After 5 mm drill is used, the implant is seated deeper with insertion torque < 35 Ncm (Fig.6).  It suggests overprep.  Anyway, an immediate provisional is fabricated after placement of an abutment (7.8x4(3) mm).  After reline, the provisional fits well.  It has to be removed with forceps for occlusal adjustment.  Finally the abutment/implant complex turns in the socket with fingers.  The rotation/position of the complex is randomly adjusted.  When the provisional is cemented, it does not seat completely, but is stable.  If the implant osteointegrates, the provisional must play a role in stabilizing the implant.  Bone graft is placed in the gap prior to cementation (Fig.6 *).  Postop analysis of PAs in Fig.6,7 (1.5 month postop) shows that the peri-implant defect has been reduced in 1.5 months.  Immediately postop, the fourth coronal large thread is buried in the solid bone, whereas 1.5 months postop the third thread appears inside the base bone.  Bone density increases in the peri-implant space 16 months post cementation (Fig.10).

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Xin Wei, DDS, PhD, MS 1st edition 07/03/2017, last revision 11/09/2018