Relevance of Biofilm Models in Periodontal Research: From Static to Dynamic Systems

Abstract

Microbial biofilm modeling has improved in sophistication and scope, although only a limited number of standardized protocols are available. This review presents an example of a biofilm model, along with its evolution and application in studying periodontal and peri-implant diseases. In 2011, the ETEP (Etiology and Therapy of Periodontal and Peri-Implant Diseases) research group at the University Complutense of Madrid developed an in vitro biofilm static model using representative bacteria from the subgingival microbiota, demonstrating a pattern of bacterial colonization and maturation similar to in vivo subgingival biofilms. When the model and its methodology were standardized, the ETEP research group employed the validated in vitro biofilm model for testing in different applications. The evolution of this model is described in this manuscript, from the mere observation of biofilm growth and maturation on static models on hydroxyapatite or titanium discs, to the evaluation of the impact of dental implant surface composition and micro-structure using the dynamic biofilm model. This evolution was based on reproducing the ideal microenvironmental conditions for bacterial growth within a bioreactor and reaching the target surfaces using the fluid dynamics mimicking the salivary flow. The development of this relevant biofilm model has become a powerful tool to study the essential processes that regulate the formation and maturation of these important microbial communities, as well as their behavior when exposed to different antimicrobial compounds.

The Role of the Oral Microbiota Related to Periodontal Diseases in Anxiety, Mood and Trauma- and Stress-Related Disorders

“…These in vitro models are typically used to evaluate and identify putative molecular/cellular mechanisms that could be explored in relation to behavioral alterations in subsequent in vivo models (73). Another interesting approach is the development of in vitro periodontal biofilm models to test the antimicrobial/anti-inflammatory profile of different compounds and therapeutic strategies (74)(75)(76).…”

Antibacterial and Antiadhesion Effects of Psidium guajava Fractions on a Multispecies Biofilm Associated with Periodontitis

“…Based on these results, the mean OD of the samples treated with the methanol fraction of P. guajava showed a moderate decrease in adhesion to the biofilm, apparently representative of the antibacterial effect shown on S. gordonii, the microorganism responsible for biofilm adherence in periodontal biofilm models [32,33]. Despite the promising results, it should be emphasized that this experimental trial does not reflect the complex polymicrobial and environmental interactions present in the oral cavity.…”

Classic vs. Novel Antibacterial Approaches for Eradicating Dental Biofilm as Adjunct to Periodontal Debridement: An Evidence-Based Overview

“…To achieve this, many in vitro biofilm models have been introduced, mainly to investigate antimicrobial effect of eradicating periodontal pathogens on one hand, and to support the clinical application of these drugs on the other [ 62 , 63 , 64 ]. The evolution of biofilm modeling developed from mere observation of growth and maturation on static models such as hydroxyapatite or titanium disk to more advanced dynamic systems imitating the clinical environment has allowed a much closer insight into antimicrobial action [ 65 ].…”

“…Once more, this highlights the importance of using mechanical SD to disrupt biofilm and making limited use of these agents as adjuncts to mechanical SD, especially in deep and residual pockets [ 72 , 78 , 79 ]. Nevertheless, development of biofilm models is essential to assess growth and maturation of these microbial communities and their behavior during exposure to different antimicrobial agents, especially their sensitivity and resistance to the antimicrobial agent of interest [ 65 ].…”