title: Long-term evaluation of oral gavage with periodontopathogens or ligature induction of experimental periodontal disease in mice.
abstract: OBJECTIVE
  To evaluate in long-term periods the destruction of periodontal tissues and bacterial colonization induced by oral gavage with periodontopathogens or ligature experimental periodontal disease models.
  
  
  METHODS
  Forty-eight C57BL/6 J mice were divided into four groups: group C: negative control; group L: ligature; group G-Pg: oral gavage with Porphyromonas gingivalis; and group G-PgFn: oral gavage with Porphyromonas gingivalis associated with Fusobacterium nucleatum. Mice were infected by oral gavage five times in 2-day intervals. After 45 and 60 days, animals were sacrificed and the immune-inflammatory response in the periodontal tissue was assessed by stereometric analysis. The alveolar bone loss was evaluated by live microcomputed tomography and histometric analysis. qPCR was used to confirm the bacterial colonization in all the groups. Data were analyzed using the Kruskal-Wallis, Wilcoxon, and ANOVA tests, at 5 % of significance level.
  
  
  RESULTS
  Ligature model induced inflammation and bone resorption characterized by increased number of inflammatory cells and decreased number of fibroblasts, followed by advanced alveolar bone loss at 45 and 60 days (p < 0.05). Bacterial colonization in groups G-Pg and G-PgFn was confirmed by qPCR but inflammation and bone resorption were not observed (p < 0.05).
  
  
  CONCLUSIONS
  The ligature model but not the oral gavage models were effective to induce inflammation and bone loss in long-term periods. Pg colonization was observed in all models of experimental periodontal disease induction, independent of tissue alterations. These mice models of periodontitis validates, compliments, and enhances published PD models that utilize ligature or oral gavage and supports the importance of a successful colonization of a susceptible host, a bacterial invasion into vulnerable tissue, and host-bacterial interactions that lead to tissue destruction.
  
  
  CONCLUSIONS
  The ligature model was an effective approach to induce inflammation and bone loss similar to human periodontitis, but the oral gavage models were not efficient in inducing periodontal inflammation and tissue destruction in the conditions studied. Ligature models can provide a basis for future interventional studies that contribute to the understanding of the disease pathogenesis and the complex host response to microbial challenge.
authors.affiliation: Division of Diagnostic and Surgical Sciences, UCLA School of Dentistry, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA. molon.foar@yahoo.com.br.|Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil. molon.foar@yahoo.com.br.
authors.forename: Rafael Scaf
authors.initials: RS
authors.lastname: de Molon
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Vinicius Ibiapina
authors.initials: VI
authors.lastname: Mascarenhas
authors.affiliation: Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Erica Dorigatti
authors.initials: ED
authors.lastname: de Avila
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Livia Sertori
authors.initials: LS
authors.lastname: Finoti
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Gustavo Boze
authors.initials: GB
authors.lastname: Toffoli
authors.affiliation: Department of Physiology and Pathology, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Denise Madalena Palomari
authors.initials: DM
authors.lastname: Spolidorio
authors.affiliation: Department of Morphology, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil.
authors.forename: Raquel Mantuaneli
authors.initials: RM
authors.lastname: Scarel-Caminaga
authors.affiliation: Division of Diagnostic and Surgical Sciences, UCLA School of Dentistry, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA.|Molecular Biology Institute, UCLA, Los Angeles, CA, 90095, USA.
authors.forename: Sotirios
authors.initials: S
authors.lastname: Tetradis
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University, Rua Humaita, 1680, Centro, 14801-903, Araraquara, SP, Brazil. cirelli@foar.unesp.br.|School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, Araraquara, SP, 14801-903, Brazil. cirelli@foar.unesp.br.
authors.forename: Joni Augusto
authors.initials: JA
authors.lastname: Cirelli
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology* / Q000382:microbiology; D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D016967:Fusobacterium nucleatum; D054884:Host-Pathogen Interactions; D007249:Inflammation; D008026:Ligation; D051379:Mice; D008810:Mice, Inbred C57BL; D010518:Periodontitis / Q000382:microbiology*; D016966:Porphyromonas gingivalis; D011897:Random Allocation
keywords: Fusobacterium nucleatum; Host-parasite interaction; Mice; Periodontal disease; Periodontitis; Porphyromonas gingivalis