Homecrown during 3/4 crown preparation on premolar, bur used to add retentive grooves publisher :NIL NAM -June 23, 2017 during 3/4 crown preparation on premolar, bur used to add retentive grooves is: - radial fissure. Labels crown Facebook Twitter Share:during 3/4 crown preparation on premolar, bur used to add retentive grooves Facebook Twitter WhatsApp Pinterest LinkedIn Reddit Tumblr Telegram Email