A short (11 mm in Fig.4) or long (14 mm in Fig.5) tissue-level implant is placed without or with sinus lift.  The implant could be as large as 7 mm (Fig.5).  It should be according to the width of the alveolus clinically.

Upper 1st Molar Septum Placement

Xin Wei, DDS, PhD, MS 1st edition 04/25/2015, last revision 04/25/2015