Are There any Association Between Entamoeba gingivalis and Trichomonas tenax in Dental and Periodontal Diseases? A Systematic Review and Meta-analysis

There are frequent epidemiological and experimental proofs to propose that Entamoeba gingivalis and Trichomonas tenax infections are ignored factors for the development of dental and periodontal diseases. For a more comprehensive review, the present study was designed and conducted, including a systematic search in PubMed, Scopus, Web of Science, and Google Scholar databases for retrieving related reports up to December 01, 2019. Finally, 48 studies (a total of 70 datasets), including 30 datasets with case-control designs (1711 patients and 614 controls) and 40 datasets with cross-sectional designs (a total of 7257 participants) met the eligibility criteria. Based on the random-effects model, the pooled prevalence of protozoan infections in dental and periodontal patients was estimated to be 25.2% (95% CI, 21.2-29.8%; 2210/8968). In case-control designed studies, the prevalence of protozoan infections in dental and periodontal patients (35.8%, 614/1711) was found to be significantly higher than in controls (14.4%, 198/1371; OR: 4.15, 95% CI: 2.92-5.92). In addition, E. gingivalis (OR: 3.81, 95% CI: 2.36-6.14) and T. tenax (OR: 5.08, 95% CI: 2.81-9.20) were significantly higher in dental and periodontal patients compared to the controls. Our results demonstrated an apparently significant association between these protozoan infections in dental and periodontal patients. In conclusion, more standardized experimental designs are proposed using the animal model, and longitudinal (cohort) studies support the association between these protozoan infections in dental and periodontal patients to understand whether E. gingivalis and T. tenax infections are a co-factor in the development of dental and periodontal patients.