Caroliene Meijndert

53 Performance of bone level implants with conical connections in the anterior maxilla Discussion Bone level implants with conical connection presented with a good clinical performance in the maxillary anterior region and a high patients satisfaction after 5 years in function. Implant survival was 100% and crown survival 98%. Irrespective of the need for a pre- implant surgical bone augmentation procedure, the change in bone level was minor in both subgroups. The null-hypothesis that there was no difference in change of bone level between the subgroups could not be rejected. Regarding the 5-year results of solitary bone level implants with a conical implant-abutment connection in the healed anterior maxilla, the outcomes of the studied implant type are in line with the results from other studies. The mean marginal bone level change of the authors who conducted comparable studies all remained substantially under the 0.5 mm bone loss. (Palmer et al., 2000; Gotfredsen, 2004; Pieri et al., 2013; Berberi et al., 2014; Cooper et al., 2014). Although a different implant system was used in the afore mentioned studies (Astra Tech Implant System), bone level change reported in the present study is similar to results from the other cited studies mentioned previously. A statistically significant difference was found between the pocket probing depths of the augmented group (3.25 [2.50 ; 3.25]) and the non-augmented group (2.50 [2.25 ; 3.00]; p=0.04). A possible explanation could be that inherent to a bone augmentation procedure soft tissues heal differently on a surface of a newly applied material, being a mixture of autologous bone and a bone substitute. It must be noted, however, that the difference in probing depth is very small and not clinically relevant. The clinical parameters in our study - pocket probing depth, plaque score, bleeding score and Gingiva Index - are comparable to those reported by Gotfredsen, Pieri and Cooper (Gotfredsen, 2004; Pieri et al., 2013; Cooper et al., 2014). In the present study, no incidences were associated with the implant-abutment connection. Previous studies have reported soft tissue complications associated with abutment screw loosening (Krishnan et al., 2014; Goodacre et al., 2018; Pjetursson et al., 2018). The absence of connection-related complications in this study suggests a strong fixation and tight seal of a conical connection. This was also appointed by Palmer and co-workers (Palmer et al., 2000). PES and WES scored high and the level of acceptance (6 or higher) was exceeded in 74% for PES and 92% for WES. During the T60 assessment of the WES, the aesthetic outcome of 56% (n=28 of 50) of the patients was assessed as poor because the incisal edge was in infraposition compared to the contra-lateral tooth. At the 1-year follow- up, only 26% (n=16 of 60) patients got a poor judgement on this item. Having the same 3