Influence of Insertion Torque on Marginal Bone Loss in Immediate Definitive Loading of Dental Implants: A Prospective Study

A bstract Aim: To evaluate the influence of insertion torque (IT) on marginal bone loss (MBL) in immediately loaded implants restored with definitive zirconia crowns. Methods: This prospective study included 26 adults receiving 48 implants placed using a flapless, digitally guided protocol. IT was categorized as moderate (40–50 Ncm) or high (55–70 Ncm). Standardized periapical radiographs were obtained at baseline and 12 months. MBL was measured mesially and distally after radiographic calibration. Nonparametric statistics and linear regression were used to assess associations. Results: All implants remained functional at 12 months (100% survival). The high‑torque group showed a significantly greater MBL than the moderate‑torque group (0.406 ± 0.25 mm vs. 0.056 ± 0.20 mm; median 0.40 mm [interquartile range (IQR): 0.20–0.75] vs. 0.00 mm [IQR: 0.00–0.10]; P < 0.001). The overall mean MBL was 0.12 ± 0.24 mm. Linear regression revealed a positive association between IT and MBL ( β = 0.019; 95% confidence interval: 0.011–0.027; R ² = 0.32; P < 0.001). Post hoc power analysis demonstrated 98.8% power. Conclusions: Higher IT values were associated with a statistically greater MBL, although overall bone loss remained clinically minimal. Immediate definitive loading with controlled torque appears reliable and biologically stable.