Prophylactic Vaccination Against Periodontal Disease: A Systematic Review of Preclinical Studies

Abstract

Periodontal vaccine against periodontopathic bacteria has been tested in various animal models, such as in non-human primates and murine species. The aim of this preliminary study is to systematically review all preclinical (i.e., animal) studies that present supporting evidence for the feasibility of formulating a prophylactic human periodontal vaccine. A manual and electronic literature search was made for animal studies up to February 2010 that presented clinical, morphologic (alveolar bone level), and immunologic data for the efficacy of a prophylactic periodontal vaccine. A systematic approach was followed by two independent reviewers and included eligibility criteria for study inclusion, quality assessment, determination of outcome measures, screening method, data extraction, data synthesis, and drawing of conclusions. Only two randomized controlled animal trials qualified, and they reported exactly opposite effects of vaccine administration in Macaca fascicularis experimental periodontitis models by administration of two different agents (i.e., a negative effect with combined whole-cell antigens of Porphyromonas gingivalis and Prevotella intermedia in contrast to a positive effect with cysteine proteases of P. gingivalis). However, no statistical process could be applied to their results (data inadequately reported) in order to pool and evaluate the changes in outcome measures after vaccine administration, which, highlighted their mediocre study quality. Because of the insufficient quantity and quality of animal trials, no adequate evidence could be gathered to use the beneficial effects of these animal experiments to formulate a prophylactic human periodontal vaccine. Thus, good-quality animal trials are needed in this field of vaccine testing.