Evaluation of thin-threaded implants primary stability in type IV bone right after maxillary sinus floor elevation: A human cadaver study.

Purpose: The bone-implant interface plays a crucial role in obtaining sufficient primary stability for dental implants in weak bone supports. The aim of this human cadaver study was to evaluate the primary stability of new thin-threaded implants when placed in type IV bone right after maxillary sinus floor elevation.

Materials And Methods: The study followed the CACTUS (ChAracteristics of Cadaver Training and sUrgical Studies) guidelines. Twenty-four edentulous maxillary posterior zones with type IV bone and a residual bone height of 4 mm were selected using computed tomography scans. First, an osteotome sinus floor elevation was performed (C.M.C Tech, IBS IMPLANT, Daejeon, South Korea). Implants with thin threads (MagiCore, IBS IMPLANT, Daejeon, South Korea) were placed simultaneously. Samples were divided into two groups: Group 1 (G1): 11 mm-long implants with an elevation of 8 mm; Group 2 (G2): 7 mm-long implants with an elevation of 4 mm. Primary stability was assessed using resonance frequency analysis (RFA).

Results: The average primary stability values in the mesiodistal (MD) direction were 45.67 ± 3.09 Implant Stability Quotient (ISQ) for G1 and 38.76 ± 16.94 ISQ for G2, and in the buccolingual direction were 43.33 ± 13.23 ISQ for G1 and 38.47 ± 16.14 ISQ for G2.

Conclusions: The primary stability of the thin-threaded implants was compatible with clinical osseointegration in sinus sites with limited bone contact area in both experimental situations. Clinical studies are needed to confirm these encouraging results.