Abstract
The purpose of the present study was to examine whether bacterial biofilm concerned with bacterial colonization and growth of subgingival plaque. We observed subgingival plaque of 95 severe adult periodontitis-affected teeth by scanning electron microscope. In the coronal one-third zone of subgingival plaque, cocci, rods and others established biofilm by glycocalyx-like structure. In the middle one-third zone, several kinds of bacterial species were coaggregated. Film-like microcolonies were also observed in this zone. We detected filamentous microorganisms appeared to come out from the film-like colonies, and observed holes which microorganisms had been passed through the colonies. In the apical one-third zone, several kinds of bacterial species aggregated by glycocalyx-like structures, which comprised netlike and mucoidal structure. In the “plaque-free zone”, two types of bacterial colonization were observed : bacterial cell wall directly contacted with the root surface, and microorganisms adhered to the root surface mediated by glycocalyx netlike materials. In this zone, five periodontal disease-associated bacteria, including Porphyromonas gingivalis, were detected using back-scattered electron imaging modes. The results of the present study suggested that bacterial biofilms were partially related to colonization and growth of subgingival plaque.
