Posterior panoramic X-ray taken immediately pre banding shows impaction of LL7,  blocked by LL8 (Fig.14).   There appear to be a cyst and a tunnel coronal to LL7 (Fig.14 *, T).   CT is mandatory.

The tooth bud of LL8 appears to be close to that of LL7 at the age of 7.5 years (Fig.5).病人7岁时左下智齿牙胚好像已经接近7（图五与右侧比较）。现在左下七冠方仿佛有牙囊（图十四*）和隧道（T）。拔除智齿时，七牙合面骨质应该去除。术前将拍摄CT。

Discrepancy     Last     Next     Low Magnification of 5, 14

Xin Wei, DDS, PhD, MS 1st edition 06/26/2020, last revision 08/15/2020

https://www.journalmc.org/index.php/JMC/article/view/272/210#:~:text=The%20incidence%20impaction%20of%20the%20permanent%20lower%20second,second%20molar%20is%20more%20common%20than%20bilateral%20impaction.