Caroliene Meijndert

67 Bone level tapered implants in the maxillary aesthetic zone Implant survival rate No implants were lost during the follow-up, resulting in a 100% implant survival rate. ( Table 2 ) Marginal bone level change Figure 1 shows the radiographic changes from before the treatment to 12 months after definitive crown placement. Implant survival rates and marginal bone level changes are depicted in table 2 . The mean marginal bone level changed significantly in the first 7 months after implant placement. Thereafter only little, non-significant change occurred. The peri-implant bone level changes were not normally distributed, so it is appropriate to note the medians and IQR but, to give more insight into the actual change, the bone level changes are also depicted as mean±SD. Table 2. Survival rate (%), implant stability quotient (ISQ) and bone level change (in mm) from time of implant placement to 12 months after definitive crown placement, measured in mm. n=30. Survival rate 100% Implant stability ISQ at implant placement at definitive crown placement p * 73 [68;76] 79 [77;81] <0.00 Bone level change (mean±SD) T 0 -T 1 p ** T 0 -T 12 p ** T 1 -T 12 p ** Mesial -0.48±1.13 0 .001 -0.54±1.20 0.000 -0 .09±0.15 0.68 Distal -0.55±0.98 0.000 -0.56±0.98 0.002 -0.06±0.15 0.16 Mean of mesial+distal -0.53±1.02 0.000 -0.51±1.06 0.000 -0.07±0.10 0.66 * Wilcoxson signed rank test. A bonferroni core ** The threshold for significance is p<0.017 due to the Bonferroni correction T 0  = time of implant placement. T 1 = one month after definitive crown placement (7 months after implant placement). T 12 = 12 months after definitive crown placement (18 months after implant placement) Clinical parameters The bleeding index, gingiva index and mean probing depth scores from the 12 month evaluation are depicted in Table 3 . Therewere no significant differences between T 1 and T 12 . 4