Effect of Dental Implant Design on Stability During Early Healing: A Randomised Controlled Trial

Abstract

Objective: To evaluate the stability changes of two dental implant designs over 6 weeks of healing. Materials and Methods: Patients with edentulous sites who had undergone tooth extraction more than 2 months earlier were randomly assigned to receive either tapered (BLX) or cylindrical (BL) implants (SLA/Roxolid, Straumann, Switzerland). Implant stability was assessed via the maximum insertion torque (MIT), implant stability tests (ISTs) and implant stability quotient (ISQ). ISTs were conducted immediately (T1), on Day 2 (T2) and weekly for 6 weeks (T3–T8); ISQ was measured at T1 and T8. Results: Eighty-five implants were placed in 66 patients (45 BLX, 40 BL). BLX implants showed a significantly higher mean MIT (42.35 ± 13.43 N·cm) than BL implants (30.63 ± 6.01 N·cm, p < 0.001). Both designs demonstrated similar stability trends. At T8, BL implants had significantly higher ISQ and IST values (75.21 ± 0.93 and 79.69 ± 1.11) than BLX (72.23 ± 0.88 and 76.06 ± 1.04, p = 0.02), while there were no differences at earlier time points. A moderate positive correlation was observed between ISQ and IST (r = 0.56, p < 0.001). Conclusion: Both implant designs provided high and lasting stability during early healing, establishing their suitability for various prosthetic loading protocols. Trial Registration: Thai Clinical Trials Registry (TCTR) TCTR20210628006 (https://www.thaiclinicaltrials.org/export/pdf/TCTR20210628006) and TCTR 20230826014 (https://www.thaiclinicaltrials.org/export/pdf/TCTR20230826014).