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1 - y e a r s t u d y o f n o n s u b m e r g e d i m p l a n t s Figs. 2A–C A Figs. 2D–F D Figs. 2G & H G C F B E H Figs. 2A–H Maxillary left lateral incisor that had previously undergone an apicoectomy. The tooth presented high-grade mobility and extraction was scheduled. (A) Pre-extraction vestibular view. Atraumatic extraction was performed, as well as adequate alveolar socket debridement. (B) Post- extraction view. A Prama implant was placed nonsub- merged according to the manufacturer’s instructions; (C) vestibular and (D) occlusal views. After 3 months, impressions were taken (D) and an abutment was fixed (E). No second surgeries were performed to expose the implant neck. A provisional crown was cemented free from tissue compression (F) and a metal–ceramic crown was later cemented (G). bone loss (mean MBL: -0.30 ± 0.78 mm). Considering all of the implants placed and eval- uated in the present study, a mean MBL of -0.37 ± 0.41 mm was observed at T12, in agree- ment with standard success criteria and the previous recent study.32 Concerning MBL in relation to placement timing groups (immediate, early and delayed), delayed implants showed greater bone loss (0.61 ± 0.38 mm) at 12 months, while early and immediate implants showed limited bone loss (MBL: 0.25 ± 0.45 mm and 0.34 ± 0.04 mm, respectively). These results were in accordance with another previous published study, which investigated implants with the same surface, but a different neck morphology (tulip-shaped, platform-switched implants).33 Bone remodel- ing procedures are probably different in mature (delayed group) or immature bone (early and immediate group), as recently shown in several in vivo animal studies that tested the ZrTi implant surface micromorphology used in Prama implants.34, 35 In all of the patients, periimplant gingival biotype was evaluated after 12 months from implant insertion. Thin gingival biotype demon- strated greater bone loss values at 12 months (P = 0.008). This is in accordance with the find- ings of a recent study with a different bone level implant.36 Considering all of the parameters evaluated in the statistical analysis, gingival biotype was found to greatly affect MBL.37 Berglundh and Lindhe demonstrated in an animal study that a thin gingival biotype may affect crestal bone stability.38 Thus, also for this type of implant, postoperative gingival biotype may be considered one of the most important clinical parameters that may affect MBL at least after 12 months from placement. Soft-tissue parameters evidenced an improvement from 6 to 12 months, showing a soft-tissue maturation over time. The mean PES was 11.09 at 6 months (2 months from definitive loading) and improved at the 12-month follow-up, showing a mean value of 11.95. This confirms that soft-tissue modifications occur during the first months of loading. Similar PES values are reported in the literature. In a 12-month clinical study, the PES of 2 different implant treatment strategies was evaluated (immediate implants versus conven- tional loading). Their 12-month mean values were 10.33 and 10.35, respectively.1 Interestingly, in our study, a high prevalence of the maximum soft-tissue color score was found (65.51% at 6 months and 77.28% at 12 months), despite the presence of an unfavor- able preoperative score (approximately a quarter of the preoperative soft-tissue color presented a 0 score). The yellow Prama hyperbolic neck, together with the presence of a thick gingival Journal of Oral Science & Rehabilitation Volume 3 | Issue 4/2017 39