Role of plaque in the aetiology of periodontal diseases
Since the classic experimental gingivitis study in 1965 (Loë et al., 1965), the aetiological role of dental plaque as the key agent in gingivitis has been acknowledged (Fig. 4.1). Nowadays, plaque is considered a good example of a biofilm (Marsh, 2005) and there are three different but interrelated hypotheses of its role in the aetiology of periodontal dieases (Loesche, 1976, 1979; Theilade, 1986; Marsh, 1991, 1994) (Fig. 4.2).
Dental plaque has been defined as a diverse community of microorganisms found on the tooth surface as a biofilm, embedded in an extracellular matrix of polymers of host and microbial origin. Biofilms are defined as matrix-embedded microbial populations, adhering to each other and/or to surfaces or interfaces (Marsh, 2005). The production of extracellular polymers forms a functional matrix.
|Stage||Plaque biofilm formation|
|1 Pellicle formation||Host and bacterial molecules, salivary glycoproteins, are adsorbed onto the tooth surface leading to acquired pellicle formation|