The reversal of localized experimental gingivitis

Twenty dental students randomly divided into four groups of five participated in this trial. Three weeks of supervised oral hygiene preceded the study in order to ensure a optimum state of gingival health. The gingival condition was assessed by means of the Gingival Index and measurements of gingival exudate. Plaque accumulation was assessed by means of the Plaque Index. Using plaque-guards, two 21-day periods were alllowed for the induction of localized experimental gingivitis around a lateral incisor and adjacent canine in each jaw. The contralateral areas served as controls. Habitual oral hygiene procedures were maintained in all other areas of the mouth throughout the experimental periods. Following 21 days of localized plaque accumulation in the mandibular experimental areas, mechanical toothcleaning procedures were introduced at intervals of once a day (Group A), once every second day (Group B), once every third day (Group C) and once every fourth day (Group D). Groups A and B regained gingival health in 10 days. The experiment was then repeated in the maxillary experimental areas. Group A, rinsing once daily with chlorhexidine solution regained gingival health in 4 days. The results obtained in the localized experimental gingivitis model were similar to those reported when totally withdrawing oral hygiene.