regeneration是什么（什么是PreservationRhinoplasty丹尼尔为什么提倡这个概念）

Management of the nasal dorsum remains a challenge in rhinoplasty surgery, with many reduction rhinoplasties resulting in destruction of the key-stone area. This may require reconstruction with either spreader grafts or spreader flaps, both for aesthetic and functional reasons. Dr Baris Cakir, internationally renowned for his conceptualization of the “polygon rhinoplasty” in tip surface aesthetics with co-author Dr Rollin Daniel advocates the use of dorsal preservation via an (1) endonasal approach (2) removal of a septal strip in the subdorsal area whose shape and height are determined preoperatively (3) complete lateral, transverse and radix osteotomies and (4) dorsal reduction, utilizing a let down operation (LDO) or a push down operation (PDO) (Figure 1).3,4 The LDO consists of a maxillary wedge resection and is performed in patients who need more than 4mm if lowering, whereas the PDO consists of downward impaction of the fully mobilised nasal pyramid and is utilized in patients with smaller humps (<4mm). This technique of dorsal preservation results in more natural postoperative dorsum lines, with fewer dorsal irregularities, inverted-V deformities or need for midvault reconstruction in selected primary patients.4Furthermore, dissection is performed in a complete subperichondrial plane to minimise soft tissue disruption, resulting in less scar tissue formation and preservation of ligamentous structures.5Intra-operatively the scroll ligament and Pitanguy’s midline ligament are repaired to stabilize the internal valve and tip position, and long-term post operatively preserve tip definition and elasticity, respectively.

翻译如下：

鼻背仍然是鼻成形术手术中的一个挑战，许多减少的鼻整形导致了关键的结石区的破坏。这可能需要重建或扩张器移植物或扩张皮瓣，无论是美学和功能的原因。Baris Cakir博士，以他与合著者Rollin Daniel博士在尖端表面美学中对“多边形鼻成形术”的概念化而闻名，他提倡通过(1)鼻内入路(2)切除在背下区的隔带，其形状和高度在术前确定(3)完全的侧、横、基骨性切开术和(4)背侧复位，使用松驰手术(LDO)或向下推倒手术(图1)。3，4 LDO由上颌骨楔形切除术组成，如果下降需要超过4mm，则行LDO手术，而PDO是由完全活动的鼻金字塔向下撞击而成，用于较小的驼峰患者(<4mm)。这种背侧保存技术使术后背线更加自然，在选定的原发患者中，背侧不规则、倒置-V畸形或需要重建中穹窿的情况较少。

此外，在一个完整的软骨下平面进行解剖，以尽量减少软组织破坏，减少疤痕组织形成和保留韧带结构。