This case concerns a patient with a history of controlled moderate periodontitis and generalised bone loss, who presented with advanced tooth mobility affecting molars 27 and 28; extraction was therefore indicated. Following extraction of both teeth, cone-beam computed tomography (CBCT) showed severe vertical atrophy in the posterior region of the second quadrant, with a residual bone height of approximately 2.5 mm in the most distal region and 3.4 mm in the mesial region. Given the limited bone availability, restoration was planned using two 4.5 mm ultra-short implants combined with transcrestal sinus elevation, avoiding more complex reconstructive procedures. A 4.75 mm diameter was selected for the distal implant, which was positioned towards the region with greater bone availability near the buccal cortical plate, with the aim of achieving primary stability from the limited residual bone volume. The implant site was prepared using biological drilling at low speed without irrigation, and sinus membrane elevation was completed via a crestal approach.

The six-month follow-up CT scan showed favourable bone changes around the implant, with an increase in bone height in the apical and distal regions. Comparison of the CT slices showed that the ridge height had increased from approximately 2.3 mm before treatment to 7 mm after the procedure and healing period.

A second 4.5 mm implant was subsequently placed in a more mesial position in the same quadrant, where the residual bone height was also less than 4 mm. Both implants were restored as a splinted unit using a screw-retained prosthesis on transepithelial abutments. A provisional restoration was initially used to establish stable occlusion, followed by fabrication of the definitive prosthesis.