Apical 3 mm Underdrill Post Cortical Drill M
Following light use of 4 mm tissue punch, a buccal incision is made and raised. After 4x8.5 mm drill with 10.5 mm offset at #19, 4.5 mm cortical drill is used for 2/3 length to take care of the thick dense lingual plate (overprep). The remaining apical 3 mm osteotomy is underdrill (3.5 mm). After try-in of a 4.5x14 mm tissue-level dummy implant, a same-sized definitive one obtains 35 Ncm torque (Fig.1). Following 3-4 more turns, the torque reaches 45 Ncm (Fig.2) with the distal thread covered (<) and autogenous bone graft placed in the distal defect (*). A 4x3 mm unipost is placed to keep periodontal dressing in place. Clinically the implant is placed within bone boundary buccolingually. The new implant seems necessary considering short (Fig.2 S) and probably resorbed (Fig.1 R) roots of the premolars. In fact the short abutment keeps the mesiolingual portion of periodontal dressing for 2 weeks; since local hygiene is suboptimal, the healing screw is placed after abutment and dressing removal (Fig.3).
Return to No Deviation 14 In Vitro Xin Wei, DDS, PhD, MS 1st edition 01/31/2020, last revision 07/17/2020