The tooth #8 has horizontal root fracture.  The coronal portion is displaced incisally (Fig.2 arrow).  Osteotomy is initiated in the palatal slope; a parallel pin is inserted after 2 mm drill for 21 mm (Fig.5).

Hollowed Crown Last Next Fig.4 Fig.6

Xin Wei, DDS, PhD, MS 1st edition 08/31/2017, last revision 11/18/2018