[Long-term study on the effects of the width of keratinized gingiva on the localization of the gingival margin].

In a 5-year longitudinal study we assessed the amount and frequency of gingival recessions in relation to the width of the keratinized gingiva and the already existing recessions in two groups (each n = 15). Group I (dental students) had nearly no recessions and group II (patients) had exposed roots on 24% of their teeth. In both groups there existed no correlation between the width of the keratinized gingiva or, respectively the existing recessions and the recessions occurring. Only 36 sites had a recession greater than or equal to 1 mm, these were accumulated in just a few probands.