Purpose: To assess marginal bone loss (MBL) and implant stability when implant site preparation is performed with conventional drilling and the osteotome technique in the posterior maxilla. Materials and Methods: In total, 30 patients (mean age: 46.97 + 7.48 years) receiving 60 implants were enrolled in this study. In each patient, implant site preparation was done using either conventional drilling (conventional group; n = 30) or the osteotome technique (osteotome group; n = 30). The implant sites were further divided into groups based on the implant length used (implant length < 10 mm, implant length ≥ 10 mm). Marginal bone levels and implant stability quotient (ISQ) values were evaluated at the time of crown insertion and 1 year later. Independent t test and paired t test were used for intergroup and intragroup comparison, respectively. Results: The osteotome group showed statistically significant higher initial ISQ (ISQi) and final ISQ (ISQf) values (ISQi: 61 ± 3.6; ISQf: 64.08 ± 3.7) compared to the conventional group (ISQi: 58.01 ± 4.6; ISQf: 61.32 ± 4.8). Statistically significant higher mean MBL was noted in the conventional group (–0.33 ± 0.12 mm) compared to the osteotome group (–0.26 ± 0.10 mm). Higher MBL was noted in the osteotome group (–0.32 ± 0.09 mm) compared to the conventional group (–0.30 ± 0.14 mm) for implants shorter than 10 mm. For implants ≥ 10 mm in length, significantly higher MBL was noted in the conventional group (–0.37 ± 0.09 mm) compared to the osteotome group (–0.19 ± .06 mm). Conclusions: Osteotome technique could be used as an alternative to conventional drilling, especially when implants longer than 10 mm are planned in the posterior maxilla.