2.9. Statistical Analysis
Statistical analysis was performed by using SPSS 20.0 software. A one-sample Kolmogorov–Smirnov test was used to test the normality of the MBL change distribution. An Kaplan–Meier curves were utilized for the survival analysis (MDI failures and compromised survivals were counted as one category, while successful implants and satisfactory survivals were counted together as another category). A comparison of the 4-MDI and 3-MDI groups was made using the Log-rank Mantel–Cox test.