Experimental gingivitis in patients with altered passive eruption: A case control study. Clinical and histological evaluation

Background: Passive eruption is a process by which the epithelial attachment of the gingival tissue retracts from the enamel portion of the crown onto the root into adult position just apical to the CEJ allowing for a fibrous connective tissue attachment at the base of the sulcus (the biological width). Authors indicate that an excess of gum on the tooth impedes oral hygiene and can cause disease especially in individuals who already have a high predisposition to periodontitis. Aim: Despite the fact that many authors suggest that the patients with altered passive eruption are more susceptible to gingivitis and periodontitis due to the excess of gingiva, which impedes the correct oral hygiene procedure, there is to-date no clinical study confirming this assumption. The aim of the present study is therefore to examine the onset, progress and the healing of experimental gingivitis in patients with altered passive eruption when compared to patients with normal gingival anatomy. Material and Methods: 9 patients with altered passive eruption for the test group and 9 patients with normal anatomy of gingival tissues as a control group were selected for the study. The clinical parameters have been compared also intrapatiently, due to fact that the patient developed an experimental gingivitis only in one selected side(test) of maxillary arch, another side has been considered as a control. Results: On day 7 (T1), all clinical parameters related to gingival status were similarly low in both test and control groups. On day 21 (T3), at the time of maximum amount of plaque accumulation, there was a statistically significant difference between two groups in the gingival inflammatory indices. Thus, AngBS(Angulated bleeding score) on day 21 (T3) was 1.78 ± 0.44 in test and 0.67 ± 0.50 in control groups (p=0.002); and MGI(modified gingival index) was 2.78 ± 0.44 in test and 1.33 ± 0.50 in control groups (p=0.002). At the end (T6) of experimental gingivitis, the difference in the inflammatory indices was insignificant, but despite this, some patents in the test group still had signs of gingivitis, while the patients from control group were completely healthy related to gingival status. Conclusion: Notwithstanding, even if gingivitis in patients with altered passive eruption is developed much more rapidly, thorough home oral hygiene and plaque control conduces to complete clinical recovery. In spite of the clinical convalescence, however, some patients with APE show microscopic signs of gingival inflammation. Further studies with a large number of patients are required to confirm the correlation between altered passive eruption and periodontal diseases, and to determine how its surgical correction can affect this relationship.