Effect of hydrogen peroxide on developing plaque and gingivitis in man.

The present experiment was undertaken to assess the effect of hydrogen peroxide release during mouth rinsings on the composition of the microbiota of developing plaque in humans and the amount and pathogenecity of the plaque formed. The trial was designed as a double-blind crossover study of the effect of a mouthwash (Amosan) had a placebo rinse on the development of plaque and gingivitis in young adults. The active compound was available as a powder; the rinse consisted of 1.7 g powder dissolved in 30 ml hot tap water. Fourteen dental students participated in the trial. The students were examined during two consecutive periods, each consisting of one preparatory (during which active tooth cleaning measures were carefully practiced) and one main test period (during which mouth rinsings were the only plaque control measure). Each of the two test periods was initiated by a baseline examination following which the participants rinsed either with the active or the placebo mouthwash. The rinsings were performed immediately after breakfast, after lunch and after dinner. Measurements of Plaque and Gingival Index scores were performed 4, 7 and 14 days after the start of the no-toothbrushing period. Bacteria were sampled and examined after 7 and 14 days of trial. The results demonstrated that a mouthwash which released hydrogen peroxide effectively prevented the colonization of filaments, fusiforms, motile and curved rods as well as spirochetes in developing plaque. The mouthwash which was used as the only oral hygiene measure during a 2-week period furthermore markedly reduced the amount of plaque formed and significantly retarded gingivitis development. It is suggested that H202 released by mouthwashes during rinsing may prevent or retard the colonization and multiplication of anaerobic bacteria.