A 5-year prospective study on single immediate implants in the aesthetic zone.

Abstract

There is a paucity of long-term data on soft tissue aesthetics of single immediate implants. The objective of this study was to evaluate the 5-year clinical and aesthetic outcome of this treatment concept. Twenty-two periodontally healthy patients (12 men, 10 women; mean age 50) with low risk for aesthetic complications (thick gingival biotype, intact buccal bone wall, both neighbouring teeth present) were consecutively treated with a single immediate implant in the aesthetic zone (15-25). Flapless surgery was performed and the gap between the implant and buccal bone wall was systematically filled with bovine bone particles. Implants were immediately non-functionally loaded with a screw-retained provisional crown. Cases demonstrating major alveolar process changes and/or advanced mid-facial recession (>1mm) at 3months were additionally treated with a connective tissue graft (CTG). Permanent crowns were installed at 6months. The clinical and aesthetic results at 5years were compared to those obtained at 1 year. Seventeen patients attended the 5-year re-assessment, of whom five had been treated with a CTG for early aesthetic complications. There was one early implant failure and one complication after 1 year (porcelain chipping). Mean marginal bone loss was 0.12mm at 1 year and 0.19mm at 5years (p=0.595) with the moment of implant installation as baseline. Papilla height increased between 1 and 5years (p≤0.007), whereas mid-facial contour (p=0.005) and alveolar process deficiency (p=0.008) deteriorated. Mean mid-facial recession was on average 0.28mm (SD 0.48) at 1 year and 0.53mm (SD 0.53) at 5years (p=0.072) with the preoperative status as baseline. Three implants demonstrated advanced mid-facial recession (>1mm) at 5years. All three were in a central incisor position and none had been treated with a CTG. Thus, 8/17 implants showed aesthetic complications (five early and three late aesthetic complications). Implants in a lateral incisor position showed stable soft tissue levels. The pink aesthetic score was on average 12.15 at 1 year and 11.18 at 5years (p=0.030). Single immediate implants showed high implant survival and limited marginal bone loss in the long term. However, mid-facial recession, mid-facial contour and alveolar process deficiency deteriorated after 1year. With an aesthetic complication rate of 8/17 in well-selected patients who had been treated by experienced clinicians, type I placement may not be recommended for daily practice.