[Application of bolt-like post crown system in restoration of molar residual root and crown with low occlusogingival distance].

Purpose: To evaluate the clinical effects of bolt-like post crown system in restoration of molar residual root and crown with low occlusogingival distance and large root bifurcation angle.

Methods: Thirty two molar residual roots and crowns from 25 patients with low occlusogingival distance (<4 mm) and large root bifurcation angle were involved in this study. First, the root canals were prepared according to their natural directions following the standard procedures.