Even if a little part of the tooth structure is visible,the fractured tooth can be saved.This helps in improving your esthetic value which you will understand later. This tooth can be partially built up and you can proceed with three crowns in one piece(i.e joint crowns)instead of a bridge. If you leave it without putting any prosthesis there can be misalignment of the surrounding teeth or supraeruption of opposing teeth creating overall increase in interdental spaces and highly increasing the risk of food lodgement followed by dental caries.

Since the fracture of your tooth is below the gum line(cervical portion of tooth), i suggest you to go for extraction of the same. Since it is posterior area, The occlusal forces are more overthere.. so placeing a post and new crown would not serve you better. So better go for extraction and Immediate Implant. This would give you best results and can avoid unnecessary complications. Leaving the portion of tooth without replacement will lead to major complications. The adjacent teeth may drift to this site which is a major disadvantage... Regards.. Get well soon.