Since the ridge in the incisor region is quite narrow, it appears necessary to place 2 of the smallest 1-piece implants (2x10 or 12 mm, Fig.2,3 (coronal sections)).缺牙牙槽嵴一般上段尖，很快下面变宽。在这种情况下，截除上端牙槽嵴，尽量把植体种深点。偶尔牙槽嵴上下都窄（图二，三），基因决定，拔牙前就窄，可能植骨也无能为力。下前牙区骨质密度高，做劈开术困难。似乎一段式植体勉强过关。

Narrow Ridge Last Next 手术 Xin Wei, DDS, PhD, MS 1st edition 05/17/2019, last revision 12/26/2020