Caroliene Meijndert

92 Chapter 5 significant ridge alterations and resorption of the applied augmentation (Buser et al., 2004; Chappuis et al., 2017). A short healing time gives the risk of placing the implant in soft bone, thus not reaching enough initial implant stability. In the present study, it was chosen to have a healing time of 3 months after alveolar ridge surgery, following the protocol of previous studies on alveolar ridge preservation at the same department in which good results were reached (Slagter et al., 2016; Zuiderveld et al., 2019). The thickness of labial bone wall at implant placement was insufficient in 10 cases (33.3%) and had to be augmented to achieve a labial bone wall thickness of at least 2 mm. The insufficient thickness could not be attributed to type of bone used for the alveolar ridge preservation, as the origin of augmented bone was evenly distributed between maxillary tuberosity and retromolar area. Apparently, placement of tapered implants in sites in which alveolar ridge preservation has been executed does not prevent the need for an extra bone augmentation at the labial side of the implant in all cases. This was also seen in other studies with alveolar ridge preservation in the aesthetic region. In Zuiderveld et al. (2019) in 45% of the cases an extra bone augmentation procedure was needed and in Lai et al. (2020) this was the case in 26.3%. In the absence of studies with the same implant brand and design, comparisons can best be made with other implant systems with a tapered design, applied in the aesthetic region. Eghbali et al. (2018) presented 1 year results of alveolar ridge preservation and connective tissue grafts. In this study the implants (NobelActive implant system, Nobel Biocare AB, Goteborg, Sweden) were placed 4 months after alveolar ridge preservation and a provisional restoration combined with a connective tissue grafts were performed 3 months later. Implant survival after one year was 100%. Favourable clinical and aesthetic outcome were reported. The mean marginal bone loss was 0.53 mm and the mid-facial recession amounted 0.05 mm at 1 year. In the Zuiderveld et al. (2019) study, the NobelReplace CC implant system (Nobel Biocare AB, Goteborg, Sweden) was used in the maxillary aesthetic region, again after ridge preservation. After a one-year follow-up, the implant survival was 100%, and the change in marginal bone level was +0.03±0.4 mm mesially and +0.13±0.5 mm distally. These changes are minor and are comparable to those in the present study. The aesthetic outcome is of particular interest for restorations in the aesthetic zone. Aesthetics can be evaluated by professionals with the PES/WES score (Belser et al., 2009) and by patients with questionnaires (Kanatas & Rogers, 2010). Our median PES/ WES score was 6/8 after one year. This is in line with Zuiderveld et al. (2019) who noted a mean PES/WES score of 6.6/8.7 after one year. The present study’s overall patient’s satisfaction score was also very much alike with the satisfaction scores mentioned by