Objective: The aim of this study was to evaluate whether implant therapy or orthodontic space closure was the best treatment option for patients with missing maxillary lateral incisors.

Subjects and methods: The implant group (I group) consisted of 22 patients aged <26 years who had one or both maxillary lateral incisors substituted by a single implant-supported crown. The space-closure group (SC group) consisted of patients matched with I group patients based on diagnosis, gender, and number. Examinations were performed by one examiner and occurred at least 5 years after the prosthetic therapy or orthodontic treatment was finished. Clinical examination of the 44 patients involved assessing the aesthetics and gingival conditions of the implant-supported crown and the replacement canine, the occlusal morphology and the extraoral characteristics. Both the patient and examiner answered a question about their satisfaction with the aesthetic result.

Results: Of the 12 variables analysed by the examiner, one variable was significantly improved in the I group and five variables were improved in the SC group. There were no significant differences between the treatment groups for the remaining six variables. Gingival colour and crown length were better in the SC group, and crown colour was better in the I group. There were no significant differences between the groups with regards to the patient's and examiner's overall aesthetic satisfaction of the maxillary anterior teeth or between the patient's and examiner's opinion.

Conclusion: If both treatment alternatives are available, space closure is preferable.