The use of rodent models to investigate host–bacteria interactions related to periodontal diseases

Abstract

Even though animal models have limitations they are often superior to in vitro or clinical studies in addressing mechanistic questions and serve as an essential link between hypotheses and human patients. Periodontal disease can be viewed as a process that involves four major stages: bacterial colonization, invasion, induction of a destructive host response in connective tissue and a repair process that reduces the extent of tissue breakdown. Animal studies should be evaluated in terms of their capacity to test specific hypotheses rather than their fidelity to all aspects of periodontal disease initiation and progression. Thus, each of the models described below can be adapted to test discrete components of these four major steps, but not all of them. This review describes five different animal models that are appropriate for examining components of host-bacteria interactions that can lead to breakdown of hard and soft connective tissue or conditions that limit its repair as follows: the mouse calvarial model, murine oral gavage models with or without adoptive transfer of human lymphocytes, rat ligature model and rat Aggregatibacter actinomycetemcomitans feeding model.

Ligature‐associated bacterial profiles are linked to type 2 diabetes mellitus in a rat model and influenced by antibody treatment against TNF‐α or RAGE

“…Experimental PD in rats is based upon subgingival placement of ligatures that facilitate accumulation of bacteria, which in turn initiate periodontal inflammation (Graves, Fine, Teng, Van Dyke, & Hajishengallis, 2008; Pontes Andersen et al, 2007). Thus, subgingival placement of the ligature increases biofilm formation, and a direct comparison between ligature‐induced PD in rats and naturally occurring PD in humans is not possible (Graves et al, 2008).…”

“…Experimental PD in rats is based upon subgingival placement of ligatures that facilitate accumulation of bacteria, which in turn initiate periodontal inflammation (Graves, Fine, Teng, Van Dyke, & Hajishengallis, 2008; Pontes Andersen et al, 2007). Thus, subgingival placement of the ligature increases biofilm formation, and a direct comparison between ligature‐induced PD in rats and naturally occurring PD in humans is not possible (Graves et al, 2008). It is, however, interesting that while trauma from the ligature obviously play a role in periodontal disease progression in the PD rat model, a study in germfree rats showed that no bone loss occurred in the absence of biofilm accumulation (Rovin, Costich, & Gordon, 1966).…”

Oral health in geroscience: animal models and the aging oral cavity

“…The periodontal anatomy of rodent molars is similar to humans, and for this reason, mice, in particular, have been proven useful for investigating a variety of mechanisms underlying oral diseases (Struillou et al, 2010;Yamasaki et al, 1979). For instance, relationships between immune function, microbial changes within the oral cavity, and inflammation have been established through studies performed in rodent models (Struillou et al, 2010;Oz & Puleo, 2011a;Graves et al, 2008;Polak et al, 2009). In contrast, one way that rodents differ substantially from humans is that their incisors lack a root structure and grow continuously throughout life, with only the front of the incisors having enamel.…”

Periostin-deficient mice, a relevant animal model to investigate periodontitis or not?

“…10,11 Oral infection is achieved either by oral gavage or by local application using silk ligatures retentive of bacterial plaque around a first maxillary or mandibular molar, both models were then subjected to a wash-out period of 10 days with antibiotic treatment. Typically, gavage of a bacterial strain is orally administered in a 2% carboxymethylcellulose soft diet containing bacteria three times per week for at least 4 weeks.…”