Effect of an enamel matrix protein (Emdogain®) on ex vivo dental plaque vitality

Background: A common clinical observation following surgical periodontal therapy with an enamel matrix derivative (Emdogain((R))) is the improved healing of the Soft tissues and the limited inflammation of the operated areas. These clinical observations are empirical and difficult to explain. One of the factors influencing the early wound healing might be a potential antimicrobial effect of Emdogain((R)). Aim: To investigate the effect of Emdogain((R)) on the vitality of ex vivo supragingival dental plaque and to compare this effect to that of a standard 0.2% chlorhexidine solution. Materials and Methods: 24 patients suffering from adult periodontitis were included in the study. At the beginning of the experiment, all participants were given a professional tooth cleaning. For the following 4 days, they had to refrain from any kind of oral hygiene measures. At day 5, from each of the volunteers, a voluminous plaque biofilm sample was taken with a sterile curette from the vestibular surfaces of the Ist lower molars and divided into 5 equal parts. Each part was mounted with 5 pl of the following solutions: (1) NaCl, (2) enamel matrix derivative dissolved in water (EMD), (3) enamel matrix derivative dissolved in the vehicle (Emdogain((R))), (4) vehicle (propylene glycol alginate, PGA), (5) 0.2% chlorhexidine digluconate (CHX). After a reaction time of 2 min the test solutions were sucked off, and subsequently the biofilm was stained with a fluorescence dye. The vitality of the plaque flora after the treatments was evaluated under the fluorescence microscope (VF%). Results: Plaque samples treated with NaCl showed a mean vitality of 76.8 +/-8%. The EMD, Emdogain((R)), PGA and CHX showed VF values of 54.4 +/-9.2, 21.4 +/- 10.6%, 19.6 +/- 11.6% and 32.3 +/- 11.8%, respectively. Emdogain((R)), PGA and CHX showed statistically highly significant reductions (p <0.0001) in terms of bacteria vitality when compared to water (negative control) and EMD. Both Emdogain((R)) and PGA were found to be statistically significantly different compared to CHX (p <0.001) (positive control). Conclusion: The results of this study indicate that Emdogain((R)) might have an antibacterial effect on the vitality of the ex. vivo supragingival dental plaque flora.