Alterations in gingival dimensions following rapid canine retraction using dentoalveolar distraction osteogenesis

The aim of this clinical prospective study was to evaluate the alterations that occurred in the gingival dimensions of canine teeth following dentoalveolar distraction (DAD) during a 12 month follow-up period.The study sample comprised 36 maxillary canines of 18 growing or adult subjects with a mean age of 16.94 years (13.08-25.58 years) at the start of treatment. Full retraction of the canines was achieved in 10.36 +/- 1.93 days (range 8-14 days) at a rate of 0.8 mm/day using a custom-made intraoral rigid tooth-borne distraction device. Before surgery (pre-DAD), immediately after removal of the device (post-DAD), and at 1, 6, and 12 months post-DAD, the plaque index (PI), gingival index (GI), pocket depth (PD) and width of keratinized gingiva were recorded and the width of attached gingiva was calculated. The alterations in clinical measurements among different evaluation periods were analysed by Friedman and repeated measure ANOVA tests. There were significant differences between pre- and post-DAD for PD measurements for all sites, with the highest at the distal site. The palatal sites likewise showed significant differences at the 1, 6, and 12 month follow-up periods compared with the post-DAD period. The buccal sites showed no significant changes at any time point. The width of keratinized gingiva also showed no significant change during the follow-up period, while the width of attached gingiva was significant only between the pre- and post-DAD periods (P < 0.01). On the basis of the above findings, it could be concluded that DAD is an innovative technique with no unfavourable long-term effects on the gingival tissues of rapidly retracted canine teeth.