A preliminary report from on physiological bone remodeling on KS versus TSIII implants for molar rehabilitations: a split-mouth, multicenter randomized controlled trial

Objective: To compare the clinical and radiographic outcomes of two implant systems with different implant–abutment connection designs—KS BA (4.0 mm diameter, 15° internal taper) and TS III BA (4.5 mm diameter, 11° internal connection)—used for molar rehabilitation. Materials and Methods: This multicenter, split-mouth, randomized controlled trial involved 42 patients, each receiving one KS and one TSIII implant. Inclusion criteria required healed posterior sites suitable for implants at least 8.5 mm long. Surgeries followed standardized protocols, and patients were rehabilitated with monolithic zirconia crowns bonded to titanium bases. Clinical follow-up was conducted at 6 months after prosthesis delivery. Primary outcomes were implant and prosthesis survival rates and any complications. Marginal bone levels (MBL) were measured radiographically at implant placement, prosthesis delivery, and 6-month follow-up. Patient satisfaction were also recorded. Results: A total of 87 implants (44 KS and 43 TSIII) were placed. At the time of analysis, 27 patients with 53 implants completed the 6-month follow-up. No implant or prosthesis failures and no complications were observed. At prosthesis delivery, mean MBL was 0.32 ± 0.27 mm for TSIII and 0.18 ± 0.32 mm for KS implants (P = 0.029). At 6 months, MBL increased to 0.34 ± 0.27 mm (TSIII) and 0.21 ± 0.32 mm (KS), with a statistically significant difference favoring the KS group (P = 0.034). All patients reported full satisfaction with functional and aesthetic outcomes. Conclusion: The KS implant system demonstrated significantly less marginal bone loss than the TSIII system, despite its narrower diameter. These preliminary findings support the clinical efficacy and mechanical reliability of the KS implant for molar restoration, suggesting it as a viable alternative in posterior sites, especially where bone volume is limited.