Several factors may affect the outcome of the orthodontic/surgical modality for the resolution of impacted central incisors, but particularly the manner in which the impacted tooth is exposed. The present study aimed to evaluate the post-retention clinical appearance and periodontal status of impacted maxillary central incisors which were exposed and aligned with an open-eruption surgical-orthodontic technique. Twelve subjects (four males, eight females), aged 22 years (range 15-38 years), previously treated for a unilateral impacted central incisor (ICI), were examined 10 years (range 3-25 years) post-retention. A split-mouth method was used for the comparison with the unaffected side. One treated central incisor exfoliated 10 years post-retention, thus the results were based on the remaining 11 patients. Statistically significant differences were found between the affected and control incisors in most of the periodontal parameters measured, although some were small and of minimal clinical importance. The increase in the mesio-labial pocket depth was associated with a highly significant 10 per cent reduction in bone level at this site (P= 0.007). A highly statistically significant increase in crown length (P < 0.001) and a reduction in the width of the attached gingiva (P = 0.005) were seen in these previously impacted teeth. An abnormal gingival contour was present in eight treated incisors and positional relapse in five cases. It is concluded that the convenience of the open-eruption technique must be weighed against the long-term negative aesthetic and periodontal effects on the treated tooth, although the findings of this study should be viewed with caution due to the limited sample size.