title: Prevalence of treponema species detected in endodontic infections: systematic review and meta-regression analysis.
abstract: BACKGROUND
  This systematic review and meta-regression analysis aimed to calculate a combined prevalence estimate and evaluate the prevalence of different Treponema species in primary and secondary endodontic infections, including symptomatic and asymptomatic cases.
  
  
  METHODS
  The MEDLINE/PubMed, Embase, Scielo, Web of Knowledge, and Scopus databases were searched without starting date restriction up to and including March 2014. Only reports in English were included. The selected literature was reviewed by 2 authors and classified as suitable or not to be included in this review. Lists were compared, and, in case of disagreements, decisions were made after a discussion based on inclusion and exclusion criteria. A pooled prevalence of Treponema species in endodontic infections was estimated. Additionally, a meta-regression analysis was performed.
  
  
  RESULTS
  Among the 265 articles identified in the initial search, only 51 were included in the final analysis. The studies were classified into 2 different groups according to the type of endodontic infection and whether it was an exclusively primary/secondary study (n = 36) or a primary/secondary comparison (n = 15). The pooled prevalence of Treponema species was 41.5% (95% confidence interval, 35.9-47.0). In the multivariate model of meta-regression analysis, primary endodontic infections (P < .001), acute apical abscess, symptomatic apical periodontitis (P < .001), and concomitant presence of 2 or more species (P = .028) explained the heterogeneity regarding the prevalence rates of Treponema species.
  
  
  CONCLUSIONS
  Our findings suggest that Treponema species are important pathogens involved in endodontic infections, particularly in cases of primary and acute infections.
authors: Department of Semiology and Clinics, Postgraduate Program in Dentistry, UFPel, Federal University of Pelotas, School of Dentistry, Pelotas, Rio Grande do Sul, Brazil.
authors: Fábio R M
authors: FR
authors: Leite
authors: Department of Restorative Dentistry, Postgraduate Program in Dentistry, UFPel, Federal University of Pelotas, School of Dentistry, Pelotas, Rio Grande do Sul, Brazil.
authors: Gustavo G
authors: GG
authors: Nascimento
authors: Department of Restorative Dentistry, Postgraduate Program in Dentistry, UFPel, Federal University of Pelotas, School of Dentistry, Pelotas, Rio Grande do Sul, Brazil.
authors: Flávio F
authors: FF
authors: Demarco
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas, UNICAMP, Piracicaba, São Paulo, Brazil.
authors: Brenda P F A
authors: BP
authors: Gomes
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas, UNICAMP, Piracicaba, São Paulo, Brazil; Department of Restorative Dentistry, Endodontics Division, UNESP, São Paulo State University, São José dos Campos Dental School, São José dos Campos, São Paulo, Brazil.
authors: Cesar R
authors: CR
authors: Pucci
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas, UNICAMP, Piracicaba, São Paulo, Brazil; Department of Restorative Dentistry, Endodontics Division, UNESP, São Paulo State University, São José dos Campos Dental School, São José dos Campos, São Paulo, Brazil. Electronic address: frederico.martinho@fosjc.unesp.br.
authors: Frederico C
authors: FC
authors: Martinho
mesh_terms: D003788:Dental Pulp Diseases / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D010482:Periapical Abscess / Q000453:epidemiology / Q000382:microbiology; D010485:Periapical Periodontitis / Q000453:epidemiology / Q000382:microbiology; D015995:Prevalence; D014211:Treponemal Infections / Q000453:epidemiology*
keywords: Endodontic infection; Treponema; meta-regression analysis; systematic review