A total of 33 implant bodies (8 in the maxilla, 25 in the mandible) were inserted into the 27 participants (11 men, 16 women), with the average age of 54.6 ± 12.2 years (range, 32–78 years). The average IT value was 32.7 ± 9.2 N cm (32.5 ± 11.6 N cm in the maxilla, 32.8 ± 8.5 N cm in the mandible). The diameter of the implant body was 4.4 mm in 20 (60.6%) and 3.8 mm in 13 (39.4%), and the length of the implant body was 8.0 mm in 6 (18.2%), 10.0 mm in 19 (57.6%), and 12.0 mm in 8 (24.2%) (Table 1).

The measurement results of IT and ISQ are shown in Table 2. Due to the identification of mobility at 4 weeks postoperatively, No. 19 implant body (diameter, 4.4 mm; length, 12.0 mm) that had been inserted at the first molar position in the right mandible of a 32-year-old male patient was excluded from the evaluation. As a result, this study evaluated the 32 implant bodies (8 in the maxilla, 24 in the mandible) inserted into 26 participants. The survival rate of the implant bodies at the end of this study was 97% (maxilla, 100%; mandible, 96%).

The average ISQ values of all tested implant bodies increased through this study; moreover, all tested implant bodies indicated 60 or more ISQ value 6 weeks after the implant insertion. A significant difference was observed at 0 and ≥ 6 weeks (P < 0.01) (Fig. 3). No significant difference of average ISQ was found on the maxilla and mandible.

The inserted implant bodies were classified by IT value as the low IT group (< 30 N cm), the medium IT group (30–40 N cm), and the high IT group (≥ 40 N cm). Nine specimens were classified as the low IT group (3 in the maxilla, 6 in the mandible), 12 as the medium IT group (1 in the maxilla, 11 in the mandible), and 11 as the high IT group (4 in the maxilla, 7 in the mandible) (Fig. 4). There was no difference between the maxilla and the mandible in the average value of the IT (maxilla 32.5 ± 11.6 N cm, mandible 32.9 ± 8.7 N cm).