治疗时间，并有助于在脱粘病例之前提供最终假体。因此,患者能够在脱粘当天获得令人满意的封堵。
结论：通过有效地结合空间封闭和空间开放，成功解决了这种中度牙髓不足的情况。为了解决此类II类2例严重拥挤的拱门问题，需要提取。为了完成这个案子，这与侵入性和回缩力学相结合。在缺牙症病例中，植入物是美学和功能恢复的绝佳选择。
