Increasing oral PMN during experimental gingivitis and its reversal by prophylaxis

This investigation evaluated clinical parameters and the levels of polymorphonuclear leukocytes [PMN] collected in an oral rinse amongst subjects who refrained from dental hygiene for a period of 12 days.

Study enrolled consenting adults and assigned to a non-prophy group [n = 16] and a separate prophy group [n = 27]. Both groups underwent clinical evaluations and sampling for PMN at baseline and on days 3,6,9 and 12 of study initiation. The prophy group underwent supragingival prophylaxis at the conclusion of the no-hygiene phase and recalled for a final clinical evaluation and PMN assessment 1 week later.

Progressive increases in oral PMN were noted due to abstinence from oral hygiene (p < 0.05). Subjects registered PMN increases ranging from 20% recorded three days following abstinence of hygiene to the highest value of 298% at the 12-day evaluation (p < 0.05). One week after prophylaxis, average PMN scores were 22% lower than baseline (p < 0.05). Abstinence from dental hygiene led to progressive increases in clinical parameters for dental plaque, gingival inflammation and bleeding. Dental plaque, gingival index and gingival bleeding scores recorded increases of 59%, 64% and 126% respectively at the conclusion of the no-hygiene phase. Prophylaxis resulted in marked reductions in all clinical parameters.

Abstinence from dental hygiene corresponded with increasing scores for dental plaque, gingival inflammation and bleeding in conjunction with increasing oral PMN. These effects were irrespective of age or gender and were reversed by supragingival prophylaxis.