Depth of alveolar bone dehiscences in relation to gingival recessions.

Dehiscence depths were measured in vivo during surgical treatment of 113 teeth with gingival recession in 27 subjects. The average dehiscence depth determined was 5.43 mm with an average recession depth of 2.67 mm. Statistical evidence of a correlation between recession depth and dehiscence depth (average distance between lowest point of recession and dehiscence = 2.8 mm) leaves 16 affected teeth (n = 113) with a distance of 4 mm or more (up to a maximum of 7.5 mm) between the gingival margin and the alveolar crest (facial) unaccounted for. The significance of these deviations from mean values in the etiology and prognosis of recessions is discussed.