Purpose: The aim of this study was to evaluate interproximal papillae and clinical crown height following the placement of single-tooth implants according to early and delayed protocols. Materials and Methods: Forty-five patients were randomly allocated to either the "early" group or the "delayed" group. They were treated with a single-tooth acid-etched Osseotite implant in the maxillary or mandibular anterior or premolar region an average of 10 days (in the case of early placement) or 3 months (in the case of delayed placement) following tooth extraction. Interproximal papilla dimensions and clinical crown height were evaluated using a score index in 39 patients who attended a follow-up visit 16 to 18 months after prosthesis delivery. The patients were evaluated in photographs taken 1 week after crown placement (baseline) and approximately 1.5 years after crown placement (follow-up). Results: It was demonstrated by logistic regression the risk of presenting no papilla or a negative papilla was 7 times greater at baseline for delayed cases than for early cases (33% versus 8%). However, the soft tissue fill in the proximal spaces improved significantly from baseline to the 1.5-year follow-up in both groups, with no significant difference between the groups found at follow-up. The papilla height almost 2 years after implant placement was inversely correlated with patient age. The clinical crown height was acceptable in significantly more cases in the early group than in the delayed group at follow-up. Half of the crowns in the delayed group exhibited an inappropriate height; of these, almost two thirds were assessed to be too short. Discussion and Conclusion: Early placement of single-tooth implants may be preferable to delayed implant placement technique in terms of early generation of interproximal papillae and the achievement of an appropriate clinical crown height, but no difference in papilla dimensions was seen at 1.5 years after seating of the implant crown. Palabras clave: delayed implant placement, dental implants, early implant placement, esthetics of dental prostheses, mucosa